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DEPARTMENT   OF   THE    INTERIOR 


MONOGRAPHS 


United  States  Geological  Survey 


VOLUME    XXXYIII 


WASHINGTOlf 

GOVERNMENT     PRINTING     OFFICE 
1899 


Digitized  by  the  Internet  Archive 

in  2009  with  funding  from 

Boston  Library  Consortium  IVIember  Libraries 


http://www.archive.org/details/illinoisglaciallOOIeve 


UNITED  STATES  GEOLOGICAL  SURVEY 

CHARLES   D.  WALCOTT,   DIRECTOR 


THE 


ILLINOIS  GLACIAL  LOBE 


BY 


FR^NK    LEVERETT 


WASHINGTON 

GOVERNMENT  PRINTING  OFFICE 
1899 


^&^l 


CONTENTS. 


Letter  of  transmittal xv 

Abstract  of  voLUiMii xaii 

Chapter  I. — Introduction 1 

Chapter  II.— Physical  features 7 

Chapter  III. — Outline  of  time  rel.a^tioxs  or  glacial  succession 19 

Chapter  IV. — The  Illinoi an  drift  sheet  and  its  relations 24 

General  statement 24 

Relation  to  outlying  and  underlying  drift 24 

Relation  to  the  lowan  drift  sheet 24 

Culmination  of  the  Illinois  lobe  at  the  Illinoiau  stage 25 

General  aspects  of  the  Illinoiau  drift  sheet 25 

Extont  of  its  exposures 25 

Topographic  expression -  - 26 

Thickness  of  the  drift 27 

Structure  of  the  drift - --  27 

Gumbo  (?) 28 

Sections  of  the  Illinoiau  drift 33 

The  drift  border 1 -- 34 

Distribution - 34 

Topographic  expression 38 

.Structure  of  the  drift  border 40 

Character  of  the  out  wash 70 

The  i-idged  dri  ft  of  the  Kaskaskia  Basin 71 

Buffalo-  Hart  moraine 74 

Eskers  or  gravelly  rjdges  of  northwestern  Illinois 76 

Leaf  River  or  Adeline  esker - 76 

Hazelhurst  esker 78 

Garden  Plain  esker 79 

Pecatonica  esker  system - 80 

CedarviDe  belt 81 

Orangeville  belt.. 81 

General  observations - 82 

Transported  rook  ledges - 82 

Glacial  stria; - 84 

Effect  of  the  Illiuoian  ice  invasion  on  the  outer-border  drainage 89 

Temporary  displacement  of  the  Missis8ii)pi  River 89 

Changes  of  drainage  in  southwestern  Indiana , 97 

Plei-stocene  deposits  beneath  the  Illiuoian  till  sheet 105 

Kansan  till 105 

Pre-Illiuoian  till  and  associated  deposits j 107 

Silveria  ( ?)  formation  and  other  silt  deposits Ill 

Chapter  V.— The  Yarmouth  soil  and  weathered  zone 119 

Weathering  of  the  buried  Kansan  drift - 119 

Buried  soil,  peat,  etc 120 

Erosion  of  the  Kansan  drift  sjheet 121 

Organic  remains 123 

Y 


VI  CONTENTS. 

Page. 

Chaptki!  VI. — The  Sangamon  .soil  and  weathered  zone 125 

CriAPTEii  VII. — The  Iowan  driet  sheet  and  associated  deposits 131 

The  Iowan  sheet  of  the  Illinois  lobe 131 

Distribution  or  extent - 131 

Topographic  expression - 134 

Thickness  of  tlie  drift 136 

Structure  of  the  drift - 137 

StriiB 140 

Probable  extent  of  Iowan  drift  sheet  beneath  the  Wisconsin 141 

Probable  extent  of  Iowa  portion  of  Iowan  drift 144 

Relation  of  the  Illinois  and  Iowa  ice  lobes 151 

The  Iowan  loess - 153 

Distribution - 153 

Variations  in  thickness 155 

Structure - 156 

Fossils - 165 

Mode  of  deposition - 176 

Chapter  VIII. — The  Peorian  soil  and  weathered  zone  (Toronto  ior.mation?) 185 

General  statement 185 

Soil  and  peat  between  the  Iowan  and  AViscons-n  drift  sheets 185 

Leached  loess  beneath  the  Wisconsin  drift 187 

Iowan  outline  compared  with  succeeding  and  preceding  glaciations 188 

Change  in  attitude  of  the  land 188 

Length  of  the  Peorian  stage - - 188 

The  Toronto  formation  189 

Chapter  IX. — The  early  Wisconsin  drift  sheets 191 

General  statement 191 

Section  I.    Shelbyville  morainic  system 192 

Extent  of  the  Shelbyville  sheet 192 

Shelbyville  moraine 192 

Distribution 193 

Relief 194 

Range  in  altitude 194 

Surface  contours _. - 195 

Structure  and  thickness  of  drift - 197 

Character  of  out  wash 208 

Inner-border  tr.act 213 

Topography 213 

Thickness  of  drift 213 

Structure  of  d rift 213 

Cerro  Gordo  moraine 218 

Distribution 218 

Topographic  expression 218 

Structure  of  the  drift 219 

Character  of  out  wash 221 

Inner-border  tract 222 

Section  II.   Champaign  nmrainic  system 223 

Distribution 223 

Relief 225 

Range  in  altitude 226 

Surface  contours 227 

Thickness  and  structure  of  drift 231 

Character  of  outwash  237 

Associated  till  plains 239 

Section  III.    Bloomington  morainic  system 240 

Distribution 241 

Relief 244 


CONTENTS.  yjj 

Chapter  IX.— The  eai!ly  Wisconsin  drift  sheicts— Coutinued. 

Section  III.   Blooiuington  morainic  system— Continued.  ^^^' 

Ran,!>e  in  altitude ,._ 

--.  .._._.. , __  — .... -.-...__...._..  24:0 

Snrf'ace  contours _._ 

'' . .  ..  — ,  ,  —  ..  __  —  _ ^ ■i45 

Between  western  Kane  County  and  the  head  of  Bureau  Creek 246 

In  Bureau  Creek  drainage  basin 1^.^ 

In  Bureau,  Marshall,  and  Peoria  counties ""       25O 

,               Between  the  Illinois  and  Mackinaw  rivers 9-, 

Between  the  Mackinaw  River  and  Ford  County  reentrant 055 

The  reentrant  in  Ford  County 9-T 

Eastward  from  the  Ford  County  reentrant  to  western  Indiana 255 

The  ijortion  covered  hy  the  late  Wisconsin  drift 257 

The  weak  moraine  in  eastern  Iroquois  County,  Illinois 258 

Cropsey  Ridge f,_„ 

Chats worth-Cayuga  Ridge ~)sq 

Farm  Ridge  or  Grand  Ridge oro 

Thickness  of  drift 9„f, 

Structure  of  drift ZJl 

" .iDO 

Character  or  outwash „..„ 

^   ^  " 270 

Intermorainic  tracts .„„ 

Distribution  or  extent i .jo„ 

General  features '       9„„ 

Thickness  of  drift ^o^ 

Structure  of  drift : . . 900 

Kaneville  esker  and  delta 901 

Little  Rock  esker,  or  "  Devils  Backbone  " oita 

Covel  Ridge "       ^sg 

Onarga  Ridge „on 

^  °  289 

Section  IV.    The  composite  morainic  belt  of  northern  Illinois 09O 

Marengo  Ridge f,q„ 

Distribution ^\^ 

Relief .jQ^ 

Surface  contours 9q^ 

Thickness  of  drift 90, 

Structure  of  drift 9qo 

Character  of  outwash .              .  r,q. 

Inner-border  phenofiiena 9q- 

Correlations .,„_ 

Portion  of  the  composite  belt  west  of  Fox  River om 

General  features 9q_ 

Structure  of  drift onn 

Correlations 0^9 

Portion  of  the  composite  belt  cast  of  Fox  River 304 

Distribution  and  connections nn< 

General  features oj,^ 

Thickness  of  drift ." ong 

Structure  of  drift onp 

Section  V.    The  Marseilles  moraine oqj 

Distribution 007 

Range  in  altitude ong 

Relief _ o/.q 

Surface  contours oqq 

Thickness  of  drift 011 

Structure  of  drift 3j2 

Character  of  outwash gj^o 

Inner-border  til.1  plain qjg 


Vlir  CONTENTS. 

Page. 

Chapteu  X.— Thk  late  Wisconsin  nRii-r  sheets 317 

Basis  for  separat  ion  from  the  early  Wisconsin 317 

Outline  of  the  late  Wisconsin  liorder .-. 318 

Section  I.   The  Minooka  till  ridge 319 

Ilistribution 319 

Probable  line  of  continuation -- - 319 

Relief - 320 

Thickness  of  dri It , 320 

Structnre  of  drift - - 321 

Character  of  the  outwash 321 

Inner-border  till  plain 324 

Section  II.   Bowlder  belts 325 

Section  III.   Lake  Kankakee  328 

Extent  of  the  sand - 329 

Range  in  altitude  of  the  border  of  the  sand - 331 

Surface  contours - - 33- 

Thickness  of  the  sand - 333 

A'ariatious  in  coarseness - - 333 

Interpretations - 334 

Section  IV.    The  Valparaiso  morainic  system - 339 

Distribution 339 

Border  between  the  Lake  Michigan  and  Saginaw  Bay  lobes 340 

Range  in  altitude - 34.3 

Surface  contours - 345 

Detailed  description  of  the  Michigan  portion 34!^ 

Thickness  of  the  drift -- 353 

Structure  of  the  drift -  - 356 

Character  of  the  outwash   375 

Section  V.    The  lake-border  morainic  system - 380 

Till  ridges  of  Lake  and  Cook  counties,  Illinois 380 

The  outer  or  west  ridge 380 

The  middle  ridge - 381 

The  east  riilge 381 

Probable  continuations 382 

Relief 384 

Thickness  of  drift : 384 

Structure  of  drift 38.i 

Till  ridges  on  the  southeast  border  of  Lake  Michigan 386 

Tho  outer  ridge  - --■  386 

Covert  Ridge 388 

Zeeland  Ridge 390 

Relief 391 

Range  in  altitude 391 

Thickness  of  drift 39- 

Structurc  of  drift 393 

Character  of  the  outwash ; 403 

Associated  till  plains 404 

Altitude  and  slopes 4"* 

Thickness  of  drift ■106 

Structure  of  drift -107 

Section  VI.   Stria'  within  limits  of  Shelbyville  moraine 412 

Chapter  XI. — The  Chicago  Outlet  and  iieaches  op  Lake  Ciucaoo 418 

Previous  writers 418 

The  Chicago  Outlet *20 

The  glacial  T^ake  Chicago 427 

Upper,  or  Glcu wood,  beach 428 


CONTENTS.  IX 

Chapter  XI. — The  Chicago  Outlet  and  beaches  of  Lake  Chicago— Continued.  Pao-e. 

The  glacial  Lake  Chicago — Continuefl. 

Interval  of  emergence _ 440 

Second,  or  Calumet,  beach __ 443 

Possible  second  emergence 44g 

Third,  or  Tolleston,  beach 447 

The  preseut  beach  of  Lake  Michigan _ 453 

CHArTEi;  XII. — Influence  of  the  drift  on  drainage  system.s  and  drainage  conditions..  460 

The  Mississippi  Valley 461 

Accession  from  the  north  (?) 461 

Minor  deflection  at  Fultou,  Illinois 462 

Deflection  past  the  Leclaire,  or  upper,  rapids 463 

Reestablished  stream  between  upper  and  lower  rapids _ .  _ 467 

Deflection  at  the  lower  rapids ' 469 

Reestablished  stream  below  the  lower  rapids 473 

Deflections  south  of  glacial  lioundary 474 

Rock  floor  and  present  stream  compared 474 

Minor  tributaries  of  the  Mississipppi _. 477 

Apple  River 477 

Plum  River 478 

Edwards  River 478 

Henderson  River _ 479 

Flint  River 479 

Lost  Creek 480 

Bear  Creek 480 

Bay  Creek 480 

Big  Meadow  channel 481 

Rock  River  drainage  basin 483 

The  preglacial  drainage 483 

Present  cour.se  of  Rouk  River 486 

Greeu  River 492 

Rock  gorges  of  northwestern  Illinois 493 

Illinois  River  drainage  basin. 496 

The  lower  Illiuois 1 499 

The  upper  Illinois 501 

Des  Plaines  River 503 

Kankakee  River 505 

Au  Sable  Creek  and  Nettle  Creek 508 

Mazon  Creek,  etc 508 

Fox  River 509 

Covel  Creek 510 

Vermilion  River _ 511 

Little  Vermilion  River,  etc 512 

Bur.eau  Creek 512 

Kickapoo  Creek 513 

Farm  Creek 514 

Mackiuaw  River 514 

Quiver  Creek 515 

Copperas  Creek 516 

Spoon  River 516 

Sangamon  River 517 

Crooked  Creek 520 

McKee's  Creek 521 

Indian,  Mauvaise  Terre,  and  Big  Sandy  creeks 521 

Apple  Creek.. .' 522 

Macoupin  Creek 522 

Otter  Creek ^ 523 


X  CONTENTS. 

Chapter  XII. — Inkluexce  of  the  drift  on  urainage  systems  and  conditions— Cont'd.  Va.g:e. 

Kaskaslcia  River  drainage  basin 523 

Kaskaskia  River 523 

Shoal  Creek 524 

Silver  Creek - 525 

Big  Muddy  River  drainage  basin 526 

Saline  River  drainage  basin 527 

Cache  River -  -  - 528 

Wabash  River  drainage  basin - - 528 

Preglacial  Wabash  \' alley - 529 

Minor  deflections  of  the  Wabash 530 

Little  Wabash  River -- - 530 

Bon  Pas  River 531 

Patoka  River -- - 532 

White  River - 532 

Embarras  River - - 534 

Busseron  Creek - - 535 

Big  Raccoon  Creek - 535 

Sugar  Creek 536 

Vermilion  River 536 

Lake  Michigan  drainage  basin - 538 

Chicago  River - 538 

Calumet  River - -- 538 

Trail  Creek - 539 

Galien  River --- 539 

St.  Joseph  River 539 

Pawpaw  River - -  540 

Black  River -- --- 541 

Kalamazoo  River - 541 

Chapter  XIII. —Average  thickness  of  the  drift  in  Illinois 542 

Chapter  XIV. — Wells  of  Illinois 550 

Introduction .  - - _- - 550 

Classification  of  underground  waters 550 

The  geologic  formations 552 

Attitude  of  the  strata 553 

Essential  conditions  for  artesian  wells 555 

Relation  of  the  drift  to  ordinary  wells 557 

Gas  wells --- 557 

Tabulation  of  sources  for  city  water  supply 557 

Detailed  discussion 564 

Jo  Daviess  County 564 

Stephenson  County 567 

Winnebago  County 569 

Boone  County 573 

McHcnry  County 575 

Lake  County 579 

Cook  County 581 

Dupage  County -'91 

Kane  County 594 

Dekalb  County 599 

Ogle  County 604 

Lee  County 608 

Carroll  County 611 

Whiti^sido  County 614 

Rock  Island  County 619 

Mercer  County 622 

Henry  County 623 


CONTENTS.  XI 

Chapter  XIV. — Wells  of  Illinois — Continued.  Page. 

Detailed  discussion — Continued. 

Bureau  County.. - .- 626 

Pntnam  County - - 633 

Lasalle  County -  — — 635 

Kendall  County - 643 

Grundy  County - - --- 645 

Will  County - 648 

Kankakee  County - - 653 

Iroquois  County — -- -- 654 

Ford  County - 662 

liivingston  County - 664 

Marshall  County - -  - -  -  -  668 

Woodford  County - - 670 

Stark  County - 672 

Peoria  County 673 

Knox  County - - 676 

Warren  County - 678 

Henderson  County ' ---  679 

Hancock  County - - - 681 

McDonough.  Couuty - 685 

Fulton  County --  686 

Mason  County - 688 

Tazewell  County 689 

McLean  County .  - - 692 

Vermilion  County -- 697 

Champaign  County - 701 

Piatt  Couuty 703 

Dewitt  County - 704 

Logan  County 707 

Menard  County - - 709 

Cass  County ' - 710 

Schuyler  County - 711 

Brown  County 712 

Adams  County 713 

Pike  County  . .  - 718 

Scott  County - 721 

Morgan  County - - 722 

Sangamon  County 724 

Christian  County 725 

Macon  County — 727 

Moultrie  County - 729 

Douglas  County 731 

Edgar  County 732 

Clark  Couuty 733 

Coles  Couuty   734 

Cumberland  County 736 

Shelby  County 737 

Montgomery  County 740 

Macoupin  County 742 

Greene  County 744 

Calhoun  County - 745 

Jersey  County - - 746 

Madison  County 748 

Bond  County --- 750 

Fayette  County - 752 


XII  CONTENTS. 

Chapter  XIV. — Wells  of  Illinols — Contiuueil.  Page. 

Detailed  discussion — Continued. 

Effingham  County ''53 

Jasper  County ''^54 

Crawford  County - 755 

Lawrence  County 756 

Richland  County 756 

Clay  County - - 757 

Marion  County 758 

Clinton  County - 760 

St.  Clair  County - 761 

Monroe  County 765 

Randolph  County 767 

AVashingtdu  County 770 

Perry  County - 771 

Jeft'erson  County - 773 

AVayne  County 774 

Edwards  and  Wabash  counties 775 

White  County 776 

Hamilton  County 777 

Franklin  County - 778 

Jackson  County 778 

Williamson  County - 780 

Saline  County 781 

Gallatin  County 783 

Unglaciated  counties  of  southern  Illinois 784 

CiiAPTEH  XV.— Soils 788 

Sources  of  soil  material 788  ' 

Classes  of  .soil - 788 

Residuary  soils.. 791 

Bowlder-clay  soils 792 

Gravelly  soils 792 

Sandy  soils 793 

Bluff-loess  soils 793 

Silts  slowly  pervious  to  water 794 

Fine  silts,  nearly  impervious - 795 

Peaty  and  organic  soils 796 

Index - - 799 


ILLUSTRATIONS, 


Page. 
Plate  I    Map  showing  the  several  drift  sheets  and  the  present  glaciation  of  North  America .  2 

II.  Map  showing-  base  lines  and  principal  meridians  in  the  district  covered  by  the 

Illinois  glacial  lobe -.; 

III.  Topographic  map  of  Illinois  and  western  Indiana ^ 

IV    Map  showing  areas  between  100-foot  contours * 

V.  Profiles  across  Lake  Michigan .- " 

VI.  Glacial  map  of  Illinois  ice  lobe - 

VII.  Bowlder  bed  at  Keokuk,  Iowa J^ 

VIII.  Glacial  map  of  southwestern  Indiana - - 

IX    Glacial  map  of  south-central  Indiana J^ 

X    A   Sano-amon  soil,  near  view;  i?,  Sangamon  soil,  more  distant  view 1-b 

XT.  A,  Exposure  on  Farm  Creek,  near  Peoria;  IS,  exposure  on  railroad  cutting  east 

of  Peoria " 

XII.  Glacial  map  of  northwestern  Illinois 

XIII.  Exposure  of  Wisconsin  gravel -j' 

XIV.  Glacial  map  of  parts  of  Kane  and  Kendall  counties,  Illinois -JH 

XV.  Glacialmap  of  southwestern  Michigan 340 

■XVI.  Striation  of  under  surface  of  limestone '^1° 

XVII.  Map  of  Lake  Chicago  area .'.':"" 

XVIII.  Topographic  map  showing  drainage  features  near  Fulton,  Illinois,  and  lu  vicinity 

of  the  upiier  rapids  of  the  Mississippi. ; In  pocket. 

XIX.  Topographic  map  showing  drainage  features  near  Ottawa,  Illinois 508 

XX.  Map  of  Illinois,  showing  distribution  of  wells - - - ^J^^ 

XXI    Geoloo-ic  map  of  Illinois  and  western  Indiana ^o- 

XXIL  Map  showing  main  absorbing  areas  for  the  Potsdam  and  St.  Peters  formations  --  .5.56 

Xx'lII.  Map  showing  distribution  of  artesian  wells  and  deep  borings  5o6 

VxiV.  Map  showing  the  relation  of  the  drift  to  ordinary  wells 556 

Fig.  1.   Section  of  Silveria  formation  near  Freeport,  Illinois 112 

2.  Glaciated  surface  in  bed  of  Chicago  drainage  canal *1d 

3    Grooves  exposed  in  bed  of  Chicago  drainage  canal 11^ 

4.  Sketch  map  of  the  region  bordering  the  lower  rai^ids  of  the  Mississippi  River 468 

0.   Section  from  Sonora,  Illinois,  toArgyle,  Iowa - *69 

6    Sections  across  Rock  River  Valley,  in  northern  Illinois 

7.  Section  from  the  Wisconsin  River,  in  Grant  County,  Wisconsin,  southward  to  Cap  au 

Gres,  near  the  mouth  of  the  Illinois •       °i^ 

8.  Section  from  Galena  to  Olney,  Illinois - - ^^^ 

9.  Section  from  Davenport,  Iowa,  to  Joliet,  Illinois ='=' 

XIII 


LETTER  OF  TRANSMITTAL. 


University  of  Chicago,  July  15^  1898. 

Sir:  I  have  the  honor  to  transmit  herewith  the  manuscript  of  a  mono- 
g-raph  on  The  lUinois  Grlacial  Lobe,  by  Mr.  Frank  Leverett.  This  is  one 
of  a  series  of  monographs  which  are  in  course  of  preparation  on  the  glacial 
formations  of  the  Northern  States.  My  instructions  when  entering  upon 
the  work  of  the  Geological  Survey  were  to  prepare  a  monograph  on  the 
terminal  moraines  which  stretch  from  Dakota  to  the  Atlantic.  Soon  after 
the  inauguration  of  the  work,  however,  it  became  ajjparent  that  the  mo- 
rainic  systems  were  more  amply  and  more  intricately  developed  than  had 
been  at  first  apprehended,  and  that  they,  together  with  the  associated  glacial 
formations,  were  so  highly  diversified  and  so  complicated  that  their  eluci- 
dation could  be  reached  only  by  prolonged  investigation  involving  detailed 
work.  It  was  therefore  thought  best  to  study  the  glaciated  area  by  sec- 
tions, and  to  publish  the  results  of  these  partial  studies  as  they  might  be 
ready,  reserving  for  a  later  date  the  monographic  treatment  of  the  whole. 
Early  in  the  preliminary  work  special  attention  was  drawn  to  the  Illinois 
glacial  lobe,  because  its  morainic  ridges  and  its  till  sheets  were  very  widely 
deployed  and  because  its  relations  were  such  as  to  make  it,  in  some  sense,  a 
key  to  the  whole  glacial  series  east  of  the  Mississippi;  and  hence  it  has  been 
given  precedence. 

Previous  to  my  connection  with  the  Geological  Survey  I  had  made 
sufficient  reconnaissance  of  the  area  covered  by  this  monograph  to  deter- 
mine some  of  its  salient  features,  and  at  tlie  same  time  to  disclose  many 
other  features  which  only  patient  and  detailed  study  could  elucidate.  The 
results  of  these  partial  studies,  combined  with  observations  made  during  the 
first  year  of  my  connection  with  the  Survey,  were  embraced  in  a  prelim- 
inary paper  published  in  the  Third  Annual  Report.  The  more  detailed 
work  was  taken  up  by  Prof.  R.  D.  Sahsbury,  Prof.  L.  C.  Wooster,  Mr.  Frank 


XVI  LETTER  OF  TRANSMITTAL. 

Leverett,  iiiid  lUAxolt'  (•(injointh"  in  188G.  Later  the  whole  work  was 
coniiuitted  to  Mr.  Leverett,  with  tlie  gratify ing  results  of  which  this  mon- 
ogi'aj)li  is  au  expression.  Tlie  relations  of  Mr.  Leverett  and  myself  during- 
the  progress  of  the  investigation  have  been  unusually  intimate,  and  it  has 
been  a  pleasure  to  contribute  to  the  work  such  data  and  suggestions  as  m^- 
studies  in  this  and  other  regions  permitted.  I  trast  that  the  monogi-aph  will 
jjrove  a  valuable  contribution  to  the  complex  problem  presented  by  the  gla- 
cial series  of  the  Northern  United  States. 

Very  respectfully,  yours,  T.  C  Chamberlin, 

Geologist  in  charge. 
Hon.  Charles  D.  Walcott, 

Director  United  States  Qeological  Survey. 


ABSTRACT   OF   TOLUME. 


Chapter  I.  Introduction. — The  Illinois  glacial  lobe  formed  tlie  southwestern 
part  of  the  great  ice  field  that  extended  from  the  high  lands  east  and  south  of  Hudson 
Bay  southwestward  over  the  basins  of  the  Great  Lakes  and  the  north-central  States 
as  far  as  the  Mississippi  Valley.  It  overlapped  a  previously  glaciated  region  on  the 
southwest,  whose  drift  was  derived  from  an  ice  field  that  moved  southward  from  the 
central  portion  of  the  Dominion  of  Canada  as  far  as  the  vicinity  of  the  Missouri  Eiver. 
This  southwestern  part  of  the  eastern  ice  field,  being  mainly  within  the  limits  of  the 
State  of  Illinois,  has  received  the  name  Illinois  Glacial  Lobe. 

The  results  of  earlier  studies  by  Chamberlin,  Salisbury,  and  others  are  noted, 
and  the  plan  of  investigation  is  set  forth.  A  brief  explanation  of  the  method  of  num- 
bering townships  is  presented. 

Chapter  II.  Physical  features. — -The  variations  in  altitude  are  set  forth  in 
a  topographic  map  and  also  in  tables,  and  the  marked  increase  in  altitude  of  certain 
parts  of  the  region  because  of  drift  accumulations  is  considered.  The  consxaicuous 
reliefs  of  the  rock  surface  are  briefly  touched  upon,  and  the  preglacial  valleys  receive 
passing  notice.  Profiles  and  maps  are  extended  across  the  bed  of  Lake  Michigan  as 
well  as  border  districts,  and  the  inequalities  of  the  lake  basin  are  briefly  discussed. 

Chapter  III.  Outline  of  time  relations  or  glacial  succession. — A 
sketch  of  the  major  and  minor  divisions  of  the  drift  sheets  and  of  the  intervals 
between  them  is  accompanied  by  a  brief  explanation  of  the  basis  for  the  classification 
adopted. 

Chapter  IV.  The  Illinoian  drift  sheet  and  its  relations. — The  Illinoian 
is  the  most  extensive  drift  sheet  formed  by  the  Illinois  glacial  lobe  and  receives  its 
name  because  of  its  wide  exposure  in  the  State  of  Illinois.  The  evidence  that  the 
Illinoian  drift  sheet  should  be  separated  from  the  outlying  and  underlying  drift  and 
also  from  the  lowan  drift  is  briefly  set  forth.  The  aspects  of  the  Illinoian  drift  sheet 
are  then  discussed,  its  topography  as  well  as  its  structure  being  considered.  In 
connection  with  this  drift  sheet  a  very  adhesive  clay,  known  as  "gumbo,"  which 
caps  it,  is  described  and  the  questions  of  its  relation  to  this  drift  sheet  and  to  the 
overlying  loess  are  considered.  A  detailed  descrii^tion  of  the  border  of  the  Illinoian 
MON  xxxviii 2  ^"^'ii 


XN'JU  ABSTRACT  OP  VOLUME. 

drift  sheet  is  then  given,  wbicli  is  followed  by  a  description  of  the  moraines  and 
other  drift  aggregations  back  from  the  border. 

Remarkable  instances  of  the  transportation  of  rock  ledges  are  noted.  The  strife 
pertaining  to  this  invasion  are  discussed  iu  some  detail.  The  effect  of  this  ice 
invasion  and  its  drift  deposits  upon  the  outer-border  drainage  is  touched  upon,  but 
the  detailed  discussion  of  the  influence  of  the  drift  upon  drainage  is  deferred  to  a 
later  chapter.  The  chapter  closes  with  a  discussion  of  the  deposits  which  underlie 
the  Illinoian  drift  sheet. 

Chapter  V.  The  Yarmouth  soil  and  weathered  zone. — A  well-defined 
soil  and  weathered  zone  which  appear  between  the  Kansan  and  Illiuoian  drift  sheets 
in  the  overlap  of  the  latter  upon  the  former  are  described,  and  sections  are  presented 
which  show  clearly  the  relations  to  these  drift  sheets.  The  amount  of  erosion  effected 
during  the  interglacial  stage  is  also  considered.  The  name  Yarmouth  is  taken  from 
a  village  iu  southeastern  Iowa,  where  the  interglacial  features  were  first  recognized 
by  the  writer. 

Chapter  VI.  The  Sangamon  soil  and  weathered  zone. — Another  well- 
defined  soil  iind  accompanying  weathered  zone  which  appear  between  the  Illinoian 
drift  and  the  overlying  loess  are  described.  The  name  Sangamon  is  applied  because 
these  features  are  exceptionally  well  developed  in  the  Sangamoa  River  Basin  in  Illi- 
nois and  were  there  first  noted  by  Worthen  in  the  early  reports  of  the  Illinois  geological 
survey. 

Chapter  VII.  The  Iowan  drift  sheet  and  associated  deposits. — The 
name  Iowan  was  applied  by  Chamberlin  to  a  sheet  which  is  well  displayed  iu  eastern 
Iowa  and  which  had  beeu  brought  to  notice  by  McGee.  The  chapter  opens  with  the 
discussion  of  a  drift  sheet  of  a  similar  age  which  was  formed  by  the  Illinois  lobe,  its 
extent,  topographic  expression,  and  structure  being  considered.  The  relation  of  this 
ice  lobe  to  the  Iowa  ice  lobe,  and  the  relation  of  each  to  the  great  loess  deposit  of  the 
Mississippi  Basin  are  then  considered,  after  which  the  loess  is  discussed.  The  problem 
of  the  mode  of  deposition  of  the  loess  forms  the  closing  topic 

Chapter  VIII.  The  Peorian  soil  and  weathered  zone  (Toronto  forma- 
tion?).— The  name  Toronto  formation,  suggested  by  Chamberlin,  for  interglacial 
deposits  exposed  in  the  vicinity  of  Toronto,  Canada,  may  prove  to  be  applicable  to  a 
soil  and  weathered  zone  wliich  appear  between  the  Iowan  drift  sheet  or  its  associated 
loess  and  the  Shelbyville  or  earliest  Wisconsin  drift  sheet  which  overlies  the  Iowan. 
Exceptionally  good  exposures  of  a  soil  and  weathered  zone  at  this  horizon  in  the 
vicinity  of  Peoria,  Illinois,  make  it  seem  advisable  to  apply  the  name  Peorian,  while 
tlie  relations  of  the  Toronto  formation  renuiiii  uncertain.  Other  exposures  as  well  as 
those  near  Peoria  arc  discussed.  A  marked  interglacial  interval  between  the  Iowan 
and  Wisconsin  stages  of  glaciation  may  also  be  inferred  by  a  comparison  of  the  out- 
line of  the  ice  sheet  at  the  Iowan  stage  of  glaciation  with  that  of  the  outline  at  the 


ABSTRACT  OF  VOLUME.  xiX 

culmination  of  the  Wisconsin  stage.  It  may  also  be  inferred  by  a  change  in  the  atti- 
tude of  the  laud,  by  -which  better  drainage  conditions  were  prevalent  in  the  Wisconsin 
than  in  the  lowan  stage. 

Chapter  IX.  The  early  Wisconsin  drift  sheets.— The  Wisconsin  drift, 
named  by  Chamberlin  from  the  State  in  which  it  was  first  recognized  as  a  distinct 
drift,  is  cbaiacterized  by  large  morainic  ridges  and  comparatively  smooth  intervening 
till  plains  which  have  been  thrown  into  two  groups,  known  as  the  early  Wisconsin 
and  late  Wisconsin.  In  the  first  group  the  moraines  form  a  rudely  concentric  series, 
which  are  well  displayed  in  the  northeastern  part  of  Illinois,  but  are  largely  over- 
ridden by  the  moraines  and  drift  sheets  of  the  later  group  in  districts  farther  east. 
The  outer  border  of  the  second,  or  late,  Wisconsin  group  is  so  discordant  with  the 
moraines  of  the  first  group  that  there  seems  in  this  feature  alone  sufficient  reason  for 
separation. 

The  several  morainic  systems  of  the  early  Wisconsin  group  are  taken  up  in  suc- 
cession from  earlier  to  later,  the  distribution,  relief,  range  in  altitude,  surface  contours 
thickness  and  structure  of  the  drift,  and  the  character  of  the  outwash  being  con- 
sidered. In  connection  with  each  morainic  system  the  associated  till  plains  are 
discussed,  attention  being  given  to  the  surface  features  and  to  the  structure  and 
thickness  of  the  drift.  In  northern  Illinois  the  several  morainic  systems  are  merged 
into  a  composite  belt  so  complex  that  it  is  difficult  to  trace  the  individual  members 
The  several  moraines  and  their  associated  sheets  of  till  do  not  appear  to  be 
separated  by  intervals  so  wide  as  are  found  betweeu  the  Illinoian  and  lowan  or  the 
lowan  and  Wisconsin  drift  sheets.  Indeed,  instances  of  the  occurrence  of  a  soil  or  a 
weathered  zone  between  Wisconsin  sheets  are  very  rare.  There  may,  however  have 
been  considerable  oscillation  of  the  ice  margin. 

Chapter  X.  The  late  Wisconsin  drift  sheets.— The  basis  for  separation 
from  the  early  Wisconsin  is  first  considered,  after  which  the  several  morainic  systems 
and  their  associated  till  plains  are  taken  up  in  order  as  in  the  discussion  of  the  early 
Wisconsin  drift.  An  interpretatiou  of  the  Kankakee  sand  area  is  attempted,  though 
several  qnestions  connected  with  it  still  remain  open.  The  chapter  closes  with  a 
discussion  of  the  striae  found  within  the  limits  both  of  the  early  and  of  the  late  Wis- 
consin drift. 

Chapter  XI.  The  Chicago  Outlet  and  beaches  of  Lake  Chicago.— That 
a  body  of  water  once  extended  over  the  low  districts  bordering  the  southern  end  of 
Lake  Michigan  and  discharged  southwestward  to  the  Des  Plaines  and  thence  into 
the  Illinois  River  has  been  recognized  since  the  early  days  of  settlement,  and  several 
papers  discussing  the  beaches  and  tlie  outlet  have  appeared.  The  latter  has  long 
been  known  as  the  Chicago  Outlet,  because  it  led  away  from  the  site  of  that  city. 
The  lake  has  recently  been  given  a  name  in  harmony  with  that  of  the  outlet  (Lake 
Chicago.) 


XX  ABSTKACT  OF  VOLUME. 

After  reviewing  tbe  previous  reports  and  papers,  the  Cbicago  Outlet  is  described 
in  some  detail.  The  several  beacbes  of  Lake  Cbicago  are  tbeu  taken  up  in  order  from 
highest  to  lowest.  Tbe  chapter  ends  with  a  discussion  of  the  present  beach  of  Lake 
Michigan. 

Ghaptek  XII.  Influence  of  the  drift  on  drainage  systems  and  drain- 
age CONDITIONS. — It  is  shown  that  many  drainage  systems  are  entirely  independent 
of  the  preglacial  lines,  while  others  are  independent  only  in  part,  a  considerable  part 
of  their  courses  being  along  the  lines  of  old  valleys.  The  development  of  drainage 
systems  is  shown  to  be  much  farther  advanced  on  the  lowan  and  Illinoian  drift  sheets 
than  on  the  Wisconsin.  This  is  found  to  be  due  to  differences  in  age  and  not  to 
natural  advantages  for  discharge.  The  Wisconsin  is,  on  the  whole,  more  favored  by 
uneven  surface  for  the  rapid  development  of  drainage  lines  than  the  Illinoian.  The 
several  drainage  systems  are  discussed  in  considerable  detail. 

Chapter  XIII.  Average  thickness  of  the  drift  in  Illinois. — Illinois 
affords  an  especially  good  opportunity  for  the  estimate  of  the  thickness  of  the  drift, 
because  of  the  large  number  of  well  sections  obtained,  and  because  of  the  compara- 
tive smoothness  of  the  region.  The  inequalities  of  the  rock  surface  beneath  drift 
plains  may  be  estimated  by  the  study  of  neighboring  driftless  tracts,  as  well  as  by 
borings  and  outcrops  within  the  drift  covered  area.  There  arc  thus  two  quite  differ- 
ent methods  by  which  the  average  thickness  of  the  drift  may  be  ascertained. 

The  first  method  here  used  is  that  of  averaging  the  results  of  borings  and  out- 
crops. These  are  averaged  in  each  township  in  which  the  distance  to  rock  is  known, 
and  the  results  are  then  combined  for  the  average  of  all  the  explored  townships.  Con- 
sideration is  then  given  to  the  distribution  of  the  explored  townships  in  reference  to 
drift  plains  and  moraines  and  to  preglacial  uplands  and  valleys,  and  necessary  cor- 
rections are  made.  By  this  method  the  thickness  of  the  drift  is  found  to  bo  not  less 
than  100  feet,  and  it  may  be  1'20  feet  or  even  more. 

The  second  method,  based  upon  a  comparison  of  the  Illinois  drift  area  with  the 
neighboring  driftless  tracts,  gives  129.3  feet  as  the  average  thickness,  or  slightly  more 
than  the  highest  results  obtained  by  the  first  method.  Combining  the  two  methods, 
tbe  average  thickness  of  the  drift  of  Illinois  can  be  i^laced  at  not  more  than  130  feet 
and  not  less  than  100  feet. 

An  attempt  is  made  to  estimate  the  part  contributed  by  each  ice  invasion,  but 
the  data  prove  to  be  scarcely  complete  enough  for  a  good  estimate.  It  is  found  that 
the  general  thickness  withiu  the  limits  of  the  Wisconsin  drift  is  40  to  45  feet  greater 
than  in  the  portion  of  the  State  outside. 

Chapter  XIV.  The  wells  of  Illinois. — This  chapter  aims  to  present  all 
the  reliable  well  records  obtained  within  the  State  which  throw  light  upon  the 
deposits  jDenetrated  as  well  as  upon  the  character  of  the  water  sui)plies.  In  addition 
to  the  wells  which  terminate  in  the  drift  there  are  included  many  which  extend 


ABSTRACT  OF  VOLUME.  XXI 

deeply  into  the  underlying  rock  formations.  This  necessitates  a  classification  of  the 
underground  waters  and  a  description  of  the  several  rock  formations  penetrated, 
including  a  discussion  of  the  attitude  of  the  strata.  The  essential  conditions  for 
obtaining  artesian  wells  are  considered,  and  also  the  relation  of  the  drift  to  the 
ordinary  wells.  There  is  a  brief  discussion  of  gas  wells,  confined  mainly  to  those 
obtained  in  the  drift.  A  tabulation  of  sources  for  city  water  supply  is  then  presented, 
after  which  there  appears  a  detailed  discussion  of  wells,  taken  up  by  counties. 

Chapter  XV.  Soils. — The  sources  of  soil  material  are  first  discussed.  An 
attempt  is  then  made  to  classify  the  soils  according  to  their  origin.  Eight  classes  are 
recognized,  as  follows:  Residuary  soils,  bowlder-clay  soils,  gravelly  soils,  sandy  soils, 
bluff-loess  soils,  silts  slowly  pervious  to  water,  fine  silts  nearly  imj)ervious,  peaty  or 
organic  soils. 


THE  ILLINOIS  GLACIAL  LOBE. 


By  Frank  Levebett. 


CHAPTER   I. 

INTRODUCTION. 

The  Illinois  glacial  lobe  includes  a  portion  of  the  great  ice  sheet  which 
extended  from  the  highlands  east  and  south  of  Hudson  Bay,  southwestward 
across  Michigan,  the  Lake  Michigan  basin,  and  Illinois,  to  the  axis  of  the 
Mississippi  Valley  in  southwestern  Illinois  and  southeastern  Iowa  (PL  I). 
It  finds  its  natural  limits  on  the  northwest  at  the  border  of  the  Driftless 
Area  of  southern  Wisconsin  and  northwestern  Illinois.  On  the  west  it 
overlaps  a  region  previously  glaciated,  but  its  extent  there  is  readily  deter- 
mined, for  it  has  usually  a  definite  border  in  a  belt  of  ridged  drift.  On  the 
south  and  southeast  it  extends  to  the  unglaciated  tracts  of  southern  Illinois 
and  southern  Indiana.  From  central  Indiana  northward  it  seems  to  have 
been  merged  with  the  eastern  portion  of  the  great  ice  sheet,  except  in 
shrunken  stages.  In  the  last  stage  here  considered  it  extended  but  little 
beyond  the  borders  of  Lake  Michigan  and  was  then  distinct  fi-om  lobes  to 
the  east  lying  in  the  Saginaw  and  Maumee  basins.  The  present  report 
discusses  the  deposits  made  by  the  lobe  south  from  the  latitude  of  the 
Illinois- Wisconsin  line,  in  Illinois,  Indiana,  and  Michigan. 

The  drift  deposited  by  this  ice  lobe  has  received  considerable  attention 
from  the  geologists  of  the  several  State  surveys,  and  also  from  several 
students  of  geology  not  connected  with  official  surveys.  The  early  publi- 
cations furnish  numerous  sections  of  the  drift,  of  which  mention  is  made 
below,  which  throw  light  on  its  structure  and  thickness.     They  contain 

MON  xxxvni 1  1 


2  THE  ILLI>fOIS  GLACIAL  LOBE. 

only  occasional  references  to  the  topography  of  the  drift  surface.  Appar- 
ently the  first  clear  recognition  of  the  import  of  morainic  belts  in  this 
region  was  that  by  Prof.  T.  C.  Chamberlin,  who  began  his  investigations 
in  the  Wisconsin  Survey  in  1873,  and  who  in  1876  presented  a  map, 
before  the  Wisconsin  Academy  of  Sciences,  showing  the  distribution  of  the 
moraines  of  eastern  Wisconsin.  This  was  followed  by  one  in  1878  show- 
ing moraines  then  recognized  in  the  United  States.^  It  soon  became 
apparent  to  Professor  Chamberlin  that  sheets  of  drift  of  widely  different 
age  occur,  the  later  of  which  are  characterized  by  stronger  morainic  lines 
than  the  earlier. 

Prior  to  liie  recognition  of  the  morainic  belts  and  of  drift  sheets  of 
widely  different  ages  the  published  sections  of  the  drift  presented  many 
puzzling  features.  But  with  this  recognition  the  sections  published  by  the 
early  students  became  of  service  in  making  interpretations.  The  later 
students  are  thus  able  to  build  upon  the  work  of  the  earlier.  The  disad- 
vantages imder  which  the  earlier  students  worked,  on  account  of  the  less 
complete  knowledge  of  the  glacial  features,  can  scarcely  be  appreciated  by 
those  who  are  furnished  with  the  present  facilities  for  study.  Any  en-oneous 
interpretations  resulting  from  the  restricted  acquaintance  with  such  featm-es 
merit  a  most  charitable  construction.  For  example,  the  writings  of  Profes- 
sor Worthen  of  the  Illinois  survey  are  full  of  the  hypothesis  of  deposition 
of  the  di-ift  by  icebergs.  The  early  reports  of  the  geologists  of  the 
Indiana  survey  contain  a  similar  inteipretation  of  the  drift.  In  the  light  of 
present  knowledge  of  the  moraines,  with  their  attendant  valley  trains  of 
gravel  and  other  features  demonstrating  the  presence  of  land  ice,  the  iceberg 
hj'iDOthesis  must  of  course  be  set  aside,  but  this  study  of  moraines  has 
largely  taken  place  during  the  fifteen  or  twenty  years  since  the  reports 
refeiTed  to  were  published. 

The  present  report  is  an  outgrowth  of  studies  entered  upon  by  Pro- 
fessor Chamberlin  prior  to  the  publication  of  his  paper  in  the  Third  Annual 
Report  of  this  Survey.^  In  that  paper  it  is  shown  that  the  State  of  Illinois 
is  traversed  by  several  morainic  lines  lying  outside  the  great  moraine  which 
is  the  theme  of  the  paper.     These  lines,  together  with  others  not  then 


'  Trans.  Wisconsin  Acad.  Sci.,  Vol.  IV  (for  1876-77),  1878,  pp.  202-234;  with  two  maps. 
-Preliminary  paper  on  tho  terminal  moraine  of  the  second  Olaci.al  epoch,  by  Thomas  C.  Cham- 
li.-iliii :    Third  Ann.  Rept.  U.  S.  Geol.  Survey  (for  1881-82),  1883,  pp.  291-402. 


U.  S.  GEOLOGICAL   SURVEY. 


MONOGRAPH    XXXVIII  PL. 


157° 


137°  117° 


.-1 


'^C  E 


r-.T-'     LoivgiLiidc  37"  \Wst    Crniii  i^vemwich 


'   ^-^<i^>^. 


■t(j/;'-iJ(CiayS^-~~ji-i- 


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B  A  ' 


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} 


^  A)     ^ — - 


A.VW- 


'7^ 


lOo 


Kansan  drift 

Dlinoian  drift  i 

lowan  di-lfl  V^ 

■Wisconsinandlala-drifistieets    v^x 

Existing  glaciers  and  ice  sheets 

Quaternarj' lakes (Boraieville.Lahontan  and  Glacial  LakeA^assiz) 


\  \\   I  Glacial  currents  known  by  strias 

Glacial  currents  known  by  drift  transportation  or  otherwise  inferred_ 


30° LoTtgilu.cle  "West  20°  ft:om"Waslun.fetorL 


JULIUS  BIEN  a  CO.  LITH    N.Y, 


MAP  OF  THE  GLACIATED  AREA  OF  NORTH  AMERICA. 
(Modified  from  Upham's  map  Plate  X\t;  MonographXXV) 


BY  FRANK  LE^^RE  T  T 

1898 

Scale,  about  .5.50  miles  Lo  an  incli 


INTRODUCTION.  3 

known,  have  been  mapped  in  detail  and  a  large  amount  of  data  concerning 
them  have  been  collected. 

The  detailed  studies  were  begun  in  the  spring  of  1886,  and  the  follow- 
ing statement  concerning  them  was  made  bj  Professor  Chamberlin  in  his 
report  to  the  Director  for  the  fiscal  year  1886-87: 

Messrs.  L.  C.  Wooster,  R.  D.  Salisbury,  F.  Leverett,  and  myself  have  under- 
taken a  work  that  is  measurably  new,  though  a  part  of  the  general  plan  of  work 
previously  inaugurated.  In  the  region  about  the  head  of  Lake  Michigan  and  between 
it  and  the  Erie  basin  is  a  tract  which  was  invaded  by  successive  glacial  movements 
from  both  these  great  basins,  these  movements  being  more  or  less  inharmonious  and 
couflicting,  resulting  in  exceptionally  complicated  phenomena.  There  arose  from  this 
a  need  for  detailed  study  and  the  development  of  more  refined  methods  of  investiga- 
tion than  those  demanded  by  the  simpler  drift  tracts.' 

During  the  field  season  of  1886  the  study  was  extended  out  for  a  dis- 
tance of  60  to  100  miles  from  the  head  of  Lake  Michigan  in  Illinois  and 
Indiana,  a  division  of  the  district  being  made  so  that  each  person  worked  a 
separate  area.  Since  that  season  the  field  work  has  been  largely  carried  on 
by  Professor  Salisbury  and  the  writer,  though  Professor  Chamberlin  has 
constantly  superintended  the  work  and  has  from  time  to  time  visited  the 
field.  Professor  Salisbury's  work,  since  the  first  season,  has  been  largely 
in  southern  and  western  Illinois,  while  the  writer's  has  been  mainly  in  the 
northern  half  of  the  State.  During  the  autumn  of  1892,  however,  the 
writer  was  detailed  to  collect  soils  and  prepare  a  soil  map  of  Illinois  for  the 
Illinois  Board  of  World's  Fair  Commissioners.  This  study  necessitated  a 
reconnaissance  of  the  southern  portion  of  the  State.  This  reconnaissance 
has  been  supplemented  by  more  detailed  studies  in  1894  and  1896.  The 
field  work  carried  on  by  the  writer  in  the  region  under  discussion  has 
been  done  mainly  in  the  field  seasons  of  1886,  1887,  1892,  1894,  1896,  and 
1897.  In  the  intervening  years  the  same  line  of  study  was  extended  into 
bordering  districts,  and  the  broadening  of  the  field  has  resulted  in  a  better 
understanding  of  the  features  of  this  region.  In  the  preparation  of  this 
report,  and  also  throughout  the  field  study.  Professor  Chamberlin  has  given 
constant  advice  and  direction.  The  report  really  embraces  the  information 
obtained  by  Professor  Chamberlin  in  his  early  reconnaissances,  and  the  best 
fruits  of  his  wider  studies,  and  of  the  studies  of  his  other  associates,  as  well 

'Eighth  AnD.  Kept.  U.  S.  Geol.  Survey  (for  1886-87),  1889,  p.  141. 


4  THE  ILLINOIS  GLACIAL  LOBE. 

as  the  data  directly  obtained  by  the  writer.     It  is  with  gratitude  as  well  as 
with  pleasure  that  this  acknowledgment  of  indebtedness  is  made. 

In  this  investio-atiou  there  have  been  several  distinct  lines  of  observa- 
tion,  which  supplement  one  another  in  throwing  light  upon  the  glacial 
succession.  (1)  The  work  began  with  a  mapping  of  moraines,  and  this  map- 
ping has  been  can-ied  to  completion,  i.  e.,  each  moraine  has  been  followed 
thi'oughout  its  entire  course  with  sufficient  zigzagging  to  leam  its  breadth 
and  general  features  as  well  as  the  position  of  the  crest.  (2)  With  this 
study  of  the  moraines  there  has  been  carried  on  an  investigation  of  the 
stratigraphy  of  the  drift,  shown  by  well  sections  or  other  exposures,  both 
artificial  and  natural.  Several  thousand  well  sections  have  been  collected, 
many  of  which  appear  in  tabulated  form  in  this  report.  The  mode  of 
deposition  of  the  glacial  drift  is  such  that  a  simple  study  of  the  drift  sheets 
in  a  vertical  series  can  not,  in  many  cases,  furnish  index  of  the  glacial  suc- 
cession. The  mapping  of  the  moraines  has  often  aided  greatly  in  working 
out  the  full  glacial  succession.  (3)  Coupled  with  the  stratigraphic  study 
and  the  mapping  of  the  moraines  there  have  been  a  few  measurements  and 
estimates  of  the  relative  amounts  of  erosion  or  other  surface  changes  in  the 
drift  in  different  parts  of  the  drift-covered  area,  a  study  which  aims  to  throw 
light  upon  the  relative  ages  of  different  drift  sheets. 

Since  the  townships  are  frequently  referred  to  by  number  and  range, 
rather  than  by  the  civil  name  applied  to  them,  a  brief  explanation  of  the 
method  of  numbering  townships  in  this  region  is  here  presented,  together 
with  a  map  (PI.  II)  showing  base  lines  and  principal  meridians.  The  expla- 
nation begins  with  the  Second  Principal  Meridian  adopted  by  the  United 
States  Land  Survey,  since  the  First  Principal  Meridian  (which  follows  the 
State  line  of  Ohio  and  Indiana)  was  not  used  as  a  basis  for  laying'  out  any 
portion  of  the  region  under  discussion. 

The  Second  Principal  Meridian  leads  north  to  south  through  west- 
central  Indiana  from  the  line  of  Michigan  to  the  Ohio  River,  and  is  situated 
about  2  miles  east  of  longitude  86°  30'  west  from  Grreenwich.  The  base 
line  crosses  the  southern  portion  of  Indiana  within  1  or  2  miles  south  of 
latitude  38°  30'.  The  townships  are  numbered  both  north  and  south  from 
this  base  line.  The  State  of  Indiana  only  extends  to  T.  9  S.,  but  reaches 
T.  38  N.  of  the  base  line.  The  ranges  ai-e  numbered  both  east  and  west 
from  the  Second  Principal  Meridian.     Tliose  on  the  east  extend  to  the  State 


U.S. GEOLOGICAL  SURVEY. 


MONOGRAPH  XXXVIII  PL. II 


JULIUS  Bl  EN  SCO.  LITH    NY 


INTRODUCTION.  5 

line  of  Indiana  and  Ohio,  while  those  on  the  west  have  an  irregular 
boundary.  From  the  head  of  Lake  Michigan  southward  nearly  to  latitude 
41°  the  west  boundary  is  at  the  State  line  of  Indiana  and  Illinois,  but 
south  from  this  line  it  extends  west  into  Illinois  about  25  miles,  being  very 
near  longitude  88°. 

The  Third  Principal  Meridian  leads  north  from  the  mouth  of  the  Ohio 
River  to  the  Wisconsin  line.  It  is  about  8  miles  west  of  longitude  89°. 
The  base  line  is  a  direct  continuation  of  the  base  line  of  the  second  merid- 
ian survey  in  southern  Indiana.  It  enters  Illinois  from  Indiana  just  north 
of  the  city  of  Mount  Carmel  and  touches  the  south  part  of  Centralia  and 
Belleville,  coming  to  the  Mississippi  River  immediately  below  St.  Louis. 
There  are  17  townships  south  of  the  base  line  and  46  north  of  it.  From 
the  north  line  of  the  State  soiith  to  the  Illinois  River  at  Peru  the  ranges  lie 
entirely  east  of  the  Third  Principal  Meridian,  but  south  from  that  stream 
the  ranges  are  numbered  both  to  the  east  and  to  the  west.  To  the  east  they 
extend  to  the  western  limits  of  the  survey  based  on  the  Second  Principal 
Meridian;  to  the  west  they  extend  to  the  Illinois  River  above  the  mouth  of 
that  stream  and  to  the  Mississippi  River  south  from  the  mouth  of  the 
Illinois. 

The  Fourth  Principal  Meridian  leads  fi-om  the  Illinois  River  at  Beards- 
town  north  to  the  Mississippi  River  about  8  milefe  above  Rock  Island,  and  is 
continued  in  western  Jo  Daviess  County.  The  base  line  leads  directly 
west  from  Beardstown  to  the  Mississippi  River,  6  miles  above  Quincy,  and 
is  situated  about  2  miles  north  of  the  fortieth  parallel  of  latitude.  The 
townships  south  of  the  base  line  reach  the  number  14,  while  those  north 
reach  29.  The  ranges  are  numbered  both  to  the  east  and  to  the  west  of  the 
principal  meridian,  north  from  Beardstown;  south  from  that  city  they  are 
numbered  only  to  the  west. 

In  Iowa  and  Missouri,  together  with  several  other  States  west  of  the 
Mississippi,  the  land  surveys  are  governed  by  the  Fifth  Principal  Meridian, 
which  leads  from  the  mouth  of  the  Arkansas  River  north  through  eastern 
Arkansas,  eastern  Missouri,  and  eastern  Iowa.  The  base  line  crosses  cen- 
tral Arkansas,  passing  just  south  of  the  city  of  Little  Rock.  From  this 
base  line  the  townships  are  numbered  to  the  south  as  far  as  the  line  of 
Arkansas  and  Louisiana.  They  are  numbered  to  the  north  as  far  as  the 
international  boundary  in  western  Minnesota  and  north  Dakota.     Eastern 


6  THE  ILLINOIS  GLACIAL  LOBE. 

Minnesota  and  Wisconsin  are  laid  out  from  the  Fourth  Principal  Meridian, 
the  townshijis  being  numbered  from  the  State  line  of  Illinois  and  Wisconsin 
northward  to  the  international  boundary  in  Minnesota  and  Wisconsin,  and 
to  the  line  of  Michigan  and  Wisconsin  in  eastern  Wisconsin. 

The  State  of  Michigan  is  laid  out  from  the  Michigan  meridian,  which 
leads  from  Sault  Ste.  Marie  south  to  the  Ohio  State  line.  The  base  line 
follows  the  parallel  42°  30'.  The  numbering  of  townships  north  from  the 
base  line  harmonizes  with  those  laid  out  from  the  Fourth  Principal  Meridian 
in  Wisconsin  and  Minnesota.  The  ranges  are  numbered  both  to  the  east 
and  to  the  west  of  the  principal  meridian  as  far  as  the  limits  of  the  State. 

In  each  township  there  are  36  sections,  numbered  back  and  forth  in 
tiers  of  six,  the  numbering  beginning  at  the  northeast  and  terminating  at 
the  southeast  corner  of  the  township. 


CHAPTEE   II. 
PHYSICAL  FEATURES. 

Before  eutering  upon  a  discussion  of  the  glacial  deposits,  tlie  leading 
physiograpliic  features  of  the  region  will  be  outlined.  The  region  invaded 
b}^  the  Illinois  lobe  occupies  the  midst  of  the  great  interior  basin  which  on 
the  east  rises  to  the  Appalachian  Mountains  and  on  the  west  to  the  Rocky 
Mountains.  The  State  of  Illinois  has  the  distinction  of  being  the  lowest  of 
the  North-Central  States.  Its  mean  elevation  has  been  estimated  by  Mr. 
Hemy  Gannett  to  be  about  600  feet  above  tide,  while  that  of  Indiana  is 
700  feet,  Michigan  900  feet,  Wisconsin  1,050  feet,  Iowa  1,100  feet,  and 
Missouri  800  feet' 

Including  the  south  end  of  the  Lake  Michigan  basin,  the  region  cov- 
ered by  the  Illmois  lobe  shows  a  range  of  not  far  from  1,200  feet,  the 
bottom  of  the  lake  opposite  Racine,  Wisconsin,  being  at  sea  level,  while 
the  highest  rock  surfaces  of  Illinois  covered  by  glacial  drift  are  nearly 
1,200  feet  above  sea  level.  It  is  not  unlikely  that  glacial  erosion  and  differ- 
ential depression  have  increased  this  range,  but  there  is  reason  to  think  that 
in  preglacial  times  the  lake  basin  was  at  least  several  huudi-ed  feet  lower 
than  the  highest  ridges  of  the  border  districts  and  that  it  had  a  controlling 
influence  upon  the  course  of  the  ice  movement.^ 

The  State  of  Illinois  has  been  covered  by  a  careful  barometric  survey 
conducted  by  Prof  C.  W.  Rolfe,  of  the  University  of  Illinois,  a  survey 
which  had  for  its  object  the  preparation  of  a  topographic  model  of  the  State 
for  the  Columbian  Exposition.  Professor  Rolfe  used  as  datum  points  the 
altitudes  of  railway  stations  which  had  been  determined  by  surveyor's  level. 
These  are  found  at  intervals  so  frequent  in  nearly  every  county  of  the  State 
that  there  is  but  little  room  for  error  in  his  maps.     He  has  exercised  great 

'The  average  elevation  of  the  United  States,  by  Henry  Gannett:  Thirteenth  Ann.  Rept.  U.  S. 
Geol.  Survey,  1892,  p.  289. 

=  See  discussion  by  R.  D.  Irving:  Geol.  of  Wisconsin,  Vol.  II,  1877,  pp.  632-634.  Also  T.  C. 
Chamberlin:  Ann.  Rept.  AVisconsin  Geol.  Survey,  1878,  pp.  23-32. 


8  THE  ILLINOIS  GLACIAL  LOBE. 

care  in  reducing  to  a  minimum  eiTors  arising  from  barometiic  fluctuations. 
He  has  kindly  allowed  the  writer  to  trace  from  liis  unpublished  map  sheets 
such  contours  as  are  represented  on  the  accompanying  map  (PI.  III).  In 
the  hilly-driftless  tracts  in  the  northwest  corner,  and  in  the  southern  end  of 
the  State,  the  sm-face  is  so  uneven  that  only  100-foot  contom-s  are  intro- 
duced. But  the  altitude  of  the  greater  part  of  the  State  is  represented  by 
contours  Avith  50-foot  interval.  For  very  small  areas,  covering  but  a  frac- 
tion of  a  square  mile,  the  contours  must  necessarily  be  omitted  on  a  map  of 
so  small  scale.  A  few  such  areas  occur  in  the  hilly  disti-icts  in  the  noi-th- 
westem  and  the  southern  portions  of  the  State.  In  PL  IV  the  areas 
between  each  100-foot  contour  are  shown  m  color,  and  the  bottom  of  Lake 
Michigan  is  also  represented. 

In  a  general  way  the  altitude  decreases  from  north  to  south  in  the 
State  of  Illinois,  there  being  four  counties  on  the  north  border  (Jo  Daviess, 
Stephenson,  Boone,  and  McHemy)  in  which  points  rise  1,000  feet  above 
tide.  Near  the  southern  border  of  the  Coal  Measures  basin  the  average 
altitude  is  below  500  feet.  There  is,  however,  south  from  the  Coal  Meas- 
ures basin  a  prominent  ridge  which  rises  neai-ly  to  the  altitude  of  the 
northern  portion  of  the  State,  its  crest  reaching  at  one  point  an  altitude 
of  1,047  feet  (Rolfe).  A  reference  to  Pis.  Ill  and  IV  will  make  cleai' 
the  altitudes  and  slopes  of  Illinois  and  also  of  the  portions  of  southwestern 
Michigan  and  western  Indiana  embraced  in  this  discussion.  The  highest 
point  in  Illinois  (1,257  feet)  is  Charles  Moimd,  on  the  Illinois- Wisconsin 
line,  in  the  northwest  county.  The  lowest  points  are  near  the  junction  of 
the  Ohio  and  Mississippi,  and  fall  slightly  below  300  feet  at  low-water 
stages  of  the  sti'eam.  At  high-water  stages  none  of  Illinois  is  below  300 
feet.  It  appears  from  the  table  below  (p.  12)  that  only  125  square  miles, 
or  an  area  of  less  than  four  townships,  rises  above  the  1,000-foot  contoiu-, 
and  that  only  10,747  square  miles,  or  less  than  one-fifth  of  the  State,  falls 
below  the  500-foot  contour.  About  20,000  square  miles,  or  more  than 
one-third  of  the  State,  stands  at  600  to  700  feet  above  tide,  or  at  about  the 
average  altitude  of  the  State. 

The  thickness  of  the  di-ift  is  so  great  in  the  northeastern  fourth  of  Illinois 
as  to  convey  a  false  idea  of  the  altitude  of  the  rock  surtace  in  that  i:egiou. 
Were  the  tbift  coating  entirely  removed,  the  average  elevation  would  prob- 
ably be  as  low  as  the  surface  of  Lake  Michigan  (580  feet  above  tide),  and 


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PHYSICAL  PBATUEBS  OF  THE  EEGION. 


9 


possibly  it  would  not  exceed  500  feet  above  tide.  This  low  altitude  extends 
eastward  some  distance  into  Indiana.  The  low  altitude  of  this  district,  as 
well  as  that  of  the  Lake  Michigan  basin,  as  noted  above,  probably  influ- 
enced the  ice  flow  and  invited  its  great  southward  extension  in  the  State  of 
Illinois. 

The  following  table  showing  the  range  in  altitude  of  the  drift  surface 
and  of  the  rock  floor  in  each  county  of  Illinois  serves  to  show  not  only  the 
general  range  but  also  the  variations  within  small  districts.  As  the  impres- 
sion prevails  widely  that  Illinois  is  a  very  level  region,  the  table  may  be  of 
service  in  dispelling  this  illusion.  The  impression  of  flatness  arises  from 
the  general  absence  of  abrupt  reliefs.  A  comparison  of  the  ranges  in 
altitude  iu  the  several  counties  shows  that  18  counties  have  a  range  of  over 
400  feet  in  their  drift  surface  and  that  22  show  an  equally  great  range  in 
rock  surface.  In  55  coiinties,  or  more  than  half  the  number  in  the  State, 
there  is  a  range  of  less  than  300  feet  in  the  drift  surface,  while  in  62  coun- 
ties the  known  range  in  rock  surface  falls  below  300  feet.  In  the  remaining 
29  counties  the  range  in  altitude  of  drift  surface  falls  below  200  feet. 

Table  showing  altitudes  of  drift  surface  and  rock  floor,  icith  their  range,  in  each  county 

of  Illinois,  (a) 


County. 


Highest 
point. 

Highest 

known  rock 

surface. 

Lowest 
point. 

Lowest 

known  rock 

surface. 

1,257 

1,257 

575 

453 

1,170 

1,170 

735 

(500) 

990 

975 

680 

(425) 

1,040 

1,000 

720 

(450) 

1,040 

875 

740 

580 

913 

607 

581 

505 

910 

699 

581 

478 

812 

680 

581 

581 

975 

760 

614 

579 

950 

813 

649 

542 

1,000 

1,000 

660 

(400) 

1,017 

875 

649 

(400) 

1,020 

1,000 

568 

435 

890 

850 

564 

435 

840 

675 

530 

(425) 

857 

736 

523 

(385) 

850 

815 

562 

560 

987 

800 

431 

330 

Kange  in 
drift  sur- 
face. 


Range  in 
rock  sur- 
face. 


Jo  Daviess  . . 
Stephenson. . 
Winnebago. . 

Boone 

McHenry 

Lake 

Cook 

Dupage 

Kane 

Dekalb 

Ogle.... 

Lee 

Carroll 

Wbiteaide... 
Eock  Island - 

Mercer 

Henry 

Bureau 


(?) 
435 
310 
320 
300 
332 
329 
231 
361 
301 
340 
360 
452 
326 
310 
334 
288 
556 


804 

(670) 

(550) 

(550) 

295 

102 

221 

99 

181 

271 

(600) 

(475) 

565 

415 

(250) 

(351) 

255 

470 


a  Altitudes  of  rock  surface  in  parentheses  have  been  inferred  from  known  altitudes  in  bordering  counties. 


10 


THE  ILLINOIS  GLACIAL  LOBE. 

Table  showimj  altitudes  of  drift  surface  and  rock  floor,  etc. — Continued. 


County. 


Putnam 

Lasalle 

Kendall 

Grundj- 

Will 

Kankakee 

Iroquois 

Ford 

Livingston . . . 

McLean 

Tazewell 

Woodford 

Marsball  . 

Stark , 

Peoria 

Knox 

Warren , 

Henderson  . . . 

Hancock 

McDonough  . 

Fulton 

Adams 

Schuyler 

Brown 

Mason 

Cass 

Menard 

Logan  

Dewitt 

Macon 

Piatt 

Champaign  . 
A'^ermilion  ... 

Edgar 

Clark  

Cumberland . 

Coles 

Douglas 

Moultrie 

Shelby 

Christian  ..  . 
Sangamon . . . 


Highest 
point. 


740 

930 

760 

700 

820 

750 

780 

840 

840 

913 

820 

830 

895 

850 

835 

850 

810 

770 

765 

775 

750 

750 

750 

807 

650 

690 

650 

744 

800 

760 

820 

830 

790 

839 

770 

700 

799 

725 

750 

770 

750 

721) 


Highest 

known  rock 

surface. 


565 

680 

640 

552 

700 

690 

615 

561 

688 

700 

575 

621 

585 

800 

780 

800 

750 

670 

685 

680 

740 

735 

645 

710 

371 

550 

600 

550 

541 

556 

480 

676 

650 

652 

620 

600 

635 

481 

490 

625 

650 

707 


Lowest 
point. 


Lowest 

known  rock 

surface. 


430 
433 
540 
477 
485 
550 
650 
650 
588 
650 
425 
429 
430 
620 
425 
536 
(?) 
505 
46S 
500 
422 
452 
417 
414 
420 
415 
445 
520 
585 
550 
600 
610 
480 
480 
430 
510 
575 
610 
560 
490 
530 
512 


330 

330 

509 

465 

485 

538 

260(?) 

350 

365 

469  — 

325 
(325) 
(325) 

600 

341 

536 

450 
(375) 
(375) 

500 
(325) 
(350) 
(345) 
(345) 
(325) 

345 
(325) 

379  — 

359  — 

400 

480 

440 

436 

480 

(355) 

510  — 

538  — 

481 
490 

538  — 

497 

512 


Range  in 
drift  sur- 
face. 


(? 


310 
497 
220 
223 
335 
200 
180 
190 
252 
263 
395 
401 
465 
230 
410 
314 

:?) 

265 
297 
275 
328 
398 
333 
393 
230 
275 
205 
224 
215 
210 
220 
220 
310 
359 
340 
190 
224 
115 
190 
280 
220 
208 


Bange  in 
rock  sur- 
face. 


235 

350 

131 
97 

215 

152 

355(?) 

211 

323 

231  + 

250 
(296) 
(260) 

200 

439 

264 

300 
(295) 
(310) 

180 
(415) 
(385) 

300 
(365) 

(46) 

205 

(275) 

171  + 

182  + 

156 
(f^ 

236 

214 

172 

(265) 
90  + 
97  + 
(?) 

(?) 
87  + 
135 
195 


PHYSICAL  FEATURES  OF  THE  REGION. 


11 


Table  showing  altitudes  of  drift  surface  and  rock  floor  ^  etc. — Continued. 


County. 


Morgan 

Scott 

Pike 

Calhoun 

Jersey 

Greene 

Macoupin  — 
Montgomery 

Madison 

Bond 

Fayette 

Effingham... 

Jasper  

Crawford  -.. 

Lawrence 

Richland 

Clay 

Marion 

Clinton 

St.  Clair  .... 

Monroe 

Randolph  ... 
Washington . 

Perry 

Jefferson 

Wayne 

Edwards 

Wabash 

White 

Hamilton  ... 

Franklin 

Jackson 

Williamson  . 

Saline 

Gallatin 

Hardin 

Pope 

Massac 

Johnson 

Union 

Alexander... 
Pulaski 


Highest 
point. 


(? 


737 
714 

880 
810 
830 

:?) 

740 
750 
650 
675 
650 
680 
660 
590 
500 
590 
650 
650 
570 
758 
750 
712 
580 
575 
620 
540 
560 
615 
590 
616 
550 
860 
750 
864 
810 
810 
:,047 
550 
800 
985 
619 
489 


Highest 

known  rock 

surface. 


665 
637' 
800 
775 
800 
616 
672 
662 
600 
600 
600? 
650 
600 
550 
490 
510 
600 
G35 
500 
735 
740 
675 
580 
575 
600 
430 
560 
615 
590 
616 
500 
850 
750 
864 
810 
810 
■1,047 
550 
800 
985 
619 
489 


Lowest 
point. 


413 
410 
408 
403 
391 
404 
500 
530 
381 
450 
435 
476 
410 
400 
391 
385 
396 
435 
378 
375 
360 
340 
378 
385 
415 
368 
370 
365 
323 
340 
380 
323 
370 
350 
304 
298 
290 
280 
335 
296 
279 
279 


Lowest 

known  rock 

surface. 


(345) 
(345) 

325  - 
(300)- 
(300) 
(300) 

440  - 

527 

284 

351 

405 

476  - 

395  - 
350 

(345) 
385  - 

396  - 
379 
375  - 
284 
350  - 
340  - 
375  - 
380  - 
415  - 
368  - 
344  - 

344  - 
323  - 
340  - 
375  - 
318  - 
370  - 

345  - 
240 
290  - 
280  - 
270  - 
330  - 
260  - 
270  - 
270  - 


Eange  in 
drift  sur- 
face. 


(? 


324 

■304 
472 

:?) 

439 

(?) 
240 
220 
269 
225 
215 
204 
250 
190 
109 
205 
254 
215 
192 
383 
390 
372 
202 
190 
205 
172 
190 
250 
267 
276 
170 

(?) 
(?) 
(?) 
(?) 


Eange  in 
rock  sur- 
face. 


(320) 
(292) 

475  + 
(475)+ 
(500) 
(316) 

232  + 

135 

316 

249 

195 

174  + 

205  + 

200 
(145) 

125  + 

204  + 
256 
125  + 
451 

390  + 
335  + 

205  + 
195  + 
185  + 
162  + 
216  + 
271  + 
267  -f 
276  + 
125  + 
532  + 
380  + 

519  + 
570 

520  + 
767  + 
280  + 
470  + 
725  + 
349  + 
219  + 


12  THE  ILLINOIS  GLAGIAL  LOBE. 

From  Professor  Rolfe's  maps  estimates  have  been  made  of  the  areas 
between  each  100-foot  contom-  in  each  county,  and  the  results  combined 
for  the  entire  State.  By  these  estimates  the  average  altitude  of  the  State 
is  633.55  feet,  or  but  a  few  feet  different  from  the  estimate  made  by  Mr. 
Gannett.  The  average  thickness  of  drift  in  the  State  is  estimated  to  be 
between  100  and  130  feet.  (See  discussion,  Chapter  XIII.)  If  the  thick- 
ness of  the  di-ift  be  deducted,  the  average  altitude  of  the  rock  sm-face  in 
the  State  will  be  about  525  feet,  or  fully  50  feet  below  the  surface  of  Lake 
Michigan.  The  following  table  gives  the  estimated  areas  between  100-foot 
contours  for  the  entire  State: 

Estimated  areas  in  Illinois  heticeen  100-foot  contours. 

Square  miles. 
Above  1,200  feet 1 

Between  1,100  and  1,200  feet 6 

Between  1,000  and  1,100  feet 118 

Between  900  and  1,000  feet 1  009 

Between  800  and  900  feet 3' 981 

Between  700  and  800  feet 11,127 

Between  600  and  700  feet 20  058 

Between  500  and  600  feet 9  603 

Between  400  and  500  feet 8  822 

Between  300  and  400  feet 1^  925 

Area  of  Illinois 56,  650 

As  noted  above,  the  Illinois  lobe  extended  into  western  Micliig-an  and 
western  Indiana,  and  also  into  southeastern  Iowa.  Contour  maps  of  these 
districts  have  not  yet  been  made,  except  in  portions  of  Scott  and  Muscatine 
counties,  Iowa,  covered  by  the  United  States  Geological  Survey  sheets. 
The  numerous  railway  surveys  have,  however,  established  the  altitude  of 
so  many  points  that  a  fair  estimate  of  the  altitude  of  these  districts  ma)-  be 
made.  It  is  found  that  the  drift  surface  has  an  average  altitude  slightly 
higher  than  that  of  Illinois,  but  it  will  scarcely  exceed  650  feet  above  tide. 
The  rock  surface,  on  the  other  hand,  appears  to  be  a  few  feet  lower  than 
the  average  for  Illinois.  The  inclusion  of  these  districts,  therefore,  scarcely 
makes  a  measurable  change  in  the  average  altitude  of  the  region  covered 
by  the  Illinois  lobe.  But  if  the  Lake  Michigan  basin  be  included,  it  wil' 
materially  lower  the  average  altitude. 

Profiles  across  the  basin  of  Lake  Michigan  have  been  prepared  from 
Lake  Survey  charts  which  bring  out  certain  prominent  features  of  the 
southern  end  of  the  Lake  Michigan  basin  as  it  now  appears  with  its  coating 


U.S. GEOLOGICAL  SURVEY 


MONOGRAPH  XXXVIH.PL.V. 


Profile  across  Lake  Michigan  in  latitude  44-°  15' 


Pleistocene  640  feet 


Davonian  shale320  feet 
Devonian  /imestone 


Surface  of  lake  573.6  feet 


Profile  across  Lake  Michigan  from  Sheboygan  to  Little  Sable  Point 


'BE^ONHARaOR 


Surface  of  lake  573.6  feet 


POSITIONS  OFSECTIONS 


J^Muske^nUk8%. 


^ecfoflakP. 


Pleistocene 
Eo-Carboniferous 


\Dnrt22S  feat 

irly  sandstone 


Profile  across  Lake  Michigan  from  Port  Washington  to  Muskegon 


Surface  of  lake  579.6  feef. 


Bedof  fakf> 


istSceneSZAOrift  179  fbet 
miferous^ — ^Sane/stone  76 


Sandstone  76  feet 


Profile  across  Lake  Michigan  from  Milwaukee  to  Grand  Haven 


Surface  of  lake  573.6  feet. 


Profile  across  Lake  Michigan  from  Racine  to  Holland 


t    I   ^     ?s^> 

^      Q,    <:        <5!??  ^ 


Surface  of  lake  573.6  feet 


Profile  across  Lake  Michigan  from    Fox  Lake  to  Keeler 


■u  JO 

ti 


Upper  Silurian). 
LowerSilurian\ 


Surface  of  lake  579.6  feet 


•roup 

'ver  ^roup 
'fnestone 


Bed  of  take 


Ydh^4- 

I  Blue  shafe 
\Black  sttale 
A/iamilton  limestone 


Profile  across  Lake  Michigan  from  Chicago  to  Benton  Harbor 


JULIUS  Bl  EN  &  CO,  LITH.  N.> 


PROFILES  ACROSS  THE  BED  OF  LAKE  MICHIGAN 

(Based  on  soundings  given  in  the  UnitedStateslake  SurreyCharts  ) 

BY 

FFIANK  LEVERETT 

1898. 


PHYSICAL  FEATUEES  OF  THE  REGION.  13 

of  drift  (see  PI.  V).  The  first  two  profiles  show  a  gradual  slope  from  the 
west  side  to  points  beyond  the  middle  of  the  lake,  followed  by  a  somewhat 
abrupt  rise  to  the  east  shore.  The  amount  of  di-ift  on  the  east  shore  is 
somewhat  greater  than  on  the  west,  the  rock  floor  at  St.  Joseph  being  but 
466  feet  above  tide,  or  124  feet  below  the  lake,  while  on  the  west  shore  it 
rises  in  many  places  20  or  30  feet  above  the  lake  level  and  generally  is  not 
far  below  it.  The  next  profile  leading  eastward  from  Racine  passes  across 
the  deepest  part  of  the  basin  in  the  southern  end  of  Lake  Michigan,  and 
shows  no  essential  difference  on  opposite  sides  of  the  lake  in  the  slope  of 
the  lake  bottom.  The  slopes  and  bottom  are  A^ery  smooth  compared  with 
those  shown  in  profiles  farther  north.  The  profile  leading  from  Milwaukee 
to  Grand  Haven  shows  a  much  shallower  part  of  the  basin  than  that  east 
from  Racine,  the  altitude  being  nowhere  below  200  feet  above  tide,  while 
opposite  Racine  it  reaches  sea  level.  This  line  between  Milwaukee  and 
Grrand  Haven  seems  to  mark  nearly  the  summit  of  a  ridge  between  two 
basins,  both  of  which,  together  with  the  dividing  ridge,  are  covered  by  the 
lake.  In  the  profile  a  few  miles  to  the  north,  leading  from  Port  Washington, 
Wisconsin,  to  Muskegon,  Michigan,  the  lake  bottom  is  shown  to  be  singu- 
larly irregular.  The  appearance  presented  is  that  of  a  series  of  escarp- 
ments facing  westward,  similar  to  the  escarpment  of  Lockport  (commonly 
known  as  Niagara)  limestone  a  short  distance  west  from  Lake  Michigan, 
biit  it  is  not  entirely  certain  that  they  are  rock  escarpments.  Were  the 
drift  to  be  removed  from  the  eastern  border  of  the  basin  the  profile  would 
be  quite  different.  A  well  at  Muskegon,  reported  by  the  Michigan  Geo- 
logical Survey,  has  235  feet  of  di'ift,  which  brings  the  rock  floor  down  to 
an  altitude  but  360  feet  above  tide,  or  only  a  few  feet  above  the  crests  of 
the  ridges  in  the  midst  of  the  lake.  The  dotted  line  at  the  right  of  the 
profile  indicates  the  depth  of  the  di-ift  at  that  point.  The  profiles  north 
from  this  line  show  irregularities  of  lake  bottom  which  give  it  the  appear- 
ance of  being  channeled  longitudinally.  Whether  these  irregularities  are 
due  to  drift  accumulations  or  to  rock  ridges  is  not  manifest  fi-om  an  inspec- 
tion of  the  lake  charts.  The  remarkable  thickness  of  drift  at  Manistee  (640 
feet)  is  worthy  of  note,  and  indicates  that  the  abrupt  border  of  the  lake 
there  is  of  diift. 

Evidence  that  the  present  smooth  bottom  of  the  Lake  Michigan  basin 
in  its  southern  end  is  due  to  the  planeness  of  the  drift  surface  instead  of  the 


14  THE  ILLINOIS  GLACIAL  LOBE. 

smootliness  of  the  rock  floor  is  found  in  borings  near  Michigan  City.  Three 
borings  in  a  line  leading  ft-om  Michigan  City  westward  2  miles  show  a  ridge 
capped  by  Devonian  shale  at  the  middle  boring,  which  stands  70  or  80  feet 
above  a  rock  floor  of  limestone  at  the  other  wells. 

Taking  the  basin  as  a  whole,  interesting  contrasts  appear.  The 
remai-kable  depth  and  the  smoothness  of  the  south-central  portion  of  the 
basin  shown  in  the  profile  east  from  Racine  seem  to  favor  the  view  that 
glacial  erosion  was  there  an  agency  of  much  consequence.  The  preserva- 
tion of  the  shale  at  Michigan  City  (a  few  miles  to  the  south)  and  the 
apparent  preservation  of  old  escarpments  in  the  midst  of  the  basin  a  few 
miles  to  the  north,  both  being  in  more  prominent  and  apparently  better 
exposed  situations  for  eff'ective  erosion  than  the  deep  part  between  them, 
seem  to  show  comparatively  little  erosion.  The  evidence  therefore  as  to 
the  amount  of  glacial  erosion  is  somewhat  confusing,  and  it  will  be  found 
difficult  to  eliminate  this  factor  if  an  attempt  to  restore  the  preglacial 
features  of  the  basin  be  made. 

The  reliefs  of  the  region  covered  by  the  Illinois  lobe  are  seldom  of  a 
bold  or  conspicuous  type.  On  the  contrary,  they  are  so  gradual  as  to  give 
the  impression  that  they  are  less  than  the  instrumental  determinations  indi- 
cate. There  are,  however,  a  few  ridges  with  rock  nuclei  which  are  of 
sufficient  prominence  to  merit  notice. 

The  most  prominent  ridge  of  the  region  is  found  in  the  southern  por- 
tion of  Ilhnois,  at  the  southern  border  of  the  glaciated  district.  This  ridge 
crosses  the  State  in  a  direction  nearly  due  east  and  west  from  the  bend  in 
the  Ohio  River  just  south  of  the  mouth  of  the  Wabash  to  the  Mississippi 
River  near  Grand  Tower.  Its  crest  ranges  from  about  700  to  1,047  feet 
above  tide  (Rolfe),  and  its  breadth  ranges  fi-om  5  or  6  to  10  or  12  miles. 
It  stands  300  to  600  feet  alcove  the  lowlands  on  the  north,  their  altitude 
being  but  400  to  550  feet  above  tide,  and  an  even  greater  amount  above  the 
lowest  parts  of  the  district  on  the  south.  This  ridge  seems  to  have  limited 
the  extension  of  the  ice  sheet,  for  the  di-ift  was  carried  well  up  toward  the 
crest  on  the  north  slope,  but  no  decisive  e^^dence  has  been  found  that  the 
crest  was  overridden. 

From  the  western  end  of  the  ridge  just  noted,  northwestward  along 
the  Mississippi  to  St.  Louis,  an  elevated  limestone  belt  separates  the  river 
valley  from  the  Coal  Measm-es  district  to  the  northeast.     This  belt  is  but 


PHYSICAL  FEATURES  OF  THE  EEGION.  15 

5  to  10  miles  wide  and  stands  650  to  750  feet  above  tide,  while  the  Coal 
Measures  district  bordering  it  stands  only  450  to  600  feet  above  tide.  It  is 
inteiTupted  by  gaps  2  miles  or  less  in  width  where  the  Big  Mnddy  and  the 
Kaskaskia  pass  tlii-ough  it  to  the  Mississippi ;  otherwise  it  forms  a  continuous 
belt.  Its  altitudes  are  no  greater  than  those  of  the  district  across  the  river 
in  Missouri.  On  the  contrary,  there  is  a  rise  in  that  direction  to  the  Iron 
Mountain  district  of  southeastern  Missouri.  It  seems  remarkable  that  the 
Mississippi  should  have  taken  a  course  across  this  limestone  belt,  and  as  yet 
no  satisfactory  explanation  for  this  feature  has  been  found.  The  stream  is 
apparently  in  a  preglacial  valley.  Its  course  seems,  therefore,  to  be  inde- 
pendent of  glaciation.  This  belt,  like  the  ridge  of  southern  Illinois,  seems 
to  mark  the  limit  of  the  ice  sheet.  Drift  in  small  amount  occurs  over  most 
of  its  surface,  but,  so  far  as  known  to  the  writer,  does  not  extend  beyond 
the  Mississippi.  Near  St.  Louis,  however,  where  the  limestone  border  passes 
to  the  west  side  of  the  river,  drift  is  found  in  small  amount. 

Passing  up  the  Mississippi  to  the  mouth  of  the  Illinois,  a  naiTow  axis 
of  upheaval  is  found,  trending  nearly  east  and  west,  along  which  the  altitude 
is  somewhat  greater  than  on  bordering  districts.  Just  east  of  the  mouth  of 
the  Illinois  there  are  a  few  points  where  the  rock  surface  rises  to  about  800 
feet,  while  on  the  plain  north  of  this  ridge  the  rock  scarcely  exceeds  650 
feet.  West  from  the  Illinois  the  altitude  is  not  markedly  greater  at  this  axis 
than  to  the  northward,  there  being  a  narrow  limestone  ridge  between  the 
Mississippi  and  the  Illinois  through  the  entire  length  of  Calhoun  County, 
whose  crest  is  generally  700  to  750  feet  above  tide.  The  altitude  of  the 
ridge  west  of  the  Illinois  is  fully  100  feet  greater  than  that  of  the  bluffs 
immediately  east  of  that  stream.  These  elevated  limestone  ridges,  and 
similar  ridges  on  the  Missouri  side  of  the  Mississippi,  near  the  town  of 
Louisiana  and  soiithward,  carry  very  little  drift  and,  as  noted  some  years 
since  by  Salisbury,  may  not  have  been  completely  covered  by  the  ice 
sheet.^ 

Of  the  three  belts  just  described  two  have  been  sculptured  very  deeply 
by  surface  erosion,  viz,  the  ridge  crossing  southern  Illinois  and  the  ridge 
near  the  mouth  of  the  Illinois.  The  remaining  belt  (along  the  Mississippi 
below  St.  Louis)  is  less  deeply  sculptured  because  in  much  of  its  extent 
imderground  drainage  through  sink  holes  and  caves  has  been  established. 

1  Proc.  Am.  Assoc.  Adv.  Sci.,  Vol.  XL,  1891,  pp.  251-253. 


16  THE  ILLINOIS  GLACIAL  LOBE. 

There  is  not  even  a  well-developed  system  of  ravines  and  tributaries  on  its 
surface,  but  ravines  partially  developed  often  discharge  their  waters  into 
sink  holes  and  have  no  surface  indications  of  connection  with  other  lines 
of  di-ainage. 

In  the  northwestern  part  of  Illinois  a  few  conspicuous  outlying  mounds 
of  Lockport  (Niagara)  limestone  appear.  Some  of  these  are  situated  in  the 
di-ift-covered  region  and  others  in  the  Di'iftless  Ai-ea.  They  rise  75  to  300 
feet  above  border  districts.  The  majority  of  these  mounds  rise  above  the 
1,100-foot  contour,  and  one  of  them,  Charles  Mound,  as  noted  above,  forms 
the  highest  point  in  the  State  (1,257  feet).  They  vary  in  size  from  a  fraction 
of  a  mile  to  several  square  miles.  In  the  latter  case  a  chain  of  mounds 
occurs,  rather  than  a  single  mound  or  ridge.  These  mounds  lie  but  a  few 
miles  north  and  east  of  continuous  Niagara  formations  and  were  apparently 
once  joined  with  them,  then-  separation,  as  long  since  stated  by  Worthen, 
being  due  to  denudation.^  The  greater  pai't  of  the  district  among  these 
mounds  has  been  denuded  of  the  Hudson  River  or  Maquoketa  shales  as 
well  as  of  the  Lockport  limestone,  thus  exposing  the  Galena  limestone. 

East  from  the  district  just  discussed  is  the  broad  drainage  basin  of 
Rock  River,  which  has  no  conspicuous  ridges  or  remnants  of  higher  sti-ata 
capping  its  present  smface  formations,  though  the  latter  are  thoroughly 
sculptured  by  di-ainage  lines. 

Between  the  Rock  River  di-ainage  line  and  Lake  Michigan  there  is  a 
somewhat  elevated  belt  of  limestone,  wliich  extends  cm-vingly  in  a  dnection 
east  of  south  into  western  Indiana.  It  is  generally  so  hea-saly  covered  with 
drift  that  its  lesser  features  can  only  be  conjectured.  Borings  indicate  that 
A^ariations  of  100  feet  or  more  in  altitude  occur  within  a  distance  of  a  few 
rods.  It  was  in  all  probability  thoroughly  sculptured  by  drainage  lines. 
The  rock  surface  has  its  greatest  altitude  at  the  north,  being  400  feet  above 
Lake  Michigan  at  tlie  Illinois- Wisconsin  line,  while  in  the  "^acinity  of  the 
Indiana  line  it  rises  only  100  to  200  feet  above  the  lake.  The  Fox, 
Des  Plaines,  and  Kankakee  rivers  now  cross  this  limestone  belt  from  the 
k)w  belt  bordering  Lake  ]\Iichigan  into  the  old  Rock  and  Illinois  drainage 
basin,  thus  extending  the  latter  at  the  expense  of  the  former. 

In  southern  Indiana  there  is  a  comparatively  elevated  region  along  the 
east  border  of  the  Coal   Measm-es  formed  largely  by  the  Conglomerate 

'  Geology  of  Illinois,  Vol.  T.  ISOfi.  ,i.  4. 


PHYSICAL  FEATUEES  OP  THE  KEGIOF.  17 

sandstone.  This  was  partially  covered  by  the  ice  sheet.  The  highest 
points  within  the  glaciated  portion  seldom,  if  ever,  exceed  900  feet,  but 
with  this  altitude  they  stand  200  to  300  feet  or  more  above  the  general 
level  of  the  rock  surface  near  the  Wabash,  only  a  few  miles  to  the  west. 
This  sandstone  forms  the  western  border  of  a  broad  tract  of  elevated  land, 
which  is  greatly  eroded  and  hence  is  called  the  "hill  country"  of  Indiana. 
Its  northern  portion  has  had  the  irregularities  greatly  softened  by  glaciation. 
The  southern  portion  was  less  heavily  glaciated  and  is  nearly  as  rough  as 
the  unglaciated  tracts. 

The  district  occupied  by  the  Coal  Measures,  both  in  Illinois  and  in 
Indiana,  has  a  general  altitude  somewhat  lower  than  that  of  the  bordering- 
limestone  or  sandstone.  Prior  to  the  ice  invasion  its  surface  had  been 
greatly  eroded,  leaving  narrow  divides  at  the  water  partings  more  or  less 
dissected  into  low  hills,  while  the  streams  occupied  broad  shallow  troughs. 
These  features  are  only  partially  concealed  in  southern  Illinois  and  south- 
western Indiana.  As  already  noted,  streams  which  flow  from  the  Coal 
Measures  into  the  lower  Carboniferous  limestone  show  a  marked  reduction 
in  the  size  of  the  channel  upon  entering  the  limestone.  This  is  true  not 
only  of  small  rivers  like  the  Kaskaskia,  but  also  of  large  streams.  The 
valley  of  the  Illinois  is  reduced  in  breadth  from  8  or  10  miles  to  scarcely  3 
miles  on  entering  the  limestone  on  the  border  of  Pike  and  Greene  counties. 
The  preglacial  Mississippi,  now  partly  filled  with  drift,  is  narrowed  in 
breadth  from  10  or  12  miles,  or  possibly  15  miles,  in  the  Coal  Measures  of 
Louisa  County,  Iowa,  and  Mercer  County,  Illinois,  to  only  5  or  6  miles  on 
entering  the  limestone  a  few  miles  above  Burlington,  Iowa.  Where  streams 
do  not  enter  the  limestone  a  gradual  widening  occurs  toward  the  mouth. 
The  Wabash  occupies  a  preglacial  valley  in  which  the  breadth  increases 
gradually  southward  and  reaches  10  or  15  miles  in  the  vicinity  of  its  mouth. 
Below  Terre  Haute  the  breadth  varies  from  5  or  6  miles  to  15  miles  or 
more,  and  in  places  the  bluffs  are  very  poorly  defined,  owing-  to  the  fact 
that  the  strata  of  the  bordering  districts  have  broken  down  nearly  as 
rapidly  as  the  valley  was  deepened.  The  several  tributaries  of  the  Wabash 
in  southern  Illinois — the  Embarras,  Bon  Pas,  and  Little  Wabash — have 
broad  trough-like  valleys  2  to  4  miles  in  Avidtli  in  their  lower  courses,  and 
their  bluffs  are  often  vaguely  defined,  like  those  of  the  main  stream. 
MON  xxxviii 2 


18  THE  ILLINOIS  GLACIAL  LOBE. 

Occasional  basin-like  expansions  of  river  valleys  appear  outside  the 
Coal  Measures.  One  formed  in  the  Hudson  River  or  Maquoketa  shales 
and  underlying-  formations  along  the  Pecatonica  Ri-\-er  near  Freeport  has 
a  breadth  of  about  4  miles  where  Avidest,  though  usually  it  is  but  2  or  3 
miles.  This  basin  has  been  discussed  recently  by  Mr.  Oscar  Hershey  as  a 
peneplain/  but  to  the  writer  it  appears  too  immature  to  be  thus  classed.  A 
similar  basin  borders  Elkhorn  Creek  in  Carroll  and  Whiteside  counties. 
The  Mississippi  Valley  also  has  an  expansion  where  it  crosses  these  shales 
on  the  borders  of  Carroll  County,  Illinois,  and  Jackson  County,  Iowa, 
being  fully  twice  as  wide  as  it  is  where  cut  in  the  Galena  or  in  the  Lockport 
(Niagara)  limestone.  These  contrasts  in  width  are  well  shown  in  the 
Clinton,  Savannah,  and  other  topographic  sheets  coA'ering  this  part  of  the 
Mississippi  Valley.     The  Clinton  sheet  appears  as  PI.  XVIII  of  this  report. 

Most  of  the  streams  in  this  region  have  courses  independent  of  the 
preglacial  drainage  lines.  It  is  only  in  the  western  half  and  southern 
third  of  Illinois  and  in  southwestern  Indiana,  where  the  drift  is  compara- 
tively thin,  that  the  course  of  preg'lacial  drainage  can  be  confidently  indi- 
cated. Even  here  the  larger  valleys  only  are  traceable,  for  the  valleys  of 
the  smaller  streams  have  usuall}^  been  completely  filled,  and  deep  borings 
are  too  few  to  supply  data  to  map  out  their  position  and  connections.  The 
effect  of  glaciation  on  the  drainage  will  appear  in  the  progress  of  the 
discussion. 

'  Am.  Geologist,  August,  1896. 


CHAPTER    III. 

OUTLINE  OF  TIME   RELATIONS   OR   GLACIAL    SUCCESSION. 

In  the  progress  of  the  studies  of  glacial  deposits  the  complexity  of  the 
glacial  histor}^  has  been  graduallj-  unfolded.  After  the  abandonment  of 
the  iceberg  hypothesis,  the  early  students  approached  the  study  with  the 
hypothesis  of  a  single  and  practically  continuous  period  of  deposition,  in 
which  the  ice  sheet  at  one  time  covered  the  entire  glaciated  area.  This 
period  was  supposed  to  have  terminated  with  a  suigle  high  stage  of  water, 
attending  the  melting  of  the  ice,  which  was  termed  the  Champlain  epoch. 
It  soon  became  apparent  that  this  simple  hypothesis  could  not  be  made  to 
cover  the  complicated  glacial  history.  Evidences  of  a  succession  of  reces- 
sions and  advances  of  the  ice  sheet  have  appeared,  and  a  sharp  controversy 
has  arisen  concerning  the  importance  of  these  oscillations,  it  being  held  by 
some  students  that  they  are  of  minor  importance  and  mark  short  or  partial 
retreats  and  advances  in  a  single  epoch  of  glaciation,  while  others  have 
contended  for  the  necessity  of  recognizing  two  or  more  ice  invasions 
between  which  were  very  extensive  and  prolonged  deglaciation  intervals. 
The  studies  upon  which  the  present  report  is  based  have  developed  evidence 
which,  it  is  thought,  has  an  important  bearing  upon  the  question  in  dispute. 
The  writer,  like  others  who  have  studied  this  region,  has  been  greatly 
impressed  with  the  evidence  of  prolonged  intervals  of  deglaciation,  and  an 
attempt  will  be  made  to  set  forth  the  nature  of  this  evidence. 

The  several  sheets  of  glacial  drift  which  this  and  neighboring  regions 
contain  have  received  geographic  names,  as  have  also  some  of  the  inter- 
glacial  beds.  Names  of  this  class  were  proposed  by  Chamberlin  as  a  sub- 
stitute for  time  phrases  which  had  arisen  and  which  were  of  controverted 
application.^  They  have  already  come  into  wide  use  in  g'lacial  literature, 
and  are  employed  by  students  who  hold  the  divisions  to  be  of  minor  impor- 
tance as  Avell  as  by  those  who  consider  them  of  great  importance.     The 

'  See  Geikie's  Great  Ice  Age,  third  edition,  1894,  pp.  754-774.     Also  Jour.  GeoL,  Vol.  Ill,  pp. 

270-277,  aud  Vol.  IV,  pp.  872-876. 

19 


20  THE  ILLINOIS  GLACIAL  LOBE. 

cli%asions  to  which  ChamberUn  has  appKed  names  appear  to  have  the  rank 
of  the  main  divisions  of  the  Glacial  period,  whatever  that  rank  may  prove 
to  be.  Other  names  are  necessary  to  denote  the  subdivisions.  In  the  present 
report  several  names  are  thus  introduced  to  designate  the  moraines  associ- 
ated with  the  older  as  well  as  the  newer  sheets  of  drift.  The  name  selected 
is  usually  that  of  a  town  located  on  the  moraine.  In  most  cases  the  names 
have  come  into  use  in  the  office  and  in  correspondence  with  other  glacialists, 
as  a  convenient  form  of  reference.  The  selection  thus  made  seems  suitable 
for  general  use. 

In  the  outline  sriven  below  it  is  aimed  to  cover  the  events  between  the 
deposition  of  the  oldest-recognized  drift  sheet  in  North  America  and  the 
final  recession  of  the  ice  sheet  or  sheets  into  the  region  north  of  the  Great 
Lakes.  The  main  divisions  appear  to  be  much  longer  than  the  secondary 
ones.  It  is  concerning  the  former  that  the  value  of  time  intervals  is  a  mat- 
ter of  dispute.  The  secondary  divisions  of  the  drift  deposit  are  not 
thought  by  any  students  to  be  marked  by  intervals  sufficiently  prolonged 
to  mei-it  the  application  of  the  term  epoch.  It  is  probable,  however,  as 
shown  farther  on,  that  some  oscillation  of  the  ice  front  occurred,  so  that  the 
moi-aines  on  which  these  subdivisions  are  based  do  not  mark  simply  halts 
in  the  recession  of  the  ice,  but  rather  readvances  after  recessions  of  minor 
consequence.  To  avoid  the  use  of  the  controverted  term  epoch,  it  is  thought 
best  to  employ  the  term  stage,  which  gives  a  less  definite  time  value. 

Outline  of  the  drift  sheets  and  intervals. 

Stage  1.  Oldest  recognized  drift  sheet — the  Albertan  of  Dawson,  including,  also,  the  sub-Aftonian 

of  Chamberlin. 
Stage  2.  First  interval  of  deglaciation— Aftonian  of  Chamberlin. 
Stage  3.  Kansan  drift  sheet  of  the  Iowa  geologists. 

Stage  4.  Second  interval  of  recession  or  deglaciation — Yarmouth  of  Leverett. 
Stage  5.  niinoian  drift  sheet. 

Stage  6.  Third  interval  of  recession  or  deglaciation — Sangamon  of  Leverett. 
Stage  7.  lowan  drift  sheet  and  main  loess  deposit. 
Stage  >i.  Fourth  interval  of  recession  or  dealaciatiou — Peorian  of  Leverett,  possibly  equivalent  to  the 

Toronto  Formation  of  Chamberlin. 

Stage  9.  Early  Wisconsin  drift  sheets. 

„  ,    .         ,     c,    1,       -11  •    ■  J.  „  (  Shelhyville  moraine. 

Substage  1.  Shelbyville  morainic  system  |  gerro  Gordo  moraine. 

(  Outer  ridge. 
Substage  2.  Champaign  morainic  system-?  Middle  ridge. 

(  Inner  ridge. 
(  Bloomingtim  or  outer  main  ridge. 
Substage  3.  Bloomiugton  morainic  system  •]  Normal  or  inner  main  ridge. 

(  Subordinate  ridgos. 

„   ,    ^         .    ,.         n  ■    •         ,.       S  Marseilles  moraine. 

Substage  4.  Marseilles  moraimc  system  ^  p„gsi,,,y  Miuooka  till  ridge. 


TIME  EELATIONS  OR  GLACIAL  SUCCESSION.  21 

Stage  10.  Fifth  interval  of  recession,  unnamed;  shown  by  shifting  of  ice  lobes. 
Stage  11.  Late  Wisconsin  drift  sheets. 

Substage  1.  Great  bowlder  belts  and  accompanying  moraines,  including,  perhaps,  the 
Minoota  till  ridge. 

Substage  2.  Valparaiso  morainic  system.  ^ 

Substage  3.  Lake  border  morainic  system. 
Stage  12.  Lake  Chicago  submergence. 
Stage  13.  Emergence  of  plain  covered  by  Lake  Chicago. 
Stage  14.  Partial  resubmergence  of  plain  covered  by  Lake  Chicago. 
Stage  15.  The  iiresent  stage  of  Lake  Michigan. 

The  outline  just  presented  differs  from  the  one  last  presented  by 
Chamberlin^  in  the  separation  of  the  Wisconsin  drift  series  and  lake  history 
into  the  several  substages,  and  the  introduction  of  names  for  three  inter- 
glacial  stages.  Except  for  the  introduction  of  names  for  the  interglacial 
stages,  it  is  essentially  the  same  as  an  outline  presented  by  the  writer  in  a 
recent  bulletin  of  the  Chicago  Academy  of  Sciences.^ 

Mr.  J.  B.  Tyrrell  of  the  Canadian  Geological  Survey,  who  has  studied 
widely  in  western  Canada,  favors  the  separation  of  the  Albertan  and  sub- 
Aftonian  stages.  In  a  letter  to  the  writer  dated  July  9,  1897,  which 
discusses  the  outline  given  in  the  bulletin  just  referred  to,  he  makes  the 
following  statement: 

The  Albertan  drift  sheet  of  Dawson  is  older  than  any  till  of  the  Keewatin 
glacier  seen  in  the  plains  of  northwestern  Canada,  while  the  Upper  and  Lower 
Bowlder  Clay  of  our  Eeports  seem  to  correspond  closely  with  your  Kansau  and  sub- 
Aftonian.     I  should,  therefore,  completely  separate  the  Albertan  and  sub-Aftonian. 

In  the  present  stage  of  investigation  the  correlation  of  the  Upper  and 
Lower  Bowlder  Clays  of  the  Canadian  Reports  with  the  Kansan  and  sub- 
Aftonian  of  southern  Iowa  is  not  worked  out  satisfactorily.  The  full  extent 
of  either  the  Kansan  or  sub-Aftonian  in  districts  lying  between  Iowa  and 
the  Canadian  boundary  is  not  determined.  It  therefore  may  be  hazardous 
to  venture  definite  correlation,  though  the  balance  of  probabilities,  as  sug- 
gested by  Tyrrell,  seems  to  favor  this  correlation  and  the  transference  of 
the  Albertan  to  an  earlier  stage. 

The  complexity  of  the  glacial  history  is  still  further  increased  by  the 
occurrence  of  more  than  one  gathering  ground  or  center  of  dispersion  of 
the  ice.     The  explorations  of  the  Canadian  Survey  have  shown  that  there 

'Jour.  Geol.,  Oct.-Nov.,  1896,  Vol.  IV,  No.  7,  pp.  872-876. 

2  Pleistocene  features  and  deposits  of  the  Chicago  area,  by  Frank  Leverett :  Bull.  Chicago  Acad. 
Soi.  No.  2;  issued  May,  1897. 


22  THE  ILLINOIS  GLACIAL  LOBE. 

were  three  main  centers  of  dispersion  aside  from  Greenland.  The  Cordil- 
lei'au  reg-ion  of  western  Canada  contained  one  ice  field  from  which  there 
was  dispersion  in  all  directions.  The  province  of  Keewatin,  west  of  Hudson 
Bay,  contained  aiiother  ice  field  which  spread  in  all  directions  and  reached 
the  glacial  boundar}^  in  Missouri  and  States  to  the  southwest.  The  third 
ice  field  occupied  the  highlands  east  and  south  of  Hudson  Bay.  It  spread 
to  the  borders  of  the  Atlantic  on  the  north  and  east,  and  to  the  borders  of 
the  Mississippi  and  Ohio  on  the  southwest  and  south.  The  two  ice  fields 
bordering  Hudson  Bay  probably  for  a  time  coalesced  to  form  the  Lauren- 
tide  ice  sheet  of  Dawson.-"  But  they  were  apparently  distinct  and  inde- 
pendent centers  for  a  considerable  part  of  the  Grlacial  period.  The  names 
Keewatin  and  Labrador  seem  appropriate  for  these  independent  centers  of 
glaciation,  the  former  being  a  name  proposed  bj^  Mr.  Tyrrell,  and  the  latter 
one  which  has  been  used  by  several  glacialists  in  correspondence  and  to 
some  extent  in  print.  The  name  Cordilleran  has  been  applied  by  Dawson 
to  the  ice  field  in  western  Canada.  There  appeal's  to  have  been  less  com- 
plete coalescence  of  this  ice  field  with  the  Keewatin  than  that  between  the 
Keewatin  and  Labrador  ice  fields. 

The  Cordilleran  ice  field,  as  shown  by  Dawson,  occupied  a  portion  of 
the  Rocky  Mountains  and  extended  eastward  into  the  pro-\dnce  of  Alberta, 
in  the  early  stage  of  glaciation,  when  the  Albertan  drift  sheet  was 
deposited.-  This  advance  long  preceded  the  maximum  westward  extension 
of  the  Keewatin  ice  field.  Whether  the  sub-Aftonian  or  any  other 
deposits  of  the  Keewatin  ice  sheet  are  as  old  as  the  Albertan,  as  noted 
above,  is  not  satisfactorily  determined. 

The  Keewatin  ice  sheet  apparently  reached  its  farthest  limits  on  the 
borders  of  the  Mississippi  at  the  Kansan  stage  of  glaciation.  The  recogni- 
tion of  the  sub-Aftonian — an  older  deposit  than  the  Kansan — in  southern 
Iowa  is  based  upon  the  exposures  of  this  drift  sheet  under  a  somewhat 
fresher  sheet  of  Kansan  drift.  The  extent  of  the  sub-Aftonian  toward  the 
south  and  west  compared  with  that  of  the  Kansan  is  not  yet  determined. 
In  a  paper  presented  at  the  twelfth  annual  meeting  of  the  Iowa  Academy 
of  Sciences,  in  December,  1897,  Dr.  H.  Foster  Bain,  of  the  Iowa  Greolog 
ical  Survey,  gave  a  careful  review  of  the  features  of  the  sub-Aftonian  and 

1  See  Am.  Geologist,  Vol.  VI,  1890,  pp.  153-161. 

2 Bull.  Gool.  Soc.  America,  Vol.  VII,  pp.  31-(5fi;  issued  November,  1895. 


TIME  RELATIONS  OR  GLACIAL  SUCCESSION.  23 

descriptions  of  the  weathered  zone  between  this  till  sheet  and  the  overlying 
Kansan.  The  extent  of  weathering  appears  to  him  scarcely  sufficient  to 
warrant  a  separation  into  a  distinct  glacial  stage.  He,  however,  suggested 
that  the  sub-Aftonian  sheet  may  have  been  formed  during  one  of  the 
hypothetical  minor  advances  of  the  ice  sheet  preceding  its  maximum 
extension.^ 

The  portion  of  the  Labradorian  ice  field  to  which  the  name  Illinois  Lobe 
is  applied,  reached  its  farthest  limits  on  much,  if  not  all,  of  its  border  at  the 
Illinoian  stage  of  glaciation.  The  lUiuoian  drift  sheet,  as  indicated  in 
detail  farther  on,  passed  some  distance  into  territor}^  which  had  been  occu- 
pied by  the  southern  extension  of  the  Keewatin  ice  sheet  at  the  Kansan  stage. 
Since  the  Illinois  ice  lobe  reached  its  farthest  limits  on  much  of  its  border  at 
the  Illinoian  stage  of  glaciation,  any  earlier  deposit  made  by  this  ice  lobe  must 
be  largely  concealed  by  the  deposits  of  this  stage.  Attention  is  called  below 
to  deposits  in  Illinois  which  may  prove  to  be  sufficiently  older  than  the 
Illinoian  to  be  referable  to  a  distinct  stage,  though  the  evidence  as  yet  is 
rather  fragmentary.  Concerning  this  matter  Professor  Chamberlin  has  sug- 
gested^ that  the  two  great  ice  fields  may  have  alternated  in  their  invasions 
in  such  manner  that  the  sub-Aftonian  preceded  the  sub-Illinoian  and  the 
latter  preceded  the  Kansan,  much  as  the  Kansan  is  known  to  have  preceded 
the  Illinoian.  There  is,  however,  as  yet  no  decisive  e'sddence  of  such  a  rela- 
tionship. Possibly  the  sub-Illinoian  will  prove  to  be  of  about  the  same 
age  as  the  Kansan.  With  these  preliminary  statements  we  pass  at  once  to 
the  discussion  of  the  Illinoian  stag-e  of  glaciation. 

>  Proc.  Iowa  Acad.  Sci.,  Vol.  V,  1898,  pp.  86-101. 
'Communicated  to  the  writer. 


CHAPTER   IV. 

THE  ILLINOIAN  DRIFT  SHEET  AND  ITS  RELATIONS. 

GEN^ERAL  STATEMENT. 

Relation  to  outlying  and  underlying  drift. TllG     fll'St     reCOgnitioil     Rncl     SeparatiOll     of 

the  Illinoian  drift  sheet  from  an  older  sheet  of  drift  which  iinderhes  it  on 
the  borders  of  the  Mississippi  was  made  by  the  writer  in  southeastern  Iowa 
in  the  spring-  of  1894.  The  occurrence  of  a  bowlder  of  red  jaspery  con- 
glomerate in  Lee  County,  Iowa,  had  been  noted  some  ten  years  earlier, 
but  its  significance  was  not  recognized  at  that  time.  It  is  now  found  that 
bowlders  of  this  class  are  not  rare,  and  that  they  are  in  all  probability 
derived  from  the  ledges  north  of  Greorgian  Bay.  If  so,  they  are  an  indica- 
tion that  the  southwestward  movement  of  the  ice  from  that  region  extended 
somewhat  beyond  the  Mississippi  River.  The  studies  in  1894  developed 
other  evidence  that  the  invasion  which  brought  in  these  bowlders  from  the 
northeast  reached  beyond  the  Mississippi,  and  that  it  occurred  at  a  much 
later  date  than  the  general  glaciation  of  southern  Iowa  and  northei'u  Mis- 
souri. The  western  limits  of  this  ice  invasion  are  plainly  indicated  by  a 
marginal  ridge.  The  evidence  of  a  long  interval  is  found  in  the  greater 
erosion  of  the  drift  sheets  outside  the  limits  of  the  Illinoian,  and  in  the 
prevalence  of  a  soil  horizon  and  weathered  zone  beneath  the  Illinoian  sheet 
where  it  overlaps  the  earlier  one.  This  interval  appears  to  be  of  sufficient 
importance  to  be  termed  an  intei'glacial  stage  and  to  justify  the  reference 
of  the  two  sheets  to  distinct  stages  of  glaciation.  The  intervening  stage  of 
deglaciation  has  recently  been  named  the  Yarmouth  interglacial  stage,^  and 
is  discussed  farther  on. 

Relation  to  the  lowan  drift  sheet. — The  qucstiou  ariscs  wliethcr  tlic  lUiuoian  sheet 
should  be  classed  with  the  lowan  sheet,  which,  as  shown  by  McGee  in  the 

'In  a  paper  presented  by  the  writer  at  the  twelfth  annnal  moetiiig  of  tlie  Iowa  Ac.Tdoiuy  of 
Sciences,  December,  1897:  Proo.  Iowa  Acad.  Sci.,  Vol.  A^  1898,  pp.  81-86;  also  Joiiv.  Gcol.,  Vol.  VI,  1898, 
j)p.  238-243. 

2i 


'6. 


C  B 


GENERAL  ASPECTS  OF  ILLINOIAN  DEIFT  SHEET.  25 

Eleventh  Annual  Report  of  this  Survey  and  in  earlier  papers,  is  separated 
from  the  underlying  drift  of  eastern  Iowa  bj^  a  distinct  soil  horizon.  It  is 
found  that  a  notable  interval  occurs  between  the  deposition  of  the  lUinoian 
sheet  of  drift  and  the  deposition  of  the  main  sheet  of  loess  of  the  Mississippi 
Basin,  an  interval  indicated  by  erosion,  weathering,  and  the  formation  of  a 
soil  horizon.  But  this  sheet  of  loess  seems  to  be  intimately  connected  with 
the  lowan  drift  sheet,  as  shown  by  McGree,  a  relation  which  subsequent 
studies  by  several  independent  investigators  fully  confirms.  It  appears, 
therefore,  that  the  Illinoian  drift  sheet  is  separated  by  a  notable  interval  from 
the  lowan  sheet  as  well  as  from  the  underlying  sheets.  Furthermore,  a  till 
sheet  referred  to  the  lowan  stage  is  present  in  northern  Illinois  which  falls 
far  short  of  reaching  the  limits  of  the  Illinoian  till  sheet.  Like  the  lowan 
sheet  of  eastern  Iowa,  it  is  found  to  be  contemporaneous  with  the  main  loess 
deposition.  The  interval  between  the  Illinoian  till  sheet  and  the  lowan 
loess  and  till  has  recently  been  named  the  Sangamon;^  it  is  discussed  in 
some  detail  below.  A  deposit  termed  gumbo,  which  lies  between  the 
Illinoian  till  and  the  lowan  loess,  is  also  described. 

Culmination  of  the  Illinois  lobe  at  the  Illinoian  stage. At  tlie  time  of  tllC  depOsitlOn   of  the 

Illinoian  drift  sheet  the  southwestward  movement  from  Labrador  and  the 
heights  south  of  Hudson  Bay  appears  to  have  reached  a  limit  in  western 
and  southern  Illinois  beyond  any  earlier  invasion.  It  is  not  as  yet  certain, 
though  it  is  quite  probable,  that  the  Illinoian  sheet  extends  beyond  all  older 
sheets  in  northwestern  Illinois  and  southern  Wisconsin.  In  the  absence  of 
positive  evidence  to  the  contrary  the  present  paper  discusses  the  western 
and  southern  limits  of  the  drift  of  the  Illinois  lobe  as  a  single  line,  occupied 
at  the  Illinoian  stage  throughout  its  entire  length  by  the  ice  lobe.  Its 
extent  may  be  seen  by  reference  to  PL  VI. 

GEKERAL  ASPECTS  OF  THE  ILLINOIAN  DRIFT  SHEET. 

Extent  of  its  exposures. — Tlic  Illinoiau  slieet  is  extensively  exposed  to  view 
outside  the  lowan  and  Wisconsin  sheets  in  Illinois  and  southwestern  Indiana. 
In  western  and  southei'n  Illinois  and  in  southwestern  Indiana  it  constitutes 
the  surface  sheet  (aside  from  a  thin  loess  coating)  over  the  entire  interval 
between  the  glacial  boundary  and  the  outer  moraine  of  the  Wisconsin  series. 

'  In  a  paper  presented  by  the  writer  at  the  twelfth  annual  meeting  of  the  Iowa  Academy  of 
Sciences:  Proc.  Iowa  Acad.  Sci.,  Vol.  V,  1898,  pp.  71-80;  also  Jour.  Geol.,  Vol.  VI,  1898,  pp.  171-181. 


26        '  THE  ILLINOIS  GLACIAL  LOBE. 

The  greatest  width  of  this  area  is  about  125  miles,  and  the  width  nowhere 
in  western  or  southern  IlUnois  falls  much  below  75  miles.  In  southwestern 
Indiana  it  occupies  a  triangular-shaped  area,  broad  at  the  west  and  naiTow 
at  the  east,  for  the  glacial  boundary  passes  northward  neai'ly  to  the  edge  of 
the  Wisconsin  drift  in  the  south-central  portion  of  that  State. 

In  the  portion  of  Illinois  north  from  the  latitude  of  Rock  Island  tlie 
lowan  drift  occupies  a  large  part  of  the  interval  between  the  glacial  bound- 
arj^  and  the  outer  moraine  of  the  Wisconsin  series.  A  drift,  tentatively- 
referred  to  the  Illinoian,  forms  the  surface  sheet  in  that  region  in  Stephen- 
son County  and  parts  of  Winnebago,  Ogle,  Whiteside,  Carroll,  and  Jo 
Daviess  counties.  A  small  area  of  this  earlier  drift  in  southwestern  Wis- 
consin is  exposed  outside  the  limits  of  the  lowan,  but  the  exact  boundaries 
of  the  latter  have  not  been  determined. 

If  the  loess  capping  be  disregarded,  nearly  two-thirds  of  the  glaciated 
portion  of  Illinois  has  the  Illinoian  drift  as  a  surface  sheet.  The  remainder 
of  the  State  is  mainly  occupied  hj  the  Wisconsin  drift  sheet,  the  lowan 
being  exposed  only  in  parts  of  a  few  counties. 

Topographic  expression. — Tlie  grcatcr  part  of  the  Illinoian  drift  has  a  plane 
surface,  destitute  of  the  swells  and  ridges  which  usually  occupy  the  Wis- 
consin till  sheet.  There  are,  however,  a  few  belts  of  sharply  ridged  drift 
found  Avithin  its  area,  and  the  border  is  ridged  throughout  much  of  south- 
eastern Iowa  and  western  Illinois.  The  most  conspicuous  ridging  is  found 
in  a  strip  about  20  miles  wide  leading  southwestward  through  the  Kaskaskia 
Basin  from  the  border  of  the  Wisconsin  drift  in  Shelby  County  across 
southeastern  Christian,  eastern  and  southern  Montgomery,  western  Fayette, 
Bond,  Clinton,  southeastern  Madison,  eastern  St.  Clair,  and  eastern  Ran- 
dolph eoimties.  This  strip  embraces  a  series  of  nearly  parallel  ridges,  which 
are  discussed  in  some  detail  farther  on  as  the  ridg&d  drift  of  the  Kaskaskia 
Basin. 

Another  ridged  belt  is  found  in  eastern  Sangamon  and  southwestern 
Loffan  counties,  and  this  is  discussed  below  as  the  Buffalo  Hart  moraine, 
the  village  of  Buffalo  Hart  being  situated  on  it.  A  less  conspicuous  belt  of 
ridged  drift  traverses  southern  and  western  Fulton  County,  touching  eastern 
]iIcDonough  County  near  Bushnell,  and  apparently  having  its  continuance 
into  Knox  and  Peoria  counties  in  a  chain  of  mounds  and  short  ridges.  It 
has  far  less  prominence  than  the  two  belts  just  mentioned,  its  relief  being  but 


GENERAL  ASPECTS  OF  ILLINOIAaST  DEIFT  SHEET.  27 

15  to  30  feet  above  the  bordering  plains,  and  the  breadth  of  the  main  ridge 
one-half  mile,  more  or  less. 

In  the  northwestern  part  of  Illinois,  in  Stephenson,  Ogle,  and  Carroll 
counties,  there  are  gravelly  ridges,  some  of  which  are  of  esker  type,  and 
are  discussed  in  detail  below. 

Aside  from  the  ridged  belts  just  mentioned,  there  have  been  found 
only  occasional  knolls,  either  isolated  or  in  small  clusters,  and  these  seldom 
rise  50  feet  above  the  bordering  plains.  The  knolls  are  more  abundant  in 
western  Illinois  than  in  southeastern  Illinois  and  southwestern  Indiana  In 
the  latter  districts  entire  comities  have  been  traversed  without  the  discovery 
of  a  knoll  so  much  as  10  feet  in  height. 

Thickness  of  the  drift. — The  Well  records  obtained  in  the  region  occupied  by  the 
Illinoian  drift  indicate  that  the  average  distance  to  rock  on  the  preglacial  or 
original  uplands  is  not  far  from  50  feet.  In  this  50  feet  is  included  the  loess, 
which  is  several  feet  in  depth,  and  possibly  also  pre-IUinoian  drift.  Along- 
original  valleys  the  thickness  is  100  to  200  feet  or  more.  There  are  extensive 
areas  in  the  northwestern  counties  of  Illinois  and  in  the  comities  bordering 
the  Wabash  River,  both  in  Illinois  and  in  Indiana,  where  the  ridges  carry 
scarcely  any  drift,  while  neighboring  valleys  may  be  tilled  to  a  depth  of 
100  feet  or  more.  In  western  and  south-central  Illinois  the  ridges  usually 
carry  30  to  50  feet  of  drift,  the  general  amount  of  drift  being  gi-eater  than 
in  northwestern  Illinois  or  southeastern  Illinois  and  southwestern  Indiana. 
Throughout  the  area  occupied  by  the  Illinoian  drift  the  main  preglacial 
valleys  are  usually  but  partiallj^  concealed,  though  the  small  valleys  and 
tributaries  are  often  filled  so  completely  that  their  position  is  revealed  only 
by  borings.  In  this  resjiect  the  Illinoian  drift  is  in  striking  contrast  with 
the  Wisconsin,  for  where  that  sheet  is  present  the  main  valleys  are  as  com- 
pletely concealed  as  the  lesser  ones. 

Records  of  a  large  number  of  wells  which  have  been  sunk  in  the 
Illinoian  drift  area  are  presented  in  the  portion  of  this  report  dealing  with 
the  wells  (Chapter  XIV). 

Structure  of  the  drift. — Tlirougliout  tlie  area  occupied  by  the  Illinoian  drift 
till  predominates,  there  being  but  a  small  amount  of  sand  or  gravel  except 
in  deeply  tilled  valleys.  The  ridges  above  mentioned  are  usually  com- 
posed of  till,  though  pockets  or  thin  beds  of  sand  or  g-ravel  have  been 
discovered  in  some  of  them.     Upon  passing  toward  the  glacial  boundaiy 


28  THE  ILLINOIS  GLACIAL  LOBE. 

the  drift  becomes  more  variable  in  its  constitution  than  at  points  remote 
from  the  boundary.  This  variableness  is  set  forth  in  the  detaikd  discussion 
of  the  drift  border  below. 

The  till  whicli  forms  this  lllinoian  sheet  is  usually  of  a  yellowish-brown 
color  to  a  depth  of  15  feet  or  more,  beneath  whicli  it  assumes  a  gray  or 
blue-gray  color.  In  many  places  there  is  a  transition  from  the  brown  to 
the  gray,  in  which  gray  streaks  remain  in  the  brown  till,  or  cracks  stained 
a  brown  color  extend  down  some  distance  into  the  gray  till.  In  such  places 
it  is  probable  that  the  brown  is  simply  an  altered  gray  till,  the  oxidation  of 
the  iron  having  produced  the  change  in  color.  In  places  a  thin  bed  of  sand 
or  gravel  occurs  at  the  junction  of  the  brown  and  gray  till,  which  gives 
them  the  appearance  of  being  originally  distinct.  But  it  is  not  certain  that 
the  brown  till  in  such  places  was  not  originally  gray  in  color.  The  points 
at  which  there  is  a  transition  from  till  of  one  color  to  that  of  the  other  are  so 
numerous  that  it  seems  highly  probable  that  the  brown  till  is  generally  but 
an  altered  phase  of  the  gray.  At  least  nothing  decisive  has  been  discovered 
to  indicate  that  the  brown  and  gray  tills  are  referable  to  distinct  invasions 
or  to  different  modes  of  deposition  by  the  ica 

In  portions  of  central  Illinois,  especially  in  the  Sangamon  and  Kaskaskia 
and  Embarras  drainage  basins,  the  well  diggers  and  di'illers  report  a  marked 
change  in  the  texture  of  the  drift  in  passing  from  the  brown  to  the  gray 
■tills.  The  gray  till  is  said  to  be  much  harder  to  penetrate  than  the  broM'u. 
Where  wells  are  dug,  they  may  be  spaded  without  difficulty  through  the 
brown  till,  while  in  the  gray  till  a  pick  is  usually  required  to  remove  the 
material.  This  difference  may  be  due  to  the  effect  of  ground  water  or  to 
some  secondary  change  in  the  brown  till  which  does  not  affect  the  underly- 
ing gra}^  till,  a  change  which  is  coextensive  with  the  change  in  color.  It 
may,  however,  prove  to  be  an  original  difference  and  may  be  of  significance 
in  determining  the  glacial  history.  Possibly  the  gray  till  in  these  districts 
is  sufficiently  older  than  the  overlying  brown  till,  or  sufficiently  distinct  from 
it  in  deposition,  to  be  referred  to  a  separate  stage  and  c'(iusidered  pre-Illi- 
noian.  But  few  exposures  of  this  hard  till  were  found,  and  in  these  no  sign 
of  a  distinct  interval  between  tlie  bro^vn  and  the  gray  tills  was  recognized. 
The  available  evidence  is,  therefore,  of  an  inconclusive  nature. 

Gumbo  (?i. — The  lllinoian  till  sheet,  and  also  portions  of  the  Kansan  till 
sheet  in  southeastern  Iowa  and  northern  Missouri,  ai-e  extensively  covered 


GENERAL  ASPECTS  OF  ILLINOIAN  DEIFT  SHEET.  29 

with  a  gummy  or  very  adhesive  clay,  often  several  feet  in  depth.  This 
clay  is  found  at  frequent  intervals  throughout  the  entire  area  in  which  the 
Illinoian  sheet  is  exposed  to  view  outside  the  limits  of  later  till  sheets, 
and  has  also  been  found  under  the  later  till  sheets  at  some  distance 
back  from  their  margin  in  the  central  portion  of  Illinois.  It  occurs  as  far 
west  as  the  writer  has  made  examinations  in  Iowa,  a  distance  of  50 
miles  or  more  beyond  the  limits  of  the  Illinoian  till  sheet,  and  is  known 
to  be  present  over  extensive  areas  in  northern  Missouri.  Its  extent  and  im- 
portance seem  to  have  been  unrecognized  prior  to  the  present  survey.  It  is 
not  such  a  continuous  deposit  as  the  overlying  loess,  there  being-  many 
places  Avhere  the  loess  rests  directly  upon  typical  till.  It  is  most  conspicu- 
ous in  the  vicinity  of  the  Mississippi  Valley  and  in  the  southern  portion  of 
Illinois  as  far  south  as  the  glacial  boundary.  The  region  in  which  it  occurs 
ranges  in  elevation  from  400  feet  up  to  fully  800  feet  above  tide.  Possibly 
much  higher  elevations  are  attained  by  it  in  passing  westward  from  the 
Mississippi.  Like  the  loess,  it  seems  to  be  independent  of  contour  lines  in 
its  distribution. 

The  color  of  this  clay  varies  from  ash  or  light  gray  to  nearly  black. 
The  black  portions  are  heavily  charged  with  liumus  and  in  places  present 
the  appearance  of  a  swamp  muck.  It  is  in  this  clay  that  the  black  soil  so 
often  seen  at  the  base  of  the  loess  is  usually  developed.  Where  the  loess 
rests  directly  upon  till  the  soil  formed  beneath  it  is  usually  of  a  reddish- 
brown  color. 

This  gummy  clay  contains  a  few  small  pebbles.  They  seldom  exceed 
a  half  inch  in  diameter  and  are  far  less  numerous  than  in  the  typical  till. 
It  often  bears  a  striking  resemblance  to  the  "gumbo"  of  the  Illinois  and 
Mississippi  River  flood  plains,  which  is  deposited  by  flooded  streams  in  the 
portions  of  the  flood  plains  where  there  is  but  little  current.  It,  however, 
contains  more  and  larger  pebbles  than  the  gumbo  of  these  flood  plains. 

The  origin  of  this  deposit,"  and  its  time  relations  compared  with  the 
overlying  loess  and  the  underlying  till,  are  questions  of  prime  importance, 
but  as  yet  no  satisfactory  conclusions  have  been  reached.  There  is  much 
in  the  appearance  of  the  deposit  to  support  the  hypothesis  of  aqueous 
deposition.  The  pebbles  may,  perhaps,  have  been  derived  from  neighbor- 
ing prominent  points  in  the  till  during  the  progress  of  a  submergence.  The 
action  of  floating  ice  may  be  postulated  as  an  accompaniment  of  submergence 


30  THE  ILLINOIS  GLACIAL  LOBE. 

■whether  the  water  be  shallow  or  deep,  and  this  may  have  caiTied  stones  in 
sufficient  number  to  have  supplied  the  clay  with  the  iew  pebbles  that  it 
contains.  The  difficulties  arising-  from  the  great  range  in  altitude  which 
the  deposit  presents  may  not  be  fatal  to  the  hypothesis  of  submergence. 
The  hypothesis  is,  therefore,  still  entertained,  especially  since  none  more 
satisfactory  has  suggested  itself,  but  it  can  not  be  confidently  put  forward 
as  a  solution. 

In  considering  the  time  relations  of  this  clay,  there  is  decisive  evidence 
that  it  was  deposited  at  a  much  later  date  than  the  Kansan  sheet,  in  the 
fact  that  it  also  overlies  the  Illinoian,  a  younger  sheet  of  drift.  The 
evidence  is  equal!}'  conclusive  from  its  relation  to  terraces  cut  in  the 
Kansan.  The  gummy  clay,  as  well  as  its  coating  of  loess,  is  found  on 
ten-aces  bordering  valleys  cut  in  the  Kansan  sheet,  and  also  on  the  uplands 
occupied  by  that  sheet.  All  the  main  valleys  examined  in  southeastern 
Iowa  had  been  cut  to  a  depth  of  50  feet  or  more  into  the  Kansan  sheet, 
and  often  to  a  width  of  1  or  2  miles,  prior  to  the  deposition  of  this  clay. 
If,  therefore,  it  had  been  examined  onl}-  in  districts  outside  the  limits  of 
the  Illinoian,  it  might  have  been  demonstrated  to  be  a  much  younger  deposit 
than  the  Kansan. 

Passing  to  the  Illinoian  sheet,  it  is  found  that  the  changes  effected  in 
its  surface  prior  to  the  deposition  of  the  cla}-  under  discussion  are  less  than 
in  the  Kansan,  yet  some  change  was  apparently  effected  in  its  surface.  In 
fact,  the  surface  of  the  till  has  often  the  appearance  of  marked  atmospheric 
reddening  prior  to  the  deposition  of  the  gummy  clay,  and  there  is  usually 
iin  abrupt  chaiige  from  gummy  clay  to  the  till.  The  till  is  also  not  infre- 
quently leached  of  its  calcareous  material  for  several  feet  below  the  base 
of  the  gummy  clay.  In  places  the  gummy  clay  is  mingled  with  the  luider- 
lying  till,  but  it  does  not  follow  that  the  two  deposits  are  contemporaneous. 
The  Illinoian  till  sheet  was  not  so  conspicuously  channeled  by  streams 
prior  to  tlie  loess  deposition  as  the  neighboring  portion  of  the  Kansan,  but 
the  slight  channeling  which  took  place  seems  to  have  antedated  the  deposi- 
tion of  the  gummy  clay  as  well  as  that  of  the  ove^'lying  loess.  This  clay 
is  apparently  more  conspicuously  developed  in  small  channels  cut  in  the 
Illinoian  than  on  the  bottosns  or  terraces  of  the  broad  channels.  Not  infre- 
(|uently  these  small  channels  are  so  greatly  filled  by  the  clay  that  the 
surface  is  nearly  restored  to  its  original  pl^ineuess.     The  writer  has  found 


GENERAL  ASPECTS  OF  TLLmOIAN  DRIFT  SHEET.  31 

numerous  exposures  where  such  filhng-  reaches  a  depth  of  15  or  20  feet  in 
districts  where  the  general  thickness  of  the  gummy  clay  is  scarcely  5  feet. 
The  presence  of  so  many  exposures  where  there  is  evidence  of  an  interval 
between  the  deposition  of  the  till  and  tliat  of  the  clay  under  discussion  has 
led  the  writer  to  conclude  that  in  the  exposures  where  the  two  deposits 
appear  to  be  blended  there  has  been  redeposition  of  the  till  in  connection 
with  the  later  deposit.  In  so  commingled  a  sheet  as  till  it  is  a  very  difficult 
matter  to  determine  whether  redeposition  has  occurred  since  the  withdrawal 
of  the  ice  sheet.  In  view  of  all  the  data  now  available  the  conclusion 
seems  warranted  that  this  clay  is  somewhat  younger  than  the  Illinoian. 

No  suitable  name  has  as  yet  been  found  for  the  clay,  although  the 
name  gumbo  has  been  applied  to  it  by  residents  of  the  region  which  it  char- 
acterizes, becaiise  of  its  gummy  character.  This  name  is  open  to  objec- 
tion for  the  reason  that  it  has  already  been  applied  to  other  deposits  of 
different  age  and  different  origin.  There  is  a  gumbo  in  the  Cretaceous 
series  of  the  Western  plains.  The  term  is  also  applied  to  the  flood-plain 
deposits  of  the  Illinois  and  Mississippi,  which  are  still  in  process  ot  accumu- 
lation. The  name  gumbo  has,  however,  been  used  b}''  McGree  in  his  discus- 
sion of  a  compact  phase  of  the  loess  found  in  southeastern  Iowa  and 
northern  Missouri,  and  of  a  dark  clay  at  its  base,  apparently  the  clay  under 
discussion.  It  is  his  opinion  that  the  loess  there  owes  its  compactness  to 
derivation  from  the  clay  beneath  it.^  Until  the  origin  and  time  relations 
are  more  satisfactorily  determined,  it  may  be  as  well  to  leave  unsettled  the 
name  for  the  deposit. 

It  remains  to  consider  the  probable  time  relations  between  the  clay 
under  discussion  and  the  sheet  of  loess  that  overlies  it.  The  gummy  clay, 
as  noted  above,  has  usually  a  blackened  surface  due  to  humus,  a  feature 
which  indicates  that  it  was  exposed  to  conditions  favorable  to  plant  growth. 
The  plant  remains  in  this  clay  are  seldom  sufficiently  well  preserved  to 
admit  of  identification.  The  writer.  howeA'er,  found  bits  of  wood  in  an 
exposui'e  along  the  Santa  Fe  Railway  near  New  Boston,  in  Lee  County, 
Iowa,  which  have  been  identified  by  Mr.  F.  H.  Knowlton,  of  the  United 
States  National  Museum,  as  a  species  of  conifer.  The  specimens  were  too 
small  and  not  sufficiently  well  preserved  to  enable  him  to  determine  the 
genus  and  species,  though  they  appear  to  belong  to  the  genus  Picea  (spruce). 

'Eleventh  Aun.  Kept.  U.  S.  Geol.  Survey  (for  1889-90),  1891,  pp.  299,  414,  461-471,  508-51U. 


32  THE  ILLINOIS  GLACIAL  LOBE. 

They  consist  of  rootlets  about  2  cm.  in  length  and  2  mm.  in  diameter. 
They  are,  therefore,  too  small  to  afford  good  sections  of  the  wood  cells. 
The  locality  where  these  specimens  were  obtained  is  now  a  prairie  region 
and  the  spruce  tree  is  not  native  in  the  forests  which  border  the  streams, 
the  only  conifer  present  being  the  red  cedar.  Several  instances  of  the 
occurrence  of  logs  at  the  base  of  the  loess  in  western  Illinois  have  been 
reported  to  the  writer  by  well  drillers,  but  no  specimens  have  been  obtained. 
The  evidence  is,  however,  considered  good  that  much  of  this  region  was 
forest-covered  prior  to  the  deposition  of  the  loess.  Whether  this  emergence 
and  forest  growth  occupied  a  long  period  has  not  been  satisfactorily  deter- 
mined.   . 

Last  season  (1897)  the  writer  found  a  fine  exposure  of  muck  and  peat 
and  wood,  associated  with  silt,  at  the  base  of  the  loess  in  a  cutting  on  the 
Toledo,  Peoria  and  Western  Railway,  4  miles  west  of  Washington,  Illinois,  a 
photograph  of  which  is  presented  in  PI.  XI,  B.  It  is  several  miles  inside 
the  border  of  the  Wisconsin  drift,  and  the  loess  is  here  covered  by  a  bed  of 
till  of  Wiscoiisin  age.  At  this  cutting  the  Wisconsin  drift  is  only  15  feet  in 
thickness,  the  upper  portion  having  been  removed  by  erosion.  The  section 
at  the  cutting  is  as  follows: 

Section  at  a  cutting  on  the  Toledo,  Peoria  and  Western  Railway,  4  miles  west  of  Wash- 
ington, Illinois. 

Feet. 

Gravel 6 

Blue  till  ( Wisconsin) 8 

Gray  clay,  laminated,  pebbleless,  very  calcareous 1 

Brown  loess,  probably  of  lowan  age,  calcareous,  and  containing  helix  shells 6 

Pea^y  silt  of  brownish  black  color,  containing  a  large  amount  of  wood  (Sangamon) 5 

Drab  colored  loess-liku  silt,  becoming  brown  toward  bottom,  filled  with  mats  of  librous  roots. .  1-5 

Reddish-brown  leached  till  (IlUnoian) 4 

Brown  nnleached  till  (Illinoian)  exposed 8 

Total 42 

Specimens  of  the  shells  in  the  loess,  of  the  wood  in  the  peat,  and  of  the 
roots  tinder  the  peat  have  been  collected,  but  have  not  been  specifically 
identified.  The  silt  under  the  peat  is  somewhat  similar  to  the  deposit  which 
overlies  it,  thougli  it  may  prove  to  be  of  different  origin.  This  series  of 
beds  seems  to  indicate  that  a  land  surface,  which  had  been  exposed  to 
atmospheric  action  favorable  for  leaching  of  the  till,  was  transformed  into 
a  swamp  favorable  to  tlie  growth  of  peat,  and  that  this  swampy  condition 
was  followed  by  the  deposition  of  the  loess.     As  the  gummy  clay  just  dis- 


GENERAL  ASPECTS  OF  ILLINOIAN  DRIFT  SHEET.  33 

cussed  is  not  represented  in  this  section,  the  question  naturally  ai'ises  whether 
the  silty  material  under  the  peat  is  not  its  equivalent.  The  question  can 
scarcely  be  decided  from  such  fragmentary  evidence  as  is  now  available. 
This  section  appears  to  bring-  the  loess  into  closer  relation  to  the  gummy 
clay  than  had  heretofore  been  supposed.  If  the  blackened,  humus-stained 
surface  of  the  gummy  clay  required  but  a  few  centui'ies  for  its  development, 
it  would  seem  not  unlikely  that  the  deposition  of  this  gummy  clay  and  tliat 
of  the  loess  are  to  be  referred  to  the  same  epoch  of  low  altitude,  an  epoch 
attended  by  more  or  less  complete  submergence,  with  interruptions  or  partial 
emergence  of  the  land.  The  reddened  and  leached  surface  of  the  lUinoian 
till  apparently  signifies  a  long  exposure  to  atmospheric  action.  The  balance 
of  evidence  seems  to  favor  a  closer  connection  between  the  loess  and  the 
gummy  clay  than  between  the  latter  and  the  underlying  lUinoian  till. 

As  the  loess  is  discussed  in  some  detail  in  connection  with  the  lowan 
drift  sheet,  with  which  it  is  correlated,  only  a  general  statement  concerning' 
it  is  made  at  this  point.  The  entire  surface  of  the  Illinoian  drift  sheet 
appears  to  have  received  a  capping  of  loess  or  loess-like  silt  at  about  the 
time  of  the  lowan  ice  invasion,  the  deposit  being  found  midway  between 
the  principal  streams  as  well  as  along  their  borders,  where  it  was  first 
recognized.  It  is  much  thicker  on  the  borders  of  the  Illinois  and  Missis- 
sippi than  on  the  divide  between  these  streams  or  in  the  region  east  from 
the  Illinois.  In  much  of  southern  Illinois  the  thickness  is  only  3  to  5  feet, 
and  the  average  thickness  in  districts  east  of  the  Illinois  and  Mississippi  is 
probably  less  than  10  feet.  On  the  borders  of  these  streams  its  thickness 
is  frequently  30  to  50  feet,  though  a  portion  of  the  valley  border  near  the 
corners  of  Iowa,  Missouri,  and  Illinois  is  characterized  by  a  thinner  coating 
of  loess  than  is  found  to  the  north  or  south,  the  average  thickness  being 
scarcely  10  feet.  Aside  from  its  thickening  on  the  borders  of  the  Illinois  and 
Mississippi,  there  is  also  a  thickening-  on  the  borders  of  the  lowan  drift  sheet 
in  Carroll,  Whiteside,  Henry,  and  Bureau  counties,  as  indicated  in  the 
discussion  of  that  drift  sheet. 

Sections  of  the  Illinoian  drift. — For  scctlous  iUustratiug'  thc  structurc  of  the 
Illinoian  drift  sheet,  reference  may  be  made  to  the  portion  of  this  report 
devoted  to  the  wells  of  Illinois  (Chapter  XIV).  The  well  sections  are  taken 
up  by  counties,  but  attention  is  called  to  the  several  drift  sheets  which  are 

MON  XXXVIII 3 


34  THE  ILLINOIS  GLACIAL  LOBE. 

penetrated  by  the  wells  in  the  various  counties  of  the  State.  The  structure 
of  the  portion  of  the  Illinoian  drift  in  southeastern  Iowa  and  western  Illinois 
is  set  forth  in  the  detailed  discussion  of  the  border  of  the  Illinoian  drift  sheet 
which  follows. 

THE   DRIFT  BORDER. 

DISTRIBUTION. 

The  border  of  an  old  drift  sheet,  tentatively  referred  to  the  Illinoian, 
emerges  from  beneath  the  Wisconsin  di'ift  in  southern  Wisconsin  a  few 
miles  southwest  of  the  city  of  Madison,  and  from  that  point  southward  to 
the  Mississippi  River  it  forms  the  eastern  border  of  the  Driftless  Area  of 
southwestern  Wisconsin  and  northwestern  Illinois.  The  border  of  this  drift 
sheet  probably  crosses  the  Mississippi  a  few  miles  below  Savanna,  but,  as 
shown  in  Pis.  VI  and  XII,  the  presence  of  the  lowan  drift  sheet,  together 
with  the  heavy  loess  deposit,  both  of  which  are  later  than  this  drift,  has 
so  obscured  it  that  its  limits  can  not  well  be  determined  in  Clinton  and 
Scott  counties,  Iowa.  In  Muscatine  County,  Iowa,  the  slightly  ridged  west- 
ern border  of  the  Illinoian  drift  sheet  becomes  visible,  and  is  distinctly  devel- 
oped from  that  county  southward.  It  crosses  the  Iowa  River  just  below 
Columbus  Junction  and  leads  southward  through  western  Louisa  County,  the 
village  of  Cairo  being  within  a  mile  and  the  village  of  Morning  Sun  within 
3  or  4  miles  east  of  the  border.  It  passes  thence  in  a  course  west  of  south 
across  northwestern  Des  Moines  County  and  southeastern  Henry  County,  tlie 
villages  of  Yarmouth  and  New  London  being  situated  on  the  ridged  border 
and  the  village  of  Lowell,  in  Skunk  River  Valley,  being  situated  where  the 
border  crosses  that  valley.  In  Lee  County,  as  shown  in  fig.  4,  the  course  of 
the  ridge  is  southward  past  the  village  of  West  Point  to  the  vicinity  of  the 
Mississippi  bluff,  about  5  miles  below  Fort  Madison.  From  this  point  south- 
ward to  Keokuk  the  border  apparently  is  nearly  coincident  with  the  course  of 
the  Mississippi  River,  though  there  may  be  slight  deposits  of  the  Illinoian 
drift  on  the  west  side  of  the  valley.  Immediately  south  of  Keokuk,  on  the 
Illinois  side  of  the  river,  a  distinct  ridge  of  drift  appears  which  marks  the 
border;  and  this  may  be  traced  southward  along  the  east  bluff  of  the  Mis- 
sissippi across  Hancock  and  Adams  counties,  though  in  the  southern  portion 
of  Adams  County  it  lies  back  a  mile  or  two  east  from  the  river  bluft'.  In 
Pike  County  the  border  bears  gradually  away  from  the  Mississijjpl  bluff  in 


THE  DRIFT  BOEDER.  35 

a  southeastward  course  and  comes  to  the  Illinois  River  in  the  southeast  part 
ot"  the  county;  thence  it  follows  the  Illinois  Valley  southward  to  the  mouth 
of  the  river,  perhaps  touching  the  west  bluff  in  southern  Calhoun  County. 
The  border  then  either  follows  the  Mississippi  bluff  eastward  past  Alton,  or 
continues  southward  across  the  projecting  point  of  Missouri  which  borders 
the  mouth  of  the  Missouri  River  just  above  St.  Louis.  It  is  somewhat 
uncertain  whether  the  drift  found  on  the  Missouri  side  of  the  Mississippi  is 
of  direct  glacial  deposition  or  a  deposit  made  by  streams;  the  greater  part 
of  it  is  assorted  material.  The  presence  of  drift  on  the  Missouri  side  of  the 
Mississippi  has  been  noted  only  in  the  district  north  from  the  citv  of  St. 
Louis.  Below  that  city  the  drift  border  apparently  follows  the  line  of  the 
valley  of  the  Mississippi  closely  as  far  down  as  southern  Jackson  County. 
The  Mississippi  River  there  turns  southward,  but  the  drift  border  passes 
eastward,  following  the  north  slope  of  the  elevated  ridge  which  crosses  south- 
ern Illinois  and  entering  Indiana  in  the  extreme  southwest  corner  of  that 
State. 

The  drift  border,  as  indicated  on  PI.  VIII,  crosses  the  southwestern 
county  of  Indiana  (Posey)  in  a  northeastward  course  lying  near  the  valley 
of  the  north  fork  of  Big  Creek.  It  cuts  across  the  nort,hwest  corner  of 
Vanderburg  County  and  enters  Gibson  County  in  sec.  16,  T.  4  S.,  R.  11  W. 
Thence  it  passes  northeastward,  touching  the  village  of  Haubstadt  and 
coming  to  Pigeon  Creek  in  sec.  22,  T.  3  S.,  R.  10  W.,  at  the  junction  of  Sand 
Fork  and  i\Iuddy  Fork.  From  this  creek  the  course  for  a  few  miles  is 
northward  to  the  divide  between  Pigeon  Creek  and  Patoka  River,  which  it 
crosses  about  4  miles  east  of  Princeton.  It  there  swings  eastward  and 
comes  to  Patoka  River  near  the  line  of  sees.  32  and  33,  T.  1  S.,  R.  9  W. 
It  enters  Pike  County  about  1  mile  south  of  Oatsville,  in  sec.  27,  T.  1  S., 
R.  9  W.  In  that  county  it  lies  but  a  short  distance  north  of  Patoka  River, 
and  apparently  follows  nearly  the  divide  between  the  small  northern  tributa- 
ries and  Flat  Creek,  a  large  northern  tributary,  to  the  mouth  of  Flat  Creek 
in  western  Dubois  County.  From  this  point  eastward  to  the  vicinity  of 
Jasper,  and  thence  northward  to  East  White  River,  there  is  a  sand-covered 
plain  in  which  the  boundary  is  difficult  to  locate.  Possibly  this  plain  was 
covered  by  the  ice  sheet,  since  glacial  pebbles  several  inches  in  diameter 
are  found  beneath  the  sand  on  its  east  border.  The  sand  seems  to  have 
been  deposited  in  a  small  glacial  lake,  Lake  Patoka,  which  occupied  this 


36  THE  ILLINOIS  GLACIAL  LOBE. 

plain  and  neighboring  sections  of  the  Patoka  Valley  while  the  ])resent  out- 
lets along  the  White  and  Wabash  rivers  were  blocked  by  the  ice  sheet. 

For  a  few  miles  north  from  East  White  River  the  exact  position  of  the 
glacial  boundary  is  difficult  to  locate,  for  only  scattering  pebbles  are  foiuid 
along  the  border.  It  seems,  however,  to  pass  near  the  village  of  Alfords- 
ville,  in  Daviess  County,  and  thence  to  take  a  northeastward  course  to  the 
Ijluff  of  East  White  River  near  Whitfield,  in  Martin  County.  The  border 
follows  the  west  blufiP  of  East  White  River  northward  past  Mount  Pleasant 
to  the  bend  near  that  village,  from  Avhich  point  it  continues  northward, 
passing  about  a  mile  east  of  the  village  of  Loogootee.  The  border  then 
bears  west  of  north  and  soon  enters  the  western  range  of  sections  in  I\Iartin 
County  and  lies  very  near  the  Martin-Daviess  county  line  for  10  or  12  miles. 
It  makes  a  slight  protrusion  eastward  at  the  valley  of  Furse  Creek,  in 
northwestern  Martin  County,  and  enters  Greene  Count}^  about  a  mile  south- 
east of  the  village  of  Scotland. 

The  course  of  the  glacial  boundary  through  Greene,  Owen,  and  Mon- 
roe counties  has  been  mapped  in  detail  by  Mr.  C.  E.  Siebenthal,  of  the 
Indiana  Geological  Survey,  and  is  represented  in  PI.  IX.  From  near 
Scotland  it  has  a  course  slightly  east  of  north  to  the  valley  of  Plummer's 
Creek,  in  sec.  9,  T.  6  N.,  R.  4  W.  North  of  this  creek  it  makes  an  east- 
ward protrusion  of  about  2  miles  into  a  lowland  tract  known  as  the  Ameri- 
can Bottom,  reaching  sec.  36,  T.  7  N.,  R.  4  W.  North  of  this  lowland  the 
course  of  the  boundary  is  west  of  north  to  the  valley  of  Richland  Creek, 
in  sec.  9,  T.  7  N.,  R.  4  W.  It  follows  the  east  bluff  for  about  3  miles  and 
crosses  to  the  west  side  of  the  creek  in  sec.  35,  T.  8  N.,  R.  4  W.  It  follows 
nearly  the  west  bluff  to  sec.  17,  T.  8  N.,  R.  3  W.,  passing  about  a  mile 
southeast  of  the  village  of  Newark.  The  boundary  makes  an  eastward 
protrusion  of  about  a  mile  into  Richland  Creek  Valley  in  sec.  16,  from 
which  the  course  is  northward  into  Owen  County.  Entering  Owen  County 
in  sec.  33,  T.  9  N.,  R.  3  W.,  the  boundary  leads  northeastward  past  Free- 
man post-office  and  crosses  into  Monroe  County  in  sec.  6,  T.  i)  N.,  R.  2  W. 
The  course  continues  northeastward  through  northern  Monroe  County,  the 
boundary  being  about  2  miles  north  of  Ellettsville  and  1  mile  north  of 
Modesto,  and  coinciding  nearly  with  Indian  Creek  Valley  from  mouth  to 
source.  From  the  head  waters  of  Indian  Creek,  in  sec.  3,  T.  10  N.,  R.  1  W., 
the    boundary  leads  eastward    about  6   miles,  near    the    Monroe-Morgan 


THE  DRIFT  BOEDER.  37 

county  line,  and.  there  reaches  its  most  northern  point  in  Indiana.  It  is 
here  that  the  hmits  of  the  portion  of  the  ice  sheet  properly  included,  in  the 
Illinois  glacial  lobe  should  be  placed.  The  boundary  from  there  leads 
southeastward  to  the  Ohio  Vallej^,  and  is  discussed  in  another  report  in 
preparation.  The  drift  border  shows  no  evidence  of  an  overlapping  at 
this  reentrant  angle  of  one  lobe  upon  territory  abandoned  by  the  other, 
such  as  was  noted  on  the  west  side  of  the  Illinois  lobe.  The  border  south- 
east from  the  reentrant  seems  to  be  a  direct  continuation  of  that  just  traced. 

The  length  of  the  drift  border  thus  outlined  is  about  700  miles,  and  the 
width  of  the  lobe  encircled  by  it  is  about  300  miles.  The  tracing  of  this 
border  has  been  the  product  of  several  independent  surveys.  The  portion 
in  Wisconsin  was  largely  determined  by  members  of  the  Wisconsin  Geo- 
logical Survey.  The  border  in  northwestern  Illinois  was  partly  determined 
by  members  of  the  Illinois  Greological  Survey,  and  subsequently  with  greater 
approximation  by  Prof.  R.  D.  Salisbury,  of  the  United  States  Greological 
Survey,  but  the  precise  limits  have  not  as  yet  been  mapped.  The  portion 
in  Iowa,  and  also  the  portion  from  the  southern  edge  of  Iowa  southward  to 
the  vicinity  of  St.  Louis,  have  been  traced  by  tlio  present  writer.  Salis- 
bury, however,  made  observations  at  an  earlier  date  on  the  limits  of  the 
drift  in  Pike  and  Calhoun  counties,  Illinois,  and  discovered  evidence  suo-- 
gesting  that  a  portion  of  these  counties  is  unglaciated.  The  deposits  of 
drift  on  the  Missouri  side  of  the  Mississippi,  in  the  vicinity  of  St.  Louis, 
were  first  described  by  Prof  A.  H.  Worthen^  and  later  by  Profs.  G.  F. 
Wright,'  J.  E.  Todd,^  and  H.  A.  Wheeler.*  The  portion  of  the  boundary 
from  St.  Louis  southward  to  Jackson  County,  Illinois,  was  mapped  by  Prof 
G.  F.  Wright  and  discussed  in  Bulletin  58  of  this  Survey.  Wright  also 
mapped  the  boundary  across  southern  Illinois,  but  this  had  previously  been 
outlined  with  a  fair  degree  of  approximation  bj-  Worthen.^ 

Wright  also  made  a  tracing  of  the  glacial  boundary  in  southwestern 
Indiana,  which  was  published  in  Bulletin  58  of  this  Survey.  But  the  posi- 
tion of  the  boundary  in  that  region  is  found  to  be  shown  very  inaccurately, 
the  limits  of  the  drift  being  from  5  to  20  miles  outside  the  hmits  placed  by 


'  Geol.  of  Illinois,  Vol.  1, 1866,  p.  314. 

2  Bull.  U.  S.  Geol.  Survey,  No.  58,  pp.  72-73. 

=  Bull.  Geol.  Soc.  America,  Vol.  V,  1894,  p.  539.     Missouri  Geol.  Survey,  Vol.  X,  1896,  pp.  161-163. 

^ Trans.  St.  Louis  Acad.  Sci.,  Vol.  VII,  No.  3,  Feb.,  1895. 

^Geol.  of  Illinois,  Vol.  1, 1866,  p.  27. 


38  THE  ILLmOIS  GLACIAL  LOBE. 

Wright.  As  indicated  above,  its  position  in  Monroe,  Owen,  and  Greene 
counties  lias  been  mapped  in  detail  by  Mr.  C.  E.  Siebenthal,  of  the  Indiana 
Survev.  The  portion  l^etween  Greene  County  and  the  southwest  corner  of 
Indiana  has  been  traced  by  the  present  writer.  The  portion  mapped  by 
Siebenthal  has  been  reconnoitpred  by  the  present  writer,  and  also  most  of 
the  border  in  southern  and  southwestern  Illinois. 

TOPOGRAPHIC    EXPRESSION. 

The  drift  border  in  the  portion  examined  by  the  writer,  both  in  south- 
eastern Iowa  and  in  western  Illinois,  is  generalh*  marked  b}^  a  low  ridge, 
seldom  rising  more  than  60  feet  above  the  outer  border  disti-ict,  and 
averaging  perhaps  40  feet.  In  Adams  and  Pike  counties  there  are  a  series 
of  ridges  shown  on  the  glacial  map  (PI.  VI),  which  have  neai-ly  parallel 
trend,  but  which  are  broken  by  wide  gaps,  and  represent  imperfectly  the 
successive  positions  of  the  ice  margin  in  these  counties.  The  ridge  forming 
the  border  seldom  exceeds  2  miles,  and  is  usually  but  a  mile  or  less  in  width. 
On  the  eastern  slope  there  are  low  swells,  10  to  20  feet  in  height,  extend- 
ing out  in  places  to  a  distance  of  several  miles  from  the  drift  border,  but 
seldom  showing  a  disposition  to  form  connected  chains  or  ridges. 

The  portion  of  the  drift  border  along  the  east  side  of  the  Driftless 
Ai-ea  in  northern  Illinois  and  southern  Wisconsin  is  in  places  slightly  thick- 
ened beyond  the  usual  depth  of  di'ift  in  districts  to  the  east,  but  is  in  other 
places  very  thin.  It  may  be  possible  to  trace  an  ill-defined  ridging  more 
or  less  successfully  near  this  border.  The  writer's  observations  touch  it  at 
only  a  few  points,  and  are  not  sufficiently  full  or  continuous  to  justify  an 
opinion  on  this  matter. 

From  the  point  where  the  border  crosses  the  Illinois  River  in  south- 
eastern Pike  County,  Illinois,  southward  to  the  Mississippi,  there  are  occa- 
sional knolls,  20  to  40  and  occasionally  60  feet  in  height,  the  majorit}'  of 
whicli  are  elliptical,  with  tlie  longer  axis  trending  ENE.-WSW.,  or  about 
at  right  angles  to  the  trend  of  the  drift  border.  These  knolls  do  not  lie  at 
the  extreme  border,  but  are  situated  5  to  10  miles  or  more  liack  from  it. 
Their  form  is  drumlinoid,  but  seldom  assumes  the  regularity  of  the  typical 
drumlin. 

The  portion  of  the  drift  border  touching  the  State  of  Missoui-i  displays 
(ihIa-  ]);itchy  deposits  of  drift,  usually  in   t]\v  valleys  or  depressions,  and 


TOPOGRAPHIC  EXPEESSION  OF  THE  DRIFT  BORDER.  39 

seldom,  if  ever,  aggregated  in  the  form  of  knolls  or  ridges.  As  noted  above, 
it  is  not  certain  but  that  the  deposition  was  largely  made  by  streams,  rather 
than  by  direct  glacial  action. 

Below  St.  Louis  there  is  a  less  regular  and  lighter  deposit  of  drift  in 
the  vicinity  of  the  border  than  in  districts  to  the  north,  and  the  border  there, 
so  far  as  noted,  is  without  topographic  expression,  the  drift  being  found 
largely  in  depressions,  with  only  a  thin  veneering  on  the  hills.  As  noted 
farther  on,  a  prominent  belt  of  drift  ridges  comes  down  nearly  to  the  di-ift 
border  from  the  northeast  across  southeastern  Madison,  central  St.  Clair, 
eastern  Monroe,  and  northern  Randolph  counties,  and  there  turns  southeast- 
ward, taking  a  course  nearly  parallel  with  the  drift  border  and  scarcely  10 
miles  back  from  it.  Upon  turning  southeastward  this  belt  of  ridged  drift 
becomes  ill-defined,  but  has  been  traced  with  some  certainty  to  central 
Jackson  County  (midway  between  Ava  and  Murphysboro).  As  yet  no  line 
of  ridges  marking  a  continuation  has  been  found  farther  southeast.  It  is 
possible  that  the  sheet  of  drift  which  terminates  at  this  belt  of  ridges  may 
come  to  the  glacial  boundary  in  southern  Illinois,  and  constitute  that 
boundary  from  there  eastward. 

In  southern  Illinois  occasional  low  knolls,  20  feet  or  less  in  height, 
occur  in  the  vicinity  of  the  drift  border,  and  there  appears  to  be  a  slight 
ridging  in  east-west  direction  in  the  southern  portion  of  Williamson  County, 
a  ridging  sufficient  to  influence  the  course  of  streams,  as  indicated  on  a  later 
page  (p.  527).  In  the  vicinity  of  the  Wabash  River,  near  Ridgway,  and 
thence  noi'theastward  to  New  Haven,  Illinois,  there  is  a  belt  of  low  sandy 
knolls  and  ridges,  the  origin  of  which  is  not  clearly  determined.  Possibly 
they  are  entirely  the  result  of  wind  action,  or  they  may  be  due  in  part  to 
glacial  action. 

In  southwestern  Indiana  a  few  places  were  found  where  the  drift 
border  and  districts  immediately  back  of  it  show  a  tendency  to  aggregation 
in  low  knolls  and  ridges.  Perhaps  the  most  conspicuous  instance  is  found 
in  Gibson  County,  near  Fort  Branch,  where  for  a  distance  of  about  3  miles 
along  the  east  side  of  the  Evansville  and  Terre  Haute  Railway  there  is  a 
ridge  of  drift  30  to  50  feet  in  height  and  nearly  a  mile  in  breadth,  whose 
surface  is  quite  undulatory.  From  the  southern  end  of  this  ridge  south- 
westward  into  Posey  County  knolls  10  to  20  feet  in  height  are  of  frequent 
occurrence,  and  in  places  become    so    closely   aggregated    as    to    give    a 


40  THE  ILLINOIS  GLACIAL  LOBE. 

decidedly  movainic  expression  to  the  drift  surface.  Occasional  knolls  and 
low  ridges  of  di-ift  were  found  in  northeastern  Gibson  and  northern  Pike 
counties,  Indiana,  lying  usually  within  5  miles  of  the  glacial  boundarj^ 
No  knolls  or  ridges  of  drift  were  noted  in  the  district  north  of  East  White 
River,  nor  have  any  been  observed  far  back  from  the  glacial  boundary  in 
southwestern  Indiana  and  southei'n  Illinois. 

Reviewing  the  above  statements,  it  appears  that  the  border  is  only  in 
places  marked  by  a  definite  ridge,  and  tliat  there  the  ridge  has  mild  expres- 
sion and  slight  dimensions  compared  with  the  expression  and  dimensions  of 
the  bulky  moraines  formed  at  the  Wisconsin  stage  of  glaciation.  The 
expression  is  also  much  milder  than  that  of  ridges  formed  at  some  distance 
back  from  the  drift  border  in  southwestern  Illinois,  which  pertain  to  the 
Illiuoian  sheet,  descriptions  of  which  are  given  below. 

STRUCTURE  OF  THE  DRIFT  BORDER. 

The  drift  border,  as  here  discussed,  includes  a  belt  several  miles  in 
width,  embracing  a  sufficient  amount  of  territory  to  afford  a  fair  index  of 
the  variations  which  are  displayed  in  the  immediate  vicinity  of  the  border. 

The  discussion  begins  in  Lee  County,  Iowa,  which  is  the  writer's  native 
county,  since  the  sections  of  wells  and  also  natural  exposures  have  been 
studied  more  thoroughly  there  than  at  an}'  other  part  of  the  di'ift  border. 
This  county  is  situated  in  the  extreme  southeast  corner  of  Iowa.  (See  fig.  4). 
During  the  drought  of  1894  and  1895  a  large  number  of  new  wells  were  sunk, 
and  the  writer  had  opportunity  to  make  many  observations  concerning  the 
character  of  the  drift  penetrated  by  them.  The  Illiuoian  drift  sheet  is  found 
to  be  generally  but  10  to  30  feet  in  thickness,  though  on  the  ridge  which 
forms  its  western  limit  the  thickness  is  increased  to  50  feet  or  more.  In 
several  of  the  wells  wliich  were  observed  during  excavation  the  Illiuoian 
drift  is  composed  of  a  brownish,  pebbly  clay,  which  has  been  so  thoroughly 
leached  that  no  response  with  acid  could  be  obtained,  even  where  the  thick- 
ness is  20  feet.  But  in  some  of  the  wells  this  sheet  contains  a  very  cal- 
careous till  which  has  beeii  leached  only  to  a  depth  of  6  or  8  feet.  This 
variability  in  the  amount  of  leaching  is  thought  to  be  due  to  difference  in 
the  derivation  of  the  material.  That  which  is  leached  from  top  to  bottom 
is  probably  made  up  in  large  part  of  the  surface  portion  of  the  older  sheet 
of  drift  which  is  here  overridden.     That  which  is  a  typical  calcareous  till 


STEUCTUEE  OF  THE  DEIFT  BOEDEE.  41 

was  probably  in  part  formed  by  the  ice  in  passing  over  rock  ledges  and  in 
part  collected  from  the  calcareous  portions  of  the  underlying  sheet.  It 
does  not  seem  at  all  probable  that  the  variations  in  the  depth  of  the  leached 
material  are  due  entirely  to  leaching  which  has  occurred  since  the  Illinoian 
sheet  was  deposited.  The  portions  which  are  leached  to  great  depth  seem 
to  be  no  more  readily  pervious  to  water  than  those  in  which  the  leaching 
has  extended  to  a  depth  of  only  6  or  8  feet. 

The  ridge  marking  the  western  limits  of  the  Illinoian  diift,  in  Lee 
County,  is  in  places  thickly  set  with  bowlders,  but  as  a  rule  it  appears  to 
carry  no  more  bowlders  than  the  portion  of  the  same  sheet  in  the  plain 
tracts  immediately  east.  T'he  bowlders  and  smaller  rock  constituents  of 
the  Illinoian  drift  are  found  to  diifer  somewhat  from  those  of  the  sheet 
that  underlies  it,  there  being-  certain  rocks  found  in  it  that  are  not  found 
in  the  underlying  sheet,  while  other  rocks  differ  in  abundance  in  the  two 
sheets.  Several  bowlders  of  red  jaspery  conglomerate,  apparently  from 
the  Huronian  outcrops  north  from  Georgian  Bay,  have  been  found  in  this 
county  on  and  east  of  the  ridge  that  marks  the  Avestern  limits  of  the 
Illinoian  drift,  and  these  are  thought  to  point  decisively  to  the  Labradorian 
invasion.  There  are  also  quartzite  rocks  present  in  the  Illinoian  drift  that 
have  not  been  seen  in  the  sheet  beneath  it  and  which  probably  were  derived 
from  sources  not  far  distant  from  the  Huronian  that  bears  the  jaspery 
conglomerate.  The  cherty  beds  of  the  Burlington  limestone  that  outcrop 
along  the  Mississippi  and  its  tributaries  have  been  incorporated  in  the 
Illinoian  di'ift  sheet  and  transported  westward  to  the  extreme  limits  of  that 
sheet.  They  point  with  certainty  to  the  influence  of  the  Labradorian 
invasion. 

The  Illinoian  till  sheet  in  Lee  County,  as  also  in  counties  to  the  north, 
is  separated  from  the  underlying  Kansan  till  sheet  by  a  weathered  zone 
accompanied  by  beds  of  black  muck  and  peaty  material.  This  was  first 
brought  to  the  writer's  notice  about  ten  years  ago,  in  a  well  sunk  near  the 
village  of  Yarmouth,  in  Des  Moines  County.  For  this  reason,  and  because 
it  is  not  liable  to  be  a  source  of  confusion  by  duplication  in  other  parts  of 
the  g'laciated  region,  the  name  Yarmouth  has  been  proposed  to  cover  the 
interglacial  interval  between  the  Kansan  and  Illinoian.-'     The  village  of 

'  The  -vreathered  zone  (YarmoutU)  between  the  Kansan  and  Illinoian  till  sheets,  by  Frank 
Leverett:  Proc.  Iowa  Acad.  Sci.,  Vol.  V,  iip.  81-86,  1898;  Jour.  Geol.,  Vol.  VI,  1898,  pp.  238-243. 


42  THE  ILLINOIS  GLACIAL  LOBE. 

Yarmouth  is  situated  about  20  miles  northwest  of  Burlington,  the  county- 
seat  of  Des  Moines  County,  on  the  line  of  the  Burlington  and  Western 
Railway.  It  stands  on  the  ridge  which  marks  the  western  border  of  the 
Illinoian  till  sheet.  The  well  above  refeiTed  to,  which  first  suggested  to 
the  writer  the  occurrence  of  two  distinct  sheets  of  till  in  southeastern  Iowa, 
was  made  by  William  Stelter,  on  the  border  of  the  village  of  Yaraiouth. 
The  writer  A-isited  the  well  soon  after  it  was  bored  and  made  out  the  follow- 
ing section  fi-om  the  material  exposed  in  the  dump  : 

Section  from  well  of  William  Stelter,  near  Yarmouth,  Des  Moines  County,  Iowa. 

Feet. 

Soil  and  loam  (lowan  loess) 4 

Brownish  yellow  till  (Illinoian) 20 

Gray  till  (Illinoian) 10 

Peat  bed  with  twigs  and  bones  (Yarmouth) 15 

Gray  or  ashy  sandy  clay,  containing  wood  (Yarmouth) 12 

Fine  sand  (Yarmouth).... 16 

Yellow  sandy  till  with  few  pebbles  (Kansan) 33 

Total  depth - 110 

The  bones  found  in  the  peat  were  sent  to  the  Smithsonian  Institution 
and  there  identified  by  Dr.  F.  W.  True,  as  follows: 

(1)  A  portion  of  the  pelvis  and  the  upper  part  of  the  femur  of  the 
wood  rabbit  {Lepws  sylvaticus);  (2)  the  scapula  of  the  common  skunk 
(jSIepliiticus  mephitica).  The  occurrence  of  these  bones  was  first  announced 
by  McGee,  in  the  Eleventh  Annual  Report  of  this  Survey,  and  referred  to 
a  "forest  bed,"  but  without  more  definite  reference.^ 

The  thickness  of  the  peat  in  this  well  and  of  the  associated  sand}-  clay 
charged  with  wood,  is  an  impressive  evidence  of  an  interglacial  interval  of 
considerable  length.  But  in  the  writer's  opinion  it  furnishes  less  weighty 
evidence  than  is  afibrded  by  the  general  weathering  which  took  place  on 
the  surface  of  the  Kansan  sheet  prior  to  the  deposition  of  the  Illinoian  di-ift. 
The  peat  naturally  aiTests  attention  quicker  than  the  reddened  zone,  but  is 
more  restricted  in  its  development;  yet  several  instances  of  the  occurrence 
of  beds  such  as  the  one  at  Yarmouth  have  been  brought  to  the  writer's 
notice.  They  appear  to  be  rather  more  prevalent  along  the  extreme  border 
of  the  Illinoian  than  at  points  some  miles  back  beneath  it ;  but  instances 
occur  all  over  the  portion  of  southeastern  Iowa  invaded  by  the  Illinois  lobe. 

'  See  p.  495  of  report  cited,  published  in  1891. 


/ 


STRUCTURE  OF  THE  DRIFT  BORDER.  43 

The  peaty  dej)osits  are  usually  found  associated  with  sandy  beds,  while  the 
soil  and  weathered  zone  cap  a  sheet  of  till  or  stiff  clay. 

In  many  of  the  wells  in  southeastern  Iowa,  and  also  in  natural  expo- 
sures, a  reddened  or  deeply  oxidized  clay  is  found,  instead  of  peat  or  muck, 
between  the  Illinoian  and  Kansan  sheets.  This  constitutes  usually  the 
weathered  surface  of  the  Kansan,  and  appears  to  have  been  originally  a 
calcareous  till,  like  the  remainder  of  that  deposit.  Acid  tests  have  fre- 
quently been  made  in  freshly  dug  wells  and  in  natural  exposures  with  a 
view  to  determine  the  amount  of  leaching  prior  to  the  deposition  of  the 
Illinoian  till  sheet.  It  is  found  that,  as  a  rule,  no  response  to  acid  is  obtained 
at  less  than  4  feet,  and  often  the  response  does  not  set  in  within  6  feet  of  the 
top  of  the  buried  Kansan  sheet.  In  the  cases  where  leaching  occurs  within 
4  feet  of  the  surface,  it  seems  safe  to  infer  that  a  portion  of  the  leached 
material  liad  been  removed  prior  to  the  deposition  of  the  Illinoian  till  sheet. 
While  the  leached  material  usually  bears  a  striking  resemblance  to  the 
underlying  calcareous  till,  exposures  have  been  found  in  which  it  differs  in 
general  appearance  and  is  perhaps  a  deposit  of  different  origin.  These 
deposits  also  are  thoroughly  leached  at  surface.  This  weathered  zone  is  so 
conspicuous  throughout  the  region  of  overlap  of  the  Illinoian  upon  the  Kan- 
san that  the  writer  has  satisfied  himself  of  the  occurrence  of  a  long  interval 
of  deglaciatioia  prior  to  the  deposition  of  the  Illinoian  drift.  Instances  of 
the  occurrence  of  this  weathered  zone,  and  also  evidences  of  erosion  between 
the  Kansan  and  Illinoian  glaciations,  are  presented  below. 

With  this  brief  explanation  of  the  drift  border  in  the  part  most  familiar 
to  the  writer  the  discussion  will  pass  to  the  north  part  of  the  border  in 
southern  Wisconsin,  and  proceed  thence  southward. 

From  the  descriptions  of  the  drift  in  southern  Wisconsin,  presented 
in  the  Greology  of  Wisconsin  and  in  Chamberlin  and  Salisbury's  paper  in 
the  Sixth  Annual  Report  of  this  Survey,  it  appears  that  the  drift  border  is 
characterized  by  occasional  gravelly  knolls  and  ridges,  some  of  which  are 
of  distinct  esker  type.  There  are  also  gravel  and  sand  deposits  on  plane- 
surfaced  tracts,  but  the  greater  portion  of  the  drift  appears  to  be  a  moderately 
stony  till  Avith  an  adhesive  clayey  matrix.  This  phase  of  the  drift  border 
continues  southward  across  northwestern  Illinois.  It  is  found  that  some  of 
the  preglacial  valleys  near  the  drift  border  were  filled  with  a  deposit  of  fine 
silt   or    clay    containing  very  few  pebbles.     These    deposits    characterize 


44  THE  ILLINOIS  GLACIAL  LOBE. 

^^alleys  which  had  eastward  drainage  in  preglacial  times  and  are  probably 
to  be  attributed  to  the  ponded  waters  held  in  front  of  the  ice  and  laden 
with  laro-e  amounts  of  fine  sediment  carried  by  the  waters  issuing  from  the 
ice.  Portions  of  the  border  in  northwestern  Stephenson,  southeastern  Jo 
Daviess,  and  northwestern  Carroll  counties  are  liberally  strewn  with  bowl- 
ders of  granite  and  other  distantly  derived  rocks.  The  number  appears  to 
be  greater  within  the  first  5  miles  back  from  the  drift  border  than  at  more 
remote  points.  In  this  portion  of  the  drift  border  the  loess  coating  is  thin 
except  in  the  immediate  vicinity  of  the  Mississippi  Valley,  its  average  depth 
being  scarcely  more  than  5  feet.  On  slopes  it  is  largely  removed,  leaving 
the  surface  of  the  glacial  drift  exposed  to  view. 

The  interval  between  the  southern  point  of  the  Driftless  Area  near 
Savanna  and  the  northernmost  point  at  which  the  Illinoian  drift  border  is 
recognized  on  the  Iowa  side  of  the  Mississippi  is  about  50  miles.  A  direct 
line  across  it  traverses  a  low  plain  covered  with  a  very  bowldery  sheet  of 
lowan  drift,  described  by  McGee,  which  is  nearly  free  from  deposits  of 
loess  in  the  middle  portion,  but  which  is  bordered  in  the  peripheral  portion 
on  the  north  east  and  south  by  loess-covered  drift.  No  recognition  of  the 
Illinoian  drift  has  been  made  in  this  interval  along  the  direct  line  of  con- 
nection. But  it  has  been  identified  in  Davenport  and  at  points  west  of  that 
city  in  Scott  and  eastern  Muscatine  counties,  Iowa.  It  is  therefore  certain 
that  the  Illinois  lobe  extended  beyond  the  Mississippi  River  at  least  as  far 
north  as  eastern  Scott  County. 

Prof  J.  A.  Udden  has  recently  published  an  important  table  showing- 
notable  differences  in, the  rock  constituents  of  the  lUinoian  and  the  under- 
lying drift  sheets  of  Muscatine  County,  from  which  it  appears  tliat  the 
constituents  of  the  Illinoian  are  largely  derived  from  outcrops  to  the  east.^ 

Exposures  of  drift  in  Davenport  and  Muscatine,  Iowa,  were  made  the 
subject  of  joint  investigation  by  Prof  Samuel  Calvin  and  Dr.  H.  Foster 
Bain,  of  the  Iowa  Ceological  Survey,  Prof  J.  A.  Udden,  and  the  writer,  in 
November,  1897,  and  there  was  entire  unanimity  in  the  interpretations. 
At  Davenport  the  first  exposure  examined  was  one  previously  described  by 
McGee,-  which  is  situated  at  the  northwest  corner  of  Sixth  and  Harrison 

'  Iowa.  Geol.  Survey,  Vol.  IX,  1S99,  p.  330. 

2  Eleventh  Ann.  Kept.  U.  S.  Geol.  Survey  (for  1889-90),  1891,  p.  491;  also  tig.  77. 


STEUCTUEB  OF  THE  DRIFT  BORDER.  45 

streets.  The  occurrence  of  a  distinct  soil  and  weathered  zone  between 
the  loess  and  the  upj^er  or  Illinoian  till  sheet  is  a  feature  not  noted  by 
McGee;  with  this  exception  his  description  applies  well  to  the  exposure. 
The  section,  as  determiijed  November,  1897,  is  as  follows: 

Section  of  drift  at  corner  of  Sixth  mid  Harrison  streets,  Davenport,  loica. 

Feet. 
lowan  loess',  partly  eroded 8 

Black  soil  1  foot,  with  Illiuoian  till  surface  leached  and  reddened  to  a  depth  of  3  feet  in  theSan- 
gamou  interglacial  stage;  total 4 

Brown  calcareous  till,  with  a  few  calcareous  nodules ;  traces  of  horizontal  bedding  near  bottom, 
but  with  few  vertical  fissures  or  seams,  a  characteristic  Illinoian  till 7 

Brown  till,  calcareous,  with  numerous  vertical  fissures  and  seams,  and  occasional  horizontal 
sand  partings,  with  tendency  to  break  in  cubical  blocks,  a  characteristic  oxidized  Kansan  till .     8-10 

Blue-gray  till,  calcareous,  with  occasional  horizontal  saud  partings  and  numerous  vertical  seams, 
also  tendency  to  break  in  cubical  blocks;  bowlder-like  masses  of  gravelly  sand  often  2  or  3 
feet  in  diameter,  in  some  cases  showing  crumpling  of  beds,  occur  in  the  lower  part  of  the 
exposure;  a  characteristic  unoxidized  Kansan  till;  entire  depth 35-40 

Fine  sand,  appearing  only  on  Harrison  street,  at  base  of  exposure 3 

Total,  about , 70 

The  base  of  this  exposure  stands  about  50  feet  above  the  level  of  the 
Mississippi  River,  while  the  top  of  the  exposure  is  nearly  at  the  level  of 
the  uplands.  In  this  exposure  no  leached  zone  appears  at  the  junction  of 
the  Illinoian  and  Kansan,  probably  because  of  removal  by  the  Illinois  ice 
lobe.  '  The  change  in  physical  character  upon  passing-  from  the  brown  till 
of  the  Illinoian  to  that  of  the  Kansan  is  very  striking.  The  Illinoian  may 
be  denoted  a  friable  or  crumbling  till,  while  the  Kansan  is  a  caking  till 
where  characteristically  developed. 

The  next  exposure  examined  presented  a  weathered  zone  and  evidence 
of  erosion  between  the  Illinoian  and  Kansan,  and  also  showed  the  lowan 
loess  in  its  full  thickness.  It  is  found  along  Eighth  street  in  a  steep  descent 
between  Myrtle  and  A'^ine,  and  is  as  follows: 

Section  of  drift  along  Eighth  street,  beticeen  Myrtle  and  Vine  streets,  Davenport,  Iowa. 

Feet. 

lowan  loess 80 

Reddish-brown  surface  of  Illinoian  till  sheet,  leached  and  stained  durihg  Sangamon  inter- 
glacial stage 2i  to    3 

Brown  calcareous  till,  crumbling  readily ;  a  characteristic  Illinoian  till 15 

Ash-colored  gummy  clay  with  black  streaks,  apparently  of  humus,  representing  the  Yarmouth 

interglacial  stage 2    to    3 

Brown  till,  calcareous,  fracturing  in  cubical  blocks,  color  changing  to  grayish  blue  at  12  to  15 
feet ;  characteristic  Kansan  till 25 

Total,  about 1^ 


46  THE  ILLINOIS  GLACIAL  LOBE. 

The  surface  of  the  Kausau  apj^ears  to  have  been  subjected  to  some 
erosiou,  for  it  drops  down  about  15  feet  iu  a  distance  of  20  rods  in  passing 
toward  the  river  valley.  This  sloping  surface  of  the  Kansan  is  leached  and 
humus  stained,  and  the  Illinoian  till  mantles  it  with  a  bed  of  nearly  uniform 
thickness,  thus  presenting  an  upper  surface  nearly  parallel  with  that  of  the 
eroded  Kansan. 

In  the  autumn  of  1894  the  writer  observed  several  exposures  of  a  soil 
and  weathered  zone  in  ravines  in  western  Scott  and  eastern  Muscatine 
counties,  between  what  are  interpreted  to  be  the  Kansan  and  Illinoian  till 
sheets.  They  are  not  conspicuous  in  eastei-n  Muscatine  County,  but  may 
be  seen  both  north  and  south  of  Blue  Grass,  in  Scott  County.  The 
exposures  noted  are  not  sufficiently  deep  to  show  the  lower  till  sheet  to 
good  advantage,  but  the  upper  is  well  displayed  and  has  the  characteristic 
appearance  of  the  Illinoian.  Its  thickness  is  but  a  few  feet — in  some  places 
only  6  or  8  feet,  and  seldom  more  than  15  feet.  The  Yarmouth  soil  and 
weathered  zone  is  represented  by  a  gummy  black  or  gray  clay,  changing 
below  to  a  reddish-brown  till.  The  Sangamon  soil  and  weathered  zone  is 
represented  by  a  similar  dark  gummy  clay  and  a  leached  and  reddened 
till  surface.  The  lowan  loess  in  this  locality  is  only  about  8  feet  in  depth, 
and  is  more  compact  than  the  bluff  loess  found  in  Davenport. 

At  Muscatine  the  party  of  geologists  above  mentioned  examined 
exposm-es  in  the  east  part  of  the  city,  in  the  east  bluif  of  Mad  Creek,  and 
east  from  there  on  or  near  Second  street  and  on  Park  avenue.  These  all 
occur  in  a  lowland  tract  bordering  the  lower  course  of  the  creek  and 
occupying  the  interval  between  the  creek  and  Mississippi  River.  Its 
general  elevation  is  about  80  feet,  and  the  highest  points  barely  reach  100 
feet  above  the  low  water  in  the  river.  The  latter  are  found  in  a  low  ridge 
following  the  bluff  of  the  Mississippi.  ,  This  lowland  carries  on  its  sm-face 
a  nearly  pebbleless  silt  several  feet  in  depth,  at  the  bottom  of  which  there 
are  occasional  tliin  deposits  of  sand  resting  on  till.  The  tliickness  of  silt 
and  sand  is  scarcely  10  feet,  or  less  than  one-half  of  the  tliickness  of  the 
lowan  leess  on  neigliboring  uplands.  It  seems  doubtful  whether  the 
deposit  is  of  lowan  age  or  is  to  be  correlated  witli  the  loess.  The  -s-iew 
that  it  is  alluvial  seemed  to  us  more  probable.  The  till  beneath  this  silt 
and  sand  was  found  to  carry  numerous  large  bt)wlders,  some  of  them  being 


STRUCTURE  OF  THE  DRIFT  BORDER.  47 

at  its  surface.  It  also  presents  the  crumbling  texture  characteristic  of  the 
lUinoian  till  sheet.  It  shows  very  little  surface  leaching,  response  to  acid 
being  readily  obtained  at  a  foot  or  less.  This  absence  of  a  marked 
weathered  zone  was  interpreted  to  be  due  to  removal  by  a  stream  which 
deposited  the  sand  and  silt,  rather  than  to  the  time  interval  being  too  brief 
for  the  development  of  a  weathered  zone.  The  slig-ht  inequalities  in  its  surface 
appear  to,  be  due  to  erosion.  This  till  is  referred  with  some  confidence  to 
the  lUinoian  because  of  its  physical  texture  and  characteristics.  Its  thick- 
ness, as  exposed  on  Second  street,  is  about  30  feet.  Beneath  the  till  there 
are  beds  of  fine  sand  and  silt,  in  the  midst  of  which  are  thin  layers  of  clay, 
bearing  pebbles  up  to  2  inches  or  more  in  diameter.  Similar  beds  in  the 
southwest  part  of  Muscatine  separate  the  Illinoian  and  Kansan  till  sheets, 
as  shown  below. 

In  the  southwest  part  of  Muscatine  the  altitude  of  the  Mississippi  bluff 
is  160  to  200  feet  above  the  river,  and  a  remarkably  full  series  of  diift 
deposits  is,  or  has  been,  exposed.  In  1894  a  grading  on  Grreen  street 
afforded  an  excellent  exposure  of  the  upper  part  of  the  series,  beginning  at 
a  level  about  165  feet  above  the  river  and  extending  down  50  feet,  but  this 
is  now  concealed  by  grass.  The  lower  part  of  the  bluff  is  still  exposed  in 
the  large  clay  and  sand  pits  west  of  Green  street.  The  exposure  on  Green 
street  was  examined  by  the  writer  when  freshly  graded  (in  1894),  and  those 
west  of  Green  street  were  examined  by  the  party  of  geologists  in  November, 
1897.     The  sections  are  as  follows: 

Section  on  Green  street,  Muscatine,  Iowa. 

Feet. 

lo  wan  loess,  partly  eroded 10 

Brownish-black  silt  at  base  of  loess , ^ Uto   2 

Pebbly  black  soil  (Sangamon) 3 

Leached  brown  till  (Illinoian) 6 

Brown  till,  unleached,  many  bowlders  near  base  (Illinoian) 12 

Calcareous  silt 6    to    8 

Calcareous  till  of  brown  color,  probably  Kansan 10 

Section  on  Mississippi  bluff  west  of  Green  street,  Muscatine,  Iowa. 

Teet. 

Loess,  perhaps  notinsitu 0  to   5 

Till  of  brown  color,  eroded,  of  fri.ible  crumbling  texture,  characteristic  of  Illinoian  drift. . .  1-5  to  25 
Beds  of  sand  with  even  upper  surface  but  uneven  lower  surface,  containing  a  few  bowlderets 

and  cobblestones,  but  not  as  a  rule  stony 5    to  12 

Gray  till,  with  vertical  cracks  lined  with  brown  material,  probably  Kansan 8   to  20 


48  THE  ILLINOIS  GLACIAL  LOBE. 

Section  on  Mississippi  Muff  west  of  Green  street,  Muscatine,  Iowa — Continued. 

Feet. 
Disturbed  beds  of  sand  with  folds  that  appear  to  have  a  i^revailing  east-west  treud,  us  if 

shoved  from  the  north 4   to  12 

Blue-black  till  with  fragments  of  wood,  very  thickly  set  also  with  small  stones  and  very 
calcareous,  not  characterized  by  weathered  seams,  possibly  pre-Kansan,  exposed  only  a  few 

rods 0   to   8 

Peaty  bed,  exposed  only  for  a  few  feet 4  to    1 

Sand,  perhaps  from  decomposed  Coal  Measure  Sandstone 1    to   2 

Coal  Measure  Sandstone  exposed  at  bottom  of  pit  at  level  probably  50  feet  above  river. 

Total 60 

The  blue-black  till  at  the  base  of  this  exposure  is  thought  by  Bain  to 
be  very  similar  in  physical  texture  to  some  of  the  supposed  pre-Kansan 
deposits  of  southern  Iowa.  The  writer  has  observed  several  instances  of 
similar  material  near  the  bottom  of  the  drift  series  in  southeastern  Iowa.  It 
is  thought  best  not  to  include  it  in  the  Kansan  unless  these  suspicions  are 
removed. 

In  the  Muscatine  cemetery,  on  the  bluff  back  of  the  exposures  just 
described,  at  an  altitude  about  200  feet  above  the  river,  a  well  passed 
through  215  feet  of  glacial  deposits,  including  loess  and  sand.  The  drift  is 
mainly  blue  till,  but  beds  of  sand  such  as  outcrop  in  the  exposures  near 
Green  street  were  passed  through. 

For  a  few  miles  in  the  portion  of  the  Illinoian  drift  border  adjacent  to 
the  southwestern  flowing  portion  of  Cedar  River,  in  Muscatine  County, 
sand  dunes  and  a  general  coating  of  sand,  drifted  probably  by  wind  from 
the  plains  bordering  the  Cedar  River,  form  a  mantle  of  considerable  depth 
on  the  crest  of  the  terminal  ridge,  and  conceal  the  structure  of  the  ridge,  so 
that  wells  afford  the  only  means  for  obtaining  information  concerning  it. 
Several  deep  wells  have  been  made  which  penetrate  from  120  to  300  feet 
of  drift,  the  least  depth  at  which  rock  was  found  being-  120  feet.  These 
wells  usually  penetrate  a  large  amount  of  till,  but  there  are  thin  beds  of 
sand  associated  with  the  till  at  various  levels.  In  some  cases  a  hard  till  is 
found  at  considerable  depth,  which,  it  is  probable,  is  as  old  as  the  Kansan, 
and  possibly  is  pre-Kansan  in  age.  The  following  list  of  wells  in  Musca- 
tine County  will  serve  to  set  forth  the  variatioiis  in  sti'ucture  and  the  great 
depth  of  drift.  Tlie  list  begins  at  the  noi-theast  part  of  the  county  and  pro- 
ceeds southwestward  along  the  ridge.  For.  several  of  the  sections  the  writer 
is  indebted  to  Prof  J.  A.  Udden. 


STflUCTUEE  OF  THE  DEIFT  BORDER. 

Beep  loells  along  Illinoian  drift  border  in  Muscatine  County^  loica. 


49 


Owner  or  location. 

Altitude 
above  tide. 

Depth. 

Kemarka. 

Feet. 

Feet. 

S.  Hayden,  sec.  8,  T.  78,  E.  1  E 

800 

120 

Mainly  till ;  inflammahle  gas  from  near 
bottom  of  drift. 

Sfip  33  T  78  R  1  E    .               

730 

261 

Clay,  80  feet;  quicksand,  8  feet;  coarse 
sand  near  bottom. 

Sec  9T78E1'W          

710 

240 

Sand,  or  sandy  till,  90  feet ;  blue  clay,  140 
feet;  sand  and  gravel,  10  feet. 

W.   Feldholm,   2   miles  south  of 

750 

100 

Silt,  5  feet;  sand,  with  few  pebbles,  30 

Durant. 

feet;  hard  blue  till,  65  feet. 

Three  miles  south  of  Wilton 

720 

300 

No  rock  entered. 

J.  Denkman,  sec.  12,  T.  78,  R.  1  W  .. 

770 

158 

Clay,  140  feet;    silt  and  sand,  18  feet; 
rock  at  bottom. 

F.  D.  Wood,  sec.  27,  T.  77,  E.  3  W. . . 

750 

208 

Mainly  blue  clay  with  few  pebbles;  no 
rock  struck. 

A.  Wiggam,  sec.  10,  T.  76,  R.  3  W. .. 

750 

170 

Loess,  12  feet;  yellow  tiU,  38  feet;  grav- 
elly sand,  25  feet;  blue  till,  25  feet: 
yellow  cemented  gravel,  10  feet ;  very 
hard  blue  till,  60  feet;  sand,  8  feet. 

Sec.  30,  T.  76,  E.  3  W 

720 

154 

Mainly  till;  gravel  at  bottom. 

L.  Eppelry,  3  miles  north  of  Letts. 

735 

200 

No  rock  entered. 

A.  Cone,  sec.  24,  T.  76,  E.  4  W 

660 

200 

Till,  130  feet;   very  hard  till,  60  feet; 
sand  at  bottom,  10  feet. 

In  northern  Louisa  County,  near  Letts,  several  wells  have  obtained 
inflammable  gas  in  sand  below  till  at  depths  of  100  to  150  feet.  These 
wells  are  situated  just  within  (south  of)  the  ridge  marking  the  limits  of  the 
Illinoian  drift,  at  a  level  perhaps  50  feet  below  its  crest,  or  about  675  feet 
above  tide.  It  is  reported  by  the  residents  that  beds  of  black  muck  and 
peaty  material  are  found  closely  associated  with  this  gas,  and  it  is  probable 
that  the  gas  is  derived  from  the  decomposition  of  organic  matter  in  these 
beds.  The  horizon  seems  rather  low  for  the  Yarmouth  beds,  unless  the 
Kansan  till  sheet  has  been  eroded.  Prof.  F.  M.  Witter,  of  Muscatine,  Iowa, 
has  presented  a  brief  discussion  of  these  wells  in  the  American  Geologist.^ 

The  drift  in  the  vicinity  of  Columbus  Junction  may  exceed  300  feet 
in  depth.  A  well  made  by  Dr.  Daniel  Overhalt  in  the  Iowa  River  Valley, 
near  Columbus  Junction,  at  a  level  about   130  feet  below  the  uplands, 


'  Am.  Geologist,  May,  1892,  pp.  319-321. 


MON  XXXVIII- 


50  THE  ILLINOIS  GLACIAL  LOBE. 

reached  a  depth  of  164  feet  without  entering  rock;  the  bottom  of  the  well 
is  estimated  to  be  but  416  feet  above  tide.  The  following-  section  of  this 
well  is  reported  by  the  well  diiller,  L.  Williams,  of  Columbus  City: 

Section  in  loell  in  Iowa  Biver  Valley  near  Columbus  Junction. 

Feet. 

Alluvium y 

Blue  pebbly  clay 72 

Sand 2 

Blue  clay 14 

Sand 68 

Total 164 

Di-.  Overhalt  has  a  well  on  the  bluff  back  of  Columbus  Junction  at  an 
altitude  130  feet  above  the  well  just  noted,  which  reached  a  depth  of  166 
feet.  It  penetrates  about  35  feet  of  loess  and  yellow  till,  beneath  which  it 
is  mainly  in  a  blue  till  to  within  6  feet  of  the  bottom,  where  sand  and 
gravel  are  struck.  It  is  probable  that  the  blue  till  in  this  and  the  following- 
two  sections  is  Kansan.  A  well  made  for  Hon.  J.  W.  Garner  at  Columbus 
City  penetrated  only  13  feet  of  loess  and  yellow  till,  beneath  which  157 
feet  of  blue  till  was  passed  through  before  a  water-bearing-  sand  was  found. 
L.  Williams's  well,  in  Columbus  City,  passed  through  20  feet  of  loess  and 
yellow  till  and  then  penetrated  108  feet  of  blue  till  before  entering  water- 
bearing sand.  Within  2  miles  west  or  south  of  Columbus  City  rock  is 
found  at  depths  of  only  20  to  40  feet,  and  the  drift  is  largely  a  yellow  till. 

Near  Cairo,  in  Louisa  County,  Iowa,  two  wells  on  the  crest  of  the  outer 
ridge  of  the  Illinoian  drift  sheet,  at  an  altitude  of  about  750  feet  above  tide, 
reached  a  depth  of  130  feet  without  encountering  rock.  They  are  mainly 
through  till,  much  of  which  is  probably  Kansan.  On  the  outer  face  of  the 
ridge,  near  the  base,  at  an  elevation  of  50  feet  below  the  crest,  a  well  was 
sunk  by  R.  Cotter  which  enters  rock  at  about  50  feet.  Rock  is  also  exposed 
in  the  bluff  of  Long  Creek,  north  of  Cairo,  beneath  about  60  feet  of  drift, 
mainly  till. 

Along  the  outer  ridge  of  the  Illinoian  drift  in  northwestern  Des  Moines 
County  several  deep  wells  have  been  sunk,  some  of  which  penetrate  a  bed 
of  peat  or  muck  at  about  the  level  of  the  base  of  the  ridge  and  the  surface 
of  the  Kansan  sheet  of  drift.  It  is  here  that  the  Yarmouth  section  given 
above  (p.  42)  is  found. 

In  some  places  along  the  outer  ridge  of  the  Illinoian  drift  wells  have 


STRUCTURE  OP  THE  DRIFT  BORDER.  51 

passed  below  the  level  of  the  outer  border  plain  before  entering-  the  black 
muck  which  is  thought  to  separate  the  lUinoiau  drift  from  the  Kansan.  In 
such  cases  the  well  is  supposed  to  have  struck  into  a  valley  which  had  been 
excavated  in  the  earlier  sheet  of  drift,  though  there  is  a  bare  possibility 
that  an  older  soil  horizon  is  struck.  The  following  section  of  a  well  on 
the  farm  of  F.  Smith,  about  a  mile  south  of  Yarmouth,  will  illustrate  the 
condition  just  mentioned: 

Section  in  well  on  farm  of  F.  Smith,  a  mile  south  of  Yarmouth,  loica. 

Teet. 

Yellow  till,  becoming  gray  below  (Illinoian) 36 

Sand,  with  thin  beds  of  blue  clay  and  also  of  cemented  gravel,  probably  in  part  Illinoian  and  in 

part  alluvial 73 

Black  muck,  containing  wood  (Yarmouth) 6 

Sand  and  gravel,  probably  alluvia] 8 

Gray  silt,  apparently  pebbleless,  probably  alluvial 15 

Blue  till  (Kansan) 42 

Depth 180 

This  well  is  on  the  crest  of  the  ridge  at  a  level  60  or  70  feet  above  the 
outer  border  plain.  The  black  muck  is  therefore  at  a  level  about  40  feet 
below  the  plain.  A  well  in  the  neighboring  section  on  the  south,  at  an  ele- 
vation 25  feet  lower,  enters  rock  at  a  depth  of  182  feet. 

One  of  the  thickest  drift  sections  found  along  this  drift  border  is  in  a 
well  made  by  Anton  Totemeir  near  New  London,  Iowa,  in  sec.  19,  T.  71, 
R.  4  W.,  which  struck  rock  at  a  depth  of  276  feet.  The  section  of  the  well 
indicates  that  only  the  upper  40  feet  should  be  referred  to  the  Illinoian  di-ift 
sheet.     The  section  as  reported  by  Mr.  Totemeir  is  as  follows: 

Section  in  well  of  Anton  Totemeir,  near  Neiv  London,  loica. 

Feet. 

Pebbly  yellow  clay  (Illinoian) 30 

Pebbly  blue  clay  (Illinoian) 10 

Deeply  stained,  reddish-browu  pebbly  clay  (Kansan) 12 

Blue  pebbly  clay,  with  thin  beds  of  sand,  possibly  including  pre-Kausan  as  well  as  Kansan 224 

Total 276 

The  well  mouth  being  about  750  feet  above  tide,  or  240  feet  above  the 
Mississippi  River  in  Burlington,  the  rock  floor  at  this  well  is  but  a  little 
lower  than  the  bed  of  the  present  Mississippi  at  Burlington.  Of  the  several 
wells  along  this  ridge  in  Des  Moines  County  none  have  been  found  to  enter 
rock  at  less  than  120  feet,  and  probably  at  least  half  this  drift  is  older  than 
the  Illinoian. 


52  THE  ILLINOIS  GLACIAL  LOBE. 

Along  tlie  ridge  in  southeastern  Henry  County,  as  in  northwestern 
Des  Moines  County,  wells  not  infrequently  pass  through  a  bed  of  muck  or 
peat  at  the  base  of  the  Illinoian  drift  sheet.  In  a  well  made  bj-  Andi-ew 
Johnson,  li  miles  south  of  New  London,  there  were  logs  and  wood,  occu- 
pying a  space  of  nearly  4  feet,  found  at  a  depth  of  40  to  45  feet  from  the 
surface.  The  writer  obtained  specimens  of  the  wood  and  of  peaty  material 
associated  with  it,  which  await  specific  identification.  Mr.  Johnson  reports 
the  section  of  the  well  to  be  as  follows : 

Section  in  loell  of  Andreio  Johnson,  1^  miles  south  of  Neic  London,  Iowa. 

Feet. 

Yellow  clay,  without  pebbles  (loess) 6 

Pebbly  yellow  clay  (Illinoiau) 20 

Sand 3 

Blue  pebbly  clay  (Illinoian) '. 12 

Peat  and  wood  (Yarmouth ) 4 

Gray  gummy  clay,  with  few  pebbles  (Yarmouth) 10 

Total 55 

A  well  made  by  J.  M.  Lee,  3  miles  northeast  of  New  London,  passed 
through  a  bed  of  black  muck  containing  wood,  just  before  entering  rock,  at 
a  depth  of  105  to  110  feet.  This  probably  underlies  the  Kansan  sheet  of 
drift. 

The  drift  of  Lee  County,  as  of  counties  to  the  north,  belongs  mainly  to 
the  sheet  which  underlies  the  Illinoiau.  Numerous  exposures,  and  also 
well  sections,  show  the  Illinoian  drift  to  have  a  thickness  of  but  20  to  30 
feet  on  the  plain  east  of  the  terminal  ridge,  and  30  to  70  feet  on  the  ridge. 
The  average  thickness  of  the  combined  drift  sheets  in  the  county  is  23i'ob- 
ably  at  least  100  feet.  On  the  borders  of  the  Mississippi  the  thickness 
exceeds  300  feet,  as  shown  bv  a  well  on  the  bluff  north  of  Fort  Madison 
and  another  at  Mont  Clare.  The  deposit  of  loess  coating  the  Illinoian  drift 
in  this  county  has  an  average  depth  of  only  about  6  feet.  Between  the  loess 
and  the  Illinoian  drift  there  is  a  well-defined  soil  (Sangamon),  nsualh"  of 
black  color.  At  the  top  of  the  Illinoian  drift  there  is  often  a  mucky  clav 
containing  only  fine  pebbles,  but  the  greater  part  is  a  stony  till  with 
occasional  bowlders  and  numerous  rock  fragments  1  to  6  inches  in  diameter. 
As  noted  above,  this  sheet  of  drift  is  often  so  thoroughly  leached  from  top  to 
bottom  tliat  no  response  with  acid  can  be  obtained.  Whether  this  feature 
is  notably  characteristic  of  the  drift  border  for  some  distance  to  the  north 
;ind  sontli  has  not  been  determined. 


STRUCTURE  OF  THE  DRIFT  BORDER.  53 

Along  the  crest  of  the  terminal  ridge  from  Skunk  River  southward  to 
West  Point  numerous  wells  have  been  sunk  to  a  depth  of  60  feet  and  a  few 
to  greater  depth.  They  penetrate  till  the  greater  jjart  of  the  depth,  though 
in  one  instance  the  lower  50  feet  is  sand  and  gravel.  The  thickness  of  the 
drift  ranges  from  about  80  to  120  feet  or  more.  Of  this  the  lower  40  or  50 
feet  is  older  than  the  Illinoian.  Several  of  the  wells  have  passed  through 
peat,  containing  wood,  at  about  the  level  of  the  base  of  the  ridge,  and 
there  is  an  excellent  exposure  of  a  black  muck  below  the  Illinoian  drift  in 
a  ravine  about  a  mile  northeast  of  West  Point  on  the  east  slope  of  the  ridge. 
At  this  exposure  the  following  section  is  found: 

Section  in  a  ravine  about  a  mile  northeast  of  West  Point,  Iowa. 

Feet. 

Yellow  silt  or  loess  (lowan) (> 

Soil,  "with  aahy  gray  subsoil  (Sangamon) 5 

Brown  till  containing  many  bowlders  (Illinoian) 15 

Black  mucky  soil  witli  gray  subsoil  (Yarmouth) 6 

Brown  clay  with  few  pebbles  (Kansan)  exposed 15 

Total 47 

The  deepest  well  section  obtained  on  this  ridg-e  is  at  the  residence  of 
Andrew  Foggy,  sec.  16,  T.  69,  R.  5  W.,  and  this  differs  from  other  well 
sections  in  that  neighborhood  in  containing  a  large  amount  of  sand  in  tlie 
lower  part.  From  observations  in  a  neighboring  ravine  and  Mr.  Foggy's 
statements  concerning  material  penetrated  in  the  well,  the  following  section 
is  prepared: 

Section  in  well  of  Andrew  Foggy,  near  West  Point,  Iowa. 

Feet. 

Y'ellow  silt  or  loess  (lowan) 6 

Black  soil  with  gray  subsoil  (Sangamou) 4 

Yellow  till  (Illinoian) 20 

Sand,  aii'ording  weak  vein  of  water  (Illinoian)  6 

Blue  till  (Illinoian) 33 

Sand  and  peaty  material,  underlain  by  a  fine  gravelly  sand  (alluvial  and  Kansan) 50 

Limestone 12 

Depth 131 

It  is  probable  that  the  Illinoian  drift  extends  to  the  peaty  material  at  a 
depth  of  70  feet,  for  the  well  stands  upon  probably  the  most  elevated  point 
on  the  ridge  in  this  county,  at  a  level  nearly  70  feet  above  the  outer  border 
plain.  A  neighboring  well  in  the  same  section,  on  the  farm  of  F.  Timpe, 
penetrated  about  12  feet  of  loess-like  silt  and  slightly  pebbly  yellow  clay, 
at  which  depth  a  very  calcareous,   sandy,   yellow  till  is   entered.      This 


54 


THE  ILLINOIS  GLACIAL  LOBE. 


changes  to  a  blue  till  within  a  few  feet.  A  large  amount  of  wood  was 
in  the  blue  till  near  the  bottom  of  the  well,  at  a  depth  of  25  to  30  feet. 
The  wood,  however,  is  incorporated  in  the  till  in  the  same  manner  as 
bowlders  or  pebbles,  and  does  not  indicate  a  soil  horizon.  The  well  appar- 
ently terminated  in  the  lUinoian  drift. 

On  the  plain  east  of  this  ridge  a  black  soil  (Yarmouth),  which  separates 
the  Illinoian  sheet  from  the  underlying  drift,  has  been  noted  in  wells  at  the 
following  depths: 

Depth  to  blacl-  soil  (Yarmouth)  in  wells  on  the  plain  near  jDenmarTc,  loica. 


C.  A.  Flohrer,  sec.  10,  T.  69,  R.  5  W 

"\V.  Hawkins,  see.  13,  T.  69,  R.  .5  W 

E.  Newton,  sec.  24,  T.  69,  R.  5  W 

C.  H.  Burton  estate,  sec.  25,  T.  69,  R.  5  W 
Thomas  Saunderson,  sec.  .S5.  T.  69,  R.  5  W 

Benj.  Krehbiel,  sec.  36,  T.  69,  R.5  W 

Mr.  Holstein,  sec.  30,  T.  69,  R.  4  W 

5.  Van  Tuyl  estate,  sec.  30,  T.  69,  R.  1  W . 

6.  B.  Brackett.  Denmark 

James  Conaro,  Denmark 

William  Blackiuton,  Denmark 

Dr.  William  Sloat,  Denmark 

Public  well,  Denmark 


Altitude 
A.T. 


Depth. 


Feet. 
725 
715 
725 
720 
720 
720 
725 
715 
700 
700 
700 
700 
700 


Feet. 
30-32 
16-20 
35-40 
30-35 
20-22 
35-40 
45-48 
35-37 
20-26 
19-24 
26 
25 
20-30 


The  wells  at  Mr.  Flohrer's  and  Mr.  Hawkins's  pass  through  several  feet 
of  ash-gray  clay,  apparently  a  subsoil,  immediately  below  the  black  soil. 
Exjiosures  on  ravines  in  this  part  of  the  county  sustain  this  interpretation 
of  soil  and  subsoil.     The  Van  Tuyl  well  has  the  following  series  of  beds: 

Section  in  tcell  on  S.  Van  Tuyl  estate,  near  T>enmarl;,  loira. 

Feet. 

Yellow  silt  or  loess,  slightly  calcareoiis  and  containing  a  few  small  pebbles  near  base  (lowan) 7 

Brownish-yellow  clay,  with  few  pebbles  anil  but  slightly  calcareous  (Illinoian^ 10 

Brownish-yellow  till,  i>ebbly  and  calcareous  (Illinoian) 8 

Blue  clay,  with  few  pebbles  (Illinoian) 10 

Blaik  mucky  soil,  with  wood  (Yarmouth) 2 

Brownish-yellow  till  (Kansan) 12 

Hard  blue  till  (Kansan) 6 

Limestone 4 

Total 59 


STRUCTUEE  OF  THE  DEIPT  BOEDER.  55 

The  well  at  Dr.  Sloat's  penetrates  the  following  beds: 

Section  in  toell  of  Dr.  William  Sloat,  in  Denmarli,  loica. 

Feet. 

Yellow  Bilt  or  loess  (lowan) 6 

Brownish-yellow  clay,  slightly  pebbly  (lUinoiau) 20 

Mucky  clay,  largely  of  gray  color  and  containing  a  few  small  pebbles  (Yarmouth,  and  possibly 

Kansau) 15 

Brownish-j'ellow  till  (Kansan) 10 

Dark- blue  till,  with  beds  of  saud  yielding  water 5 

Total  depth 56 

The  well  at  Mr.  Conaro's  was  carefully  observed  by  the  writer,  during 
its  excavation,  and  has  the  following  section: 

Section  in  icell  of  James  Gonaro,  in  Denmark,  lotca. 

Feet. 

Yellow  silt  or  loess  (lowan) 9 

Brown  clay,  not  calcareous,  with  occasional  pebbles,  3  inches  or  less  in  diameter  (Illinoian) 10 

Soil  and  grayish  subsoil,  slightly  pebbly,  not  calcareous  (Yarmouth) 5 

Brownish-yellow  till,  leached  for  6  feet  at  top,  remainder  very  calcareous  (Kansan) 25 

Total  depth 49 

At  Mr.  Blackiuton's  well,  which  was  also  personally  observed  during 
its  excavation,  the  upper  20  feet  is  a  thoroughly  leached  clay;  the  remainder 
is  calcareous  till  of  brownish-yellow  color,  Avhich  includes  thin  beds  or 
pockets  of  sand  and  extends  to  the  rock,  which  is  struck  at  a  depth  of  54 
feet.  In  this  connection  it  may  be  remarked  that  several  of  the  wells  in 
the  vicinity  of  Denmark  penetrate  yellow  till  below  the  Illinoian  drift  sheet 
to  a  depth  of  25  or  30  feet,  there  being  little  or  no  blue  till  above  the  rock. 
At  the  public  well,  however,  a  blue-black  till  occurs  at  52  to  63  feet.  Expo- 
sures on  ravines  both  north  and  south  of  the  village  also  have  a  dark  blue- 
black  till  beneath  the  yellow  at  a  level  15  or  20  feet  below  the  top  of  the 
Kansan  sheet  of  drift.     Possibly  this  is  pre-Kansan  till. 

On  the  bluff  north  of  Fort  Madison  a  well  made  at  the  residence  of 
Mrs.  Heitz  reached  a  depth  of  315  feet  without  entering-  rock.  Blue  till  was 
entered  at  27  feet,  which,  with  the  exception  of  a  thin  sand  bed,  presents  a 
solid  mass  260  feet  in  thickness.  Beneath  this  till,  in  the  lower  26  feet  of 
the  well,  there  is  a  cemented  gravel.  Exposures  in  neig'hboring  ravines 
indicate  that  the  Illinoian  drift  sheet  on  the  bluffs  at  Fort  ]\Iadison  is  not 
more  than  20  feet  in  depth.  The  thick  bed  of  blue  till  passed  through 
in  the  well  is  apparently  as  old  as  the  Kansan,  and  includes  perhaps  an 
earlier  drift  sheet.     Along  the  Mississippi  bluff  above  Fort  Madison  there 


56  THE  ILLINOIS  GLACIAL  LOBE. 

are  exposures  of  drift  180  feet  in  height.  The  upper  .50  or  60  feet  consists 
of  alternations  of  till  with  sand  or  gravel,  and  is  referred  mainly  to  the 
Kansan.  The  remaining  120  feet  is  a  nearly  solid  mass  of  dark-blue  till, 
which  is,  however,  characterized  by  stony  parts  that  give  it  the  appearance 
of  being  interbedded  with  gravel  and  cobble.  These  bands  of  stony  material 
are  very  nearly  horizontal.  It  is  not  certain  that  this  should  be  referred  to 
the  Kansan;  possibly  it  is  pre-Kansan.  Many  bowlders  are  accumulated 
along  the  base  of  this  bluff.  A  strip  covered  with  these  bowlders,  having 
a  length  of  8  rods  and  a  width  of  3  rods,  was  carefully  exajnined.  It  in- 
cluded 107  bowlders,  with  an  average  diameter  of  about  3  feet.  The  largest 
three  exceed  6  feet  in  diameter;  the  smallest  included  in  the  count  were  at 
least  a  foot  in  diameter.  Upon  classifying  the  bowlders  it  was  found  that 
red  granite  greatly  predominates,  there  being  85  specimens.  Of  the  gray 
or  dark-colored  granite  only  6  were  found.  The  greenstones  are  repre- 
sented by  10  specimens.  The  two  remaining  specimens  were  limestone. 
About  one-fourth  of  the  bowlders  were  glaciated  on  the  sides  exposed  to 
view;  probably  inany  others  are  glaciated  on  the  under  side.  The  jjro- 
portion  of  red  granite  is  exceptionally  large  for  this  region,  though  it  is 
probable  that  at  least  half  the  bowlders  are  of  this  class.  These  bowlders 
are  probably  largely  from  the  dark-blue  till. 

The  artesian  wells  in  the  Mississippi  Valley  at  Fort  Madison  enter  rock 
at  a  level  about  135  feet  below  low  water  in  the  Mississippi,  or  at  about 
365  feet  above  tide.  The  drift  is  mainly  blue  till,  such  as  is  exposed  in  the 
neighboring  bluff.  It  is  older  than  the  Illinoian,  and  possibly  is  pre-Kansan. 
This  blue  till  is  covered  to  a  depth  of  10  to  40  feet  by  alluvial  sand,  which 
in  places  extends  to  near  the  level  of  the  river  bed. 

The  artesian  well  on  the  Mississippi  bluff  at  Mont  Clare,  about  12 
miles  southwest  of  Fort  Madison,  penetrated  305  feet  of  drift.  It  is 
reported  to  be  mainlj^  through  clay  for  a  depth  of  250  feet,  beneath  which 
there  is  sand  extending  to  the  rock.  This  well,  it  should  be  noted,  stands 
just  outside  the  limits  of  the  Illinoian  drift.  The  drift,  therefore,  like  that 
at  Fort  Madison,  belongs  to  an  earlier  sheet  than  the  Illinoian. 

The  Illinoian  drift  ])robably  extends  to  the  western  limits  of  the  upland 
in  Hancock  County,  Illinois,  tln-oughout  the  entire  length  of  the  county. 
The  drift,  however,  can  not  be  referred  entirely  to  the  Illinoian  invasion,  for 
there  are  southeastward-bearing  strife  in  the  western  part  of  this  county. 


STKUOTUEE  OF  THE  DRIFT  BORDEE.  57 

which  indicate  that  the  earlier  ice  invasion,  from  the  Iowa  side,  crossed  the 
Mississippi  into  western  lUinois.  Instances  of  a  soil  between  till  sheets  have 
also  been  found  in  this  county,  as  in  the  counties  of  southeastern  Iowa  just 
discussed,  and  this  soil  is  referred  to  the  Yarmouth  interglacial  interval. 
The  distance  to  which  the  lUinoian  sheet  overlapped  the  earlier  one  is  not 
known.  It  is  probable  that  the  heavy  deposits  of  drift  found  in  central  and 
southern  Hancock  Count)-  should  be  largely  referred  to  the  earlier  invasion. 
A  well  made  by  William  McCuen  on  the  east  slope  of  the  terminal 
rido-e  of  the  lUinoian  drift,  about  4  miles  south  of  Hamilton,  has  the  fol- 
lowino'  section : 

a 

Section  in  icell  of  William  McCrien,  about  4  miles  south  of  Hamilton,  Illinois. 

Peet. 

Yellow  silt  or  loess  (lowan) '-' 

Soil  auil  groy  subsoil  grailing  downward  into  a  pale  till  (Sangamon  and  Illinoian) 22 

Blue  till  (probably  Illinoian) ^ 

Peaty  muck  witb  wood  (probably  Yarmouth) ^ 

Pebbly  clay  of  bluish  color  (probably  Kansan) 38 

Total  depth - - - "'^ 

Mr.  McCuen  reports  that  other  wells  in  the  neighborhood  have  pene- 
trated a  similar  buried  peat.  It  seems  probable  that  this  peat  is  at  the  base 
of  the  Illinoian  sheet,  though  it  may  possibly  be  interbedded  with  other 

deposits. 

From  near  Carthage  southward  past  Stillwell  there  is  a  filled  valley 
whose  position  is  revealed  by  the  deep  wells,  the  filling  being  so  complete 
that  there  are  no  surface  indications  of  the  course.  The  artesian  wells  at 
Carthage  penetrate  214  feet  of  drift,  and  several  wells  between  Carthage 
and  Stillwell  reach  a  depth  of  nearly  200  feet  without  entering  rock,  and 
one  a  depth  of  220  feet.  A  well  at  Owen's  mill  in  Stillwell  enters  rock  at 
207  feet.  As  the  surface  elevation  at  these  wells  is  nearly  200  feet  above 
the  Mississippi  River,  those  which  strike  rock  enter  it  at  about  river  level. 
Probably  the  deepest  part  of  this  filled  valley  is  cut  to  a  much  lower  depth, 
for  the  rock  floor  of  the  preglacial  Mississippi  is  100  feet  or  more  below  the 
level  of  low  water  in  the  stream.  In  nearly  all  these  deep  wells  the  drift 
is  mainly  a  blue  till  similar  to  that  exposed  in  the  Mississippi  bluff  near 
Fort  Madison,  and,  like  that  near  Fort  Madison,  is  probably  older  than  the 
Illinoian.  In  some  wells  the  blue  till  is  entered  at  a  depth  of  onl}'  20  to 
25  feet,  but  in  the  majorit}-  it  is  struck  at  35  to  40  feet. 


58  THE  ILLINOIS  GLACIAL  LOBE. 

On  the  poi-tion  of  the  ^Mississippi  bhiff  above  Hamihon  the  drift  is 
only  20  or  30  feet  in  (le])th  and  is  largely  of  sandy  constitution.  It  seems 
probable  that  some  modification  of  the  glacial  drift  has  resulted  through 
drainage  connected  with  the  melting  of  the  Illinois  glacial  lobe.  The  evi- 
dences of  a  delta-like  filling  at  the  lower  end  of  the  Des  Moines  rapids,  near 
Warsaw,  are  discussed  on  another  page. 

In  Adams  Countv  the  Illinoian  sheet  has  a  series  of  ridges  developed 
near  the  border.     The  outermost  one  lies  but  a  short  distance  east  of  the 
Mississippi  bluff,  and  is  interrupted  by  wide  gaps  through  which  the  streams 
find  passage  into  the  Mississippi.     The  inner  ridges  occupy  a  portion  of  the 
divide  between  the  lUinois  and  Mississippi  rivers  in  the  central  and  south- 
eastern part  of  the  county.     These  ridges  differ  greatly  in  structure  from 
point  to  point.     The  portion  of  the  outer  ridge  north  from  Bear  Creek  is 
composed  largelj'  of  ordinary  brownish-yellow  till,  but  throughout  its  con- 
tinuation south  of  Bear  Creek,  from  near  Mendon  southward  past  Eubanks, 
it  contains  a  large  amount  of  sand  and  gravel.     The  upper  30  or  40  feet, 
however,,  is  often  of  clayey  constitution,  and  this  included,  probably,  the 
entire  Illinoian  sheet  as  it  extends  about  to  the  level  of  the  base  of  the  ridge. 
In  places  the  sand  and  gi-avel  beneath  this  ridge  is  thought  to  be  of  pregla- 
cial  age,  and  it   seems  not  improbable  that  the  portions  which  contain 
Canadian  rocks  or  other  erratics  may  be  composed  in  large  part  of  slightly 
modified  preglacial  material.    The  material  thrown  out  from  wells  at  Mendon 
was  carefully  examined  and  was  found  to  be  a  quartz  sand,  of  orange  color, 
entirely  free  from  calcareous  material.     But  exposures  of  a  similar  sand 
near  Eubanks  were  found  to  include  occasional  Canadian  rocks  in  their 
upper  portion,  as  if  the  sand  had  been  worked  upon  by  the  ice  sheet  and 
redeposited,   together    with  some    of   the   material    contained   in  the  ice. 
Upon  following  this  ridge  southeastward  to  IMill  Creek  a  change  to  till  is 
found,  and  the  valley  of  Mill  Creek,  at  the  point  where  the  ridge  crosses, 
is  shown  by  wells  to  have  been  filled  to  a  depth  of  150  feet  or  more  with 
a  clayey  deposit  which  from  description  appears  to  be  till,  there  being 
numerous  pebbles  incorporated  in  it.     A  well  made  at  the  residence  of  Mrs. 
Ihrig,  on  the  west  bluff  of  Mill  Creek,  in  sec.  15,  T.  2  S.,  R.  8  W.,  reached 
a  depth  of  155  feet  without  encountering  rock.     It  was  mainly  through 
clay,  except  a  few  feet  of  sand  at  the  l)ottom.     A  well  on  the  east  bluff  of 
the  creek,  in  section  12  of  the  same  township,  is  200  feet  in  depth  and  is 


STRUCTURE  OF  THE  DRIFT  BORDER.  59 

thought  to  have  entered  rock  only  40  feet;  it  also  is  reported  to  have  been 
largely  through  clay. 

On  the  elevated  district  near  Payson  wells  penetrate  alternations  of  clay 
and  gravel  to  a  depth  of  60  feet  or  more.  A  well  made  by  Mr.  Barnard, 
1  mile  west  of  Payson,  after  penetrating  60  feet  of  clay  and  gravel,  entered 
a  red  clay,  apparently  formed  from  the  limestone  which  underlies  that 
region.  In  some  places  the  gravelly  beds  of  the  drift  seem  to  rest  directly 
upon  undecayed  rock  sui-face. 

A  small  drift  ridge  is  traceable  southeastward  from  the  village  of  New- 
ton (Adams  post-office),  on  which  wells  have  been  sunk  to  a  depth  of  75  or 
100  feet  without  entering-  rock.  The  town  well  at  Newton  is  reported  to  be 
mainly  tlxi'ough  clay,  with  a  few  feet  of  gravel  at  bottom.  A  well  at  Mrs. 
Wittemeyer's,  on  the  crest  of  the  ridge,  about  a  mile  southeast  of  Newton, 
reached  a  depth  of  82  feet  and  apparently  j)assed  through  a  buried  soil 
between  sheets  of  till.  Exposures  of  a  buried  soil  are  to  be  seen  near  the 
level  of  the  base  of  the  ridge  in  the  road  leading  south  from  Mrs.  Wittemeyer's, 
in  sec.  35,  T.  2  S.,  R.  7  W.,  but  at  that  place  it  is  underlain  by  sandy  gravel. 
The  following  is  a  section  of  the  well  as  reported  by  the  owner: 

Section  in  icell  at  Mrs.  Wittemeyer's,  a  mile  southeast  of  Newton,  Adams  County,  Illinois. 

Feet. 

Yellow  clay  wltliout  pebbles  (lowau) 10 

Pebbly  yellow  clay  (lUinoian). 30 

Mucky  gray  clay  (probably  a  Yarmouth  soil) 7 

Sandy  and  pebbly  clay  grading  downward  into  sand  (Kansan) 35 

Total  depth 82 

On  the  plain  northeast  of  this  ridge,  from  the  village  of  Burton  east- 
ward to  Liberty,  the  ravines  expose  a  yellowish  gummy  clay,  containing 
few  pebbles  to  a  depth  of  50  feet,  which  is  referred  to  the  Illinoian.  There 
do  not  appear  to  be  large  pebbles  or  bowlders  in  such  number  as  usually 
occur  in  the  typical  till. 

Farther  south,  in  the  vicinity  of  Plainville  and  eastward  from  that 
village,  the  ravines  expose  a  large  amount  of  cherty  gravel  and  cobble  in 
the  lower  part  of  the  drift,  but  the  upper  part,  to^a  depth  of  20  feet  or 
more,  is  usually  a  clay  containing  but  few  pebbles.  This  phase  of  the 
drift,  as  noted  below,  extends  across  Pike  County  and  characterizes  the 
extreme  border  of  the  Illinoian  sheet.  It  is  probable  that  the  chert  is  a 
residual  product  from  the  chert}^  limestones  of  that  locality. 


60  THE  ILLINOIS  GLACIAL  LOBE, 

Along  the  divide  between  the  IlUnois  and  Mississippi  rivers,  from  the 
southeast  corner  of  the  county  northwestward  to  the  vicinity  of  Liberty, 
there  is  a  ridge  made  up  in  part  of  till  and  in  part  of  sand  and  gravel.  In 
the  vicinity  of  Kingston  (Fairweather  post-oifice)  wells  along  the  crest  of 
the  ridge  have  reached  a  depth  of  90  feet  without  entering  rock.  The 
ravines  near  this  village  expose  an  ash-gray  soil  (Sangamon)  below  the 
loess,  and  beneath  this  a  brown  gummy  clay,  slightly  pebbly,  with  occa- 
sional bowlders,  which  is  probably  of  lUinoian  age.  This  clay  is  seldom 
more  than  15  feet  in  depth,  and  is  underlain  by  sand  containing-  few 
pebbles.  In  the  ^^cinity  of  Beverly  the  sand  is  absent  and  a  blue  till 
appears  below  the  brown  g-ummy  clay.  A  well  at  J.  Sykes's,  about  a  half 
mile  east  of  Beverly,  is  thought  to  have  entered  preglacial  sand  in  its  lower 
part.  The  well  is  an  excavated  one,  6  feet  in  diameter,  and  several  wagon 
loads  of  the  sand  were  thrown  out  on  the  dump,  where  excellent  opportunity 
for  comparing  it  with  the  glacial  dejaosits  was  afforded.  An  examination  of 
these  deposits,  supplemented  by  information  furnished  by  Mr.  Sykes,  enables 
the  writer  to  present  the  following  section: 

Section  in  icell  of  J.  SyTtes,  a  half  mile  east  of  Beverly,  Adams  Goimfij,  Illinois. 

Peet. 

Loess  and  gummy  brown  clay  with  few  pebbles 35 

Gray  sand 3 

Blue  till,  very  stony,  with  largo  bowlders  and  fragments  of  wood 27 

Gray  sand  and  gravel,  calcareous 5 

Orange-colored  quartz  sand,  noncalcareous 14 

Total  depth 84 

This  well  is  located  in  an  elevated  part  of  the  county,  about  360  feet 
above  the  Mississippi  River.  A  similar  deposit  of  sand  was  found  in  a  well 
in  the  village  of  Beverly  at  a  depth  of  56  to  76  feet,  or  very  nearly  the 
same  elevation  above  tide  as  the  well  at  Mr.  Sykes's,  the  well  mouth  being 
on  ground  16  or  20  feet  lower  than  the  Sykes  well.  The  immerous  ravines 
leading  eastward  from  this  ridge  toward  McKees  Creek  may  afford  expo- 
sures of  the  sand,  but  none  were  noted  by  the  writer. 

Along  the  portion  of  the  Illinois-Mississip])i  divide  between  Liberty  and 
Fowler  the  drift  is  very  thick  and  its  lower  part  is  of  peculiar  constitution. 
Well  drillers  and  several  of  the  residents  report  that  after  a  depth  of  about 
30  feet  is  reached  a  blue-black  clay,  with  sand  partings  and  with  much  wood, 
is  entered,  which  extends  down  nearly  <>r  (piite  to  the  limestone  underlving 


STRUCTURE  OF  THE  DRIFT  BORDER.  61 

that  region.  The  wi-iter  had  opportunity  to  examine  the  material  thrown 
out  of  a  well  at  the  residence  of  James  Loveless,  in  see.  34,  T.  1  S.,  R.  7  W., 
and  found  it  to  be  a  blue-black  silt,  very  calcareous,  and  containing  onlv 
minute  pebbles  and  sand  grains.  Several  specimens  of  wood  from  this  silt 
which  were  inspected  by  the  writer  also  carried  a  coating  of  similar  silts. 
Above  the  silt  there  is  ordinary  till,  except  a  thin  coating  of  loess  at  the 
surface  and  pockets  or  thin  beds  of  sand  or  gravel  or  silty  clay  in  the  till. 
In  Mr.  Loveless's  well  the  following-  section  appears: 

Section  in  well  of  James  Loveless,  between  Liberty  and  Foicler,  Adams  County,  Illinois. 

Feet. 

Yellow  silt  or  loess 6 

Ashy  soil  and  subsoil  containing  a  few  small  pebbles 12 

Calcareous  yellow  till 22 

Gray  gummy  clay,  resembling  soil,  noncalcareous 2 

Calcareous  yellow  till 18 

Blue-black  silt,  very  calcareous 2 

Total  depth g2 

At  the  county  infirmary,  in  sec.  11  of  the  same  township  (T.  1  S., 
R.  7  W.),  a  well  struck  rock  at  a  depth  of  165  feet.  The  lower  100  feet  of 
the  drift  is  a  blue  silt  apparently  similar  to  that  in  Mr.  Loveless's  well.  A 
shallower  well  at  the  infirmary  obtained  water  in  sand  and  gravel  at  a 
depth  of  40  to  58  feet.  A  well  on  the  farm  of  Mr.  Henr}^,  in  sec.  3,  within 
a  mile  of  the  infirmar}-,  has  a  section  similar  to  that  of  the  deep  infirmary 
well  and  entered  rock  at  160  feet. 

Several  of  the  wells  in  the  village  of  Libert}^  penetrate  a  similar  blue- 
black  silt,  entering  it  at  about  60  feet  and  continuing  in  one  case  to  a  depth 
of  90  feet  Avithout  entering  rock.  In  the  vicinity  of  this  village,  however, 
rock  is  occasionally  entered  at  a  depth  of  50  feet  or  less,  and  only  2  miles 
east  of  the  village  and  at  a  slightly  higher  elevation  rock  is  struck  at  only 
25  feet. 

There  is  a  low  ridge  leading  from  the  village  of  Coatsburg  eastward  5 
or  6  miles  on  which  the  wells  occasionally  enter  a  blue-black  silt  similar  to 
that  found  on  the  district  just  described.  A  well  at  the  mill  in  Coatsburg  is 
reported  to  be  mainly  through  pebbly  clay  to  a  depth  of  65  feet,  beneath 
which  there  is  a  blue  clay  with  sand  jiartings  and  wood  embedded,  which 
was  penetrated  30  feet  Avithout  entering  rock.  A  boring  for  coal  a  mile  east 
of  Coatsburg  is  discussed  in  the  Geology  of  Illinois  because  of  the  occur- 
rence of  this  blue-black  material  in  the  lower  portion  of  the  drift,  which  is 


62  THE  ILLINOIS  GLACIAL  LOBE. 

thfere  considered  a  " post-Tertiaiy  soil"  older  than  the  drift  proper,  and 
formed  xmder  very  different  conditions.  The  following  is  the  section  there 
published: 

Section  in  a  horinfj  for  coal,  a  mile  eastofCoatsburg,  Adams  County,  Illinois. 

Feet. 

Soil  and  yelloTv  clay 6 

Blmsh-colored  clay  and  gravel 15 

Clay  with  large  lio  wlders 40 

Black  soil ■ 2+ 

Clay  (stratified) 6 

Very  tough  blue  clay 20 

Rock  entered  at 119 

It  seems  not  improbable  that  the  silt  under  the  till  of  central  Adams 
Count}^  is  attributable  to  ponded  waters  held  in  front  of  the  Keewatin  ice 
sheet  in  the  Kansan  stage,  for  that  ice  sheet  apparently  crossed  the  Missis- 
sippi into  Illinois  near  Hannibal,  Missouri,  and  covered  the  lower  courses  of 
its  eastern  tributaries. 

In  Pike  County  typical  till  has  been  seen  at  but  few  points.  The 
several  drift  ridges  which  traverse  the  county  are  composed  largely  of  clay 
and  sand  in  which  only  a  few  small  pebbles  occur.  There  is,  however,  on 
the  borders  of  Hadley  Creek,  in  the  northern  part  of  the  county  and  the 
adjacent  portion  of  Adams  County,  considerable  waterworn  chert  in  the 
base  of  the  drift.  This  chert  is  apparently  a  residuary  product  from 
the  decay  of  cherty  limestone  in  that  region,  but  it  was  worked  over  to 
some  extent  by  the  ice  sheet  and  its  associated  waters,  and  this  has  resulted 
in  the  introduction  into  the  chert  of  occasional  bowlders  and  smaller  stones 
of  distant  derivation,  as  well  as  the  wearing  and  rounding  of  the  chert  frag- 
ments. These  chert  beds  are  in  places  10  or  15  feet  thick.  They  usually 
present  the  appearance  of  gravel  beds,  there  being  very  little  clay  present. 
Exposures  were  found,  however,  east  and  southeast  of  Baylis,  on  the  west 
side  of  Bay  Creek,  in  which  a  large  amount  of  clay  is  mingled  with  the 
chert  and  other  stony  material.  In  the  southwest  part  of  the  count}-,  which 
appears  to  have  been  but  slightly  glaciated,  if  at  all,  the  chert  beds  remain 
intact  at  the  surface  of  the  limestone.  Quarries  along  the  east  bluff  of  the 
Mississippi  afford  good  exposures. 

A  few  well  sections  and  hillside  sections  obtained  in  the  vicinity  of  the 
drift  border  are  here  given  to  illustrate  and  make  clearer  the  above  state- 
ments. 


STRUCTURE  OF  THE  DRIFT  BORDER.  Q  ] 

Hillside  exposures  on  the  line  of  Pike  and  Adams  counties,  in  R.  5  W., 
have  a  bed  of  cherty  g'ravel  with  occasional  Canadian  rocks  resting  on  the 
sui'face  of  the  limestone,  and  covering-  it  to  a  depth  of  5  to  15  feet.  Above 
this  gravel  there  is  usually  40  or  50  feet  of  clay  containing  very  few  pebbles. 
The  deeper  exposures  show  it  to  be  of  a  gray  color,  but  the  surface  portion 
is  yellow.  Capping  this  clay  is  a  thin  deposit  of  loess,  separated  in  places 
fi'om  the  clay  by  a  gray  or  ashy  (Sangamon)  soil. 

At  the  residence  of  A.  Hill,  2  miles  north  of  Baylis,  on  the  crest  of 
tlie  main  drift  ridge,  a  freshly  excavated  w  ell  was  found  to  have  the  follow- 
ing section: 

Section  in  well  of  A.  Hill,  3  miles  north  of  Baylis,  Pike  County,  Illinois. 

Feet. 

Bro^n  clay  with  few  pebbles 25 

Graj'  sand 10 

Gray  clay,  nearly  free  from  pebbles 33 

Total  depth 68 

At  Baylis  an  experimental  boring  for  water  reached  a  depth  of  90  feet 
without  entering  rock  or  penetrating  coarse  material  of  any  kind.  The 
upper  30  feet  consisted  of  5^ellow  clay  and  the  remainder  of  fine  sand. 
This  well  is  located  on  the  crest  of  the  main  ridge,  at  an  altitude  about  400 
feet  above  the  Mississippi  River.  East  and  south  from  Baylis  numerous 
exposures  are  found  in  which  a  pebbly  brown  claj^  underlies  the  loess  at  a 
depth  of  8  or  10  feet. 

In  the  northeast  part  of  the  county,  in  the  vicinity  of  New  Salem  and 
Griggsville,  and  thence  north  to  the  county  line,  the  wells  and  natural 
exposures  reveal  only  a  small  amount  of  stonj"  clay,  the  greater  part  of  the 
drift  being  nearly  pebbleless.  Rock  is  often  entered  at  30  or  40  feet,  or 
even  less  depth. 

In  the  vicinity  of  Time  the  ravines  expose  a  pebbleless  clay,  probably 
a  ]Dhase  of  the  loess,  to  a  depth  of  20  feet  or  more,  beneath  which  there  is  a 
slightly  pebbly  brown  clay.  The  village  well  at  Time  reached  the  bottom 
of  this  brown  clay  at  a  depth  of  50  feet,  and  then  penetrated  20  feet  of  blue 
clay  resembling  putty,  and  terminated  at  a  depth  of  70  feet  without  entering 
rock.  At  J.  E.  Dinsmore's  farm,  south  of  Time  (sec.  26,  T.  6  S.,  R.  3  W.), 
a  well  60  feet  in  depth  is  largely  through  typical  till,  exposures  of  which 
are  to  be  seen  in  neighboring  ravines.  Mr.  Dinsmore  made  a  well  in 
sec.  23,  in  a  ravine  30  or  40  feet  below  the  level  of  the  upland  plain,  which 


64  THE  ILLINOIS  GLACIAL  LOBE. 

penetrated  40  feet  of  nearly  pebbleles.s  brown  clay,  beneath  which  there  is 
a  black  muck  5  or  (i  feet  in  depth  which  rests  upon  a  red  clay,  apparently 
a  residuary  product  from  the  decay  of  limestone. 

East  of  Bay  Creek,  in  T.  6  S.,  R.  2  W.,  wells  along  the  oiiter  di-ift 
ridge  frequently  reach  a  depth  of  50  feet,  and  occasionally  80  feet,  without 
entering  rock.  From  descriptions  of  the  matei'ial,  it  is  probable  that  ordinary 
till  is  penetrated,  but  no  exposures  were  found.  The  loess  in  that  locality 
is  about  20  feet  in  depth. 

From  Pike  County  the  drift  border  passes  to  the  east  side  of  the 
Illinois.  A  typical  till  constitutes  the  greater  ]oart  of  the  di'ift  exposed  in 
ravines  along  that  side  of  the  river  in  Scott,  Greene,  and  Jersey  counties. 
The  loess  on  the  river  bluff  is  usually  20  or  30  feet  in  depth,  but  within  8 
or  10  miles  east  of  the  river  it  decreases  to  10  feet  or  less.  The  di-ift  forms 
a  deposit  pi-obably  50  feet  in  average  depth  at  the  east  border  of  the  Illinois 
Valley,  but  immediately  west  of  the  Illinois,  in  southern  Pike  and  in  Calhoun 
County,  there  is  scarcely  a  trace  of  drift. 

There  are  several  knolls  and  ridges  of  drift  a  few  miles  back  from  the 
drift  border  in  Grreene  and  Jersey  counties,  but  no  accurate  well  sections  or 
other  exposures  of  their  structure  were  obtained.  The  descriptions  given 
by  residents,  however,  indicate  that  they  are  composed  larg-ely  of  clay. 

In  Madison  County  typical  till  is  found  along-  the  east  blutf  of  the 
Mississippi  throughout  the  entire  width  of  the  county,  as  well  as  at  points 
farther  east.  At  the  immediate  border  of  the  valley  there  is  a  deposit  of 
loess  30  to  50  feet  in  depth,  but  Avithin  10  miles  back  from  the  bluff  the 
thickness  decreases  to  10  feet  or  less.  The  till  is  usually  25  to  50  feet  in 
depth,  and  where  thickest  is  of  a  blue  color  near  the  bottom. 

Opposite  Madison  County,  in  St.  Louis  Countv,  Missouri,  north  from 
the  c-ity  of  St.  Louis,  deposits  of  waterworn  material  of  glacial  derivation 
underlie  the  loess  for  a,  few  miles  back  from  the  bluff  of  the  river.  These 
deposits  contain  a  few  bowlders,  1  to  2  feet  in  diameter,  as  well  as  cobble  and 
gravel.  The  rock  constituents  appear  to  be  different  from  those  of  the  drift  in 
Madison  County,  Illinois,  there  being  present  considerable  material  apj^ar- 
ently  brought  down  from  the  exposures  of  the  sandstone  and  limestone  of 
Silurian  age  on  the  borders  of  the  Mississippi  in  Calhoun  Countv,  Illinois, 
and  Lincoln  County,  jMissouri.  The  presence  of  this  material  suggests 
water  rather  th;iii  ice  transjjortation,  and  it  remains  an  open  question  whether 


STEUCTUEE  OF  THE  DRIFT  BOEDEE.  65 

the  ice  sheet  reached  into  northern  St.  Louis  County  from  the  Ilhuois  side 
of  the  river. 

On  the  east  bluff  of  the  Mississippi  below  East  St.  Loiiis  only  a  small 
amount  of  glacial  drift  has  been  found  beneath  the  loess  deposits,  which 
there  cap  the  bluff  to  a  depth  of  30  to  60  feet  or  more.  The  drift  usually 
consists  of  a  thin  bed  of  stony  material,  but  in  some  of  the  recesses  of  the 
bluffs  and  in  ravines  exposures  of  nearly  pebbleless  clay  are  occasionally 
seen.  Some  of  these  exposures  near  Columbia,  in  Monroe  County,  reach  a 
depth  of  40  to  50  feet.  An  occasional  bowlder  a  foot  or  more  in  diameter 
is  found  in  these  deposits,  but  stones  are  very  rare  compared  with  their 
number  in  the  typical  till,  such  as  is  exposed  in  the  east  bluff  of  the  Missis- 
sippi above  East  St.  Louis.  It  is  probable  that  the  ice  sheet  extended  as 
far  west  as  the  east  bluff  of  the  Mississippi  in  St.  Clair,  Mom-oe,  and  Ran- 
dolph counties,  but  the  deposits  there  are  very  much  thinner  than  in  drift 
ridges,  discussed  later,  which  traverse  the  eastern  portion  of  these  counties, 
and  which  perhaps  mark  an  ice  margin  at  a  somewhat  later  period  than  that 
of  the  maximum  extension. 

The  portion  of  the  drift  border  in  southern  Illinois,  on  the  slopes  of 
the  elevated  rock  ridge  in  Jackson,  Williamson,  and  Saline  counties,  con- 
tains typical  till,  but  the  deposit  is  seldom  more  than  20  or  25  feet  in  depth. 
In  one  instance,  however,  a  well  in  the  southwest  township  of  Williamson 
County  was  found  to  have  reached  a  depth  of  70  feet  without  entering  rock. 
The  distance  to  rock  is  also  great  in  the  ^dcinitj"  of  Murphy sboro,  in  Jack- 
son County.  The  wells  and  borings  for  coal  often  reach  a  depth  of  100 
feet,  and  occasionally  130  feet,  before  entering  rock.  The  di-ift  is  reported 
to  be  largely  sandy  material,  but  the  upper  portion,  exposed  to  a  depth  of 
50  feet  by  Big  Muddy  River,  is  mainly  clsij  containing  but  few  pebbles. 

On  the  borders  of  the  Ohio  Valley,  in  Grallatin  County,  Illinois,  there 
is  a  belt  of  sandy  material  several  miles  in  width  which  is  not  referred  with 
certainty  to  glacial  deposition.  Back  of  this  a  typical  till  sets  in,  which  is 
exposed  in  ravines  beneath  8  or  10  feet  of  loess.  Wells  usually  reach  the 
bottom  of  the  drift  at  20  or  30  feet,  but  one  2^  miles  north  of  Ridgway 
reached  a  depth  of  98  feet  without  entering  rock,  and  another  3  miles  west 
of  Ridgway  a  depth  of  75  feet.  In  the  Ohio  Valley  at  Shawneetown  a 
boring  for  gas  and  oil  penetrated  112   feet  of  allu^aal  and  other  deposits 

MON  XXXVIII 5 


66  THE  ILLIISrOIS  GLACIAL  LOBE. 

before  entering  rock  This  appears  to  be  outside  the  glacial  boundary, 
but  the  material  penetrated  is  probably  derived  from  glacial  deposits 
brought  down  the  valley. 

In  southwestern  Indiana  the  drift  in  the  vicinity  of  the  glacial  bound- 
aiy  frequently  reaches  a  depth  of  more  than  100  feet  in  the  valleys;  but 
on  the  uplands  it  rarely  exceeds  40  feet,  and  is  usually  but  10  or  20  feet. 
As  a  rule,  a  deposit  of  till  several  feet  in  depth  appears  along  the  drift 
border,  but  in  places  there  are  only  scattering  pebbles  for  a  mile  or  more 
back  from  it.  The  latter  feature  is  most  fi-equently  found  in  the  liilly  parts 
of  the  border. 

The  till  in  the  portion  of  southwestern  Indiana  south  of  East  White 
River  contains  a  remarkably  small  number  of  bowlders  and  coarse  frag- 
ments of  rock.  In  places  search  is  necessary  to  discover  a  pebble,  though 
in  a  neighboring  exjDosure  a  large  bowlder  may  be  found.  In  a  few  locali- 
ties sand  is  present  instead  of  clay,  but,  like  the  clay,  it  carries  very  few 
pebbles.  It  is  thought  that  these  peculiar  ^jhases  of  the  di'ift  may  be  due 
in  part  to  the  character  of  the  underlying  rocks  (there  being  a  prepon- 
derence  of  friable  strata  which  might  easily  be  reduced  to  clay  or  sand) 
and  in  part  to  imperfection  of  drainage  conditions,  by  which  the  very  fine 
material  was  all  retained  in  the  till  instead  of  being  allowed  to  escape 
down  the  valleys,  as  in  regions  to  the  west,  where  drainage  conditions  were 
better.  In  connection  with  the  fii'st  of  these  causes,  it  may  be  remarked 
that  the  local  rocks  throughout  the  entire  region  covered  by  this  glacial 
lobe  usually  form  so  large  a  proportion  of  the  coarse  constituents  of  till 
that  its  character  is  found  to  vary  in  a  pronounced  degi'ee  in '  accordance 
with  changes  in  the  underlying  rocks.  The  imperfection  of  di-aiuag-e  in 
southwestern  Indiana  attending  the  ice  invasion  was  such  that  several  lakes 
were  formed  in  valleys  wliich  lie  outside  the  di'ift  border  and  whose  streams 
had  discharged  westward  before  the  ice  invaded  the  territory  covered  by 
the  ice  sheet.  These  glacial  lakes  are  discussed  at  some  length  on  later 
pages,  as  are  also  the  changes  of  drainage  which  resulted  from  the  ice 
invasion.  North  from  East  White  River  the  till  usually  carries  a  moderate 
number  of  jiebbles,  and  differs  but  little  from  the  typical  till  of  the  interior 
portion  of  the  district  covered  by  tlie  Illinois  lobe.  The  coarse  rock  frag- 
ments are  composed  largely  of  sandstone  from  formations  which  outcrop 
in  the  immediate  vicinity  of  the  drift  border.     Canadian  rocks,  however, 


STRUCTURE  OF  THE  DRIFT  BORDER.  67 

are  well  represented,  and  bowlders  4  feet  in  diameter  are  occasionally 
found  on  the  immediate  drift  border. 

Eeference  will  be  made  to  a  few  of  the  wells  showing  thick  chift  and 
to  characteristic  exposures,  beginning  in  Posey  County  and  passing 
nortiieastward. 

The  thickest  drift  noted  in  Posey  Coimty  is  in  an  abandoned  valley 
which  connects  the  head  waters  of  Big  Creek  with  Black  River.  One  Avell 
iu  this  valley,  on  the  farm  of  Joseph  Nesbit,  about  a  mile  west  of  Cynthiana, 
penetrated  127  feet  of  drift,  and  entered  sandstone  at  that  depth.  The  well 
mouth  is  only  about  420  feet  above  tide  and  80  feet  above  the  neighboring 
portion  of  the  Wabash  River.  The  driller,  T.  F.  O'Herron,  of  Haubstadt, 
reports  that  the  entire  depth  is  a  stiff"  clay,  of  which  the  upper  Sf!  feet  has 
a  brown  or  yellow  color,  and  the  remainder  a  blue  color.  On  a  neighbor- 
ing farm,  owned  by  Joseph  Cale,  a  well  reached  a  depth  of  114  feet  without 
entering  rock.  In  this  Avell  two  thin  beds  of  fine  gravel  were  passed 
through.  Aside  from  these  the  drift  is  a  stiff  clay,  of  which  the  upper  40 
feet  is  yellowish  brown  and  the  remainder  a  blue  color. 

On  the  head  waters  of  Big  Creek,  in  northwestern  Vanderburg  County, 
several  wells  40  to  60  feet  in  dejoth  do  not  reach  rock.  This  valley  appears 
to  have  been  silted  up  to  a  depth  of  50  feet  or  more  in  the  portion  imme- 
diately outside  the  glacial  boundary.  Wells  there  are  reported  to  pass 
thi'ough  "  clay  and  quicksand"." 

In  the  %dcinity  of  Haubstadt,  within  a  mile  north  of  the  glacial  bound- 
ary, there  is  a  plain  in  winch  several  wells  have  penetrated  40  to  70  feet  of 
di'iffc  before  entering  rock.  The  upper  20  or  30  feet  is  yellowish-brown 
clay  and  the  remainder  blue  clay.  Occasionally  the  clay  maintains  a  yel- 
low color  to  a  dejDth  of  40  feet  or  more.  The  loess  in  that  region,  both 
outside  and  inside  the  glacial  boundary,  is  about  12  feet  in  thickness  and  is 
similar  in  color  to  the  oxidized  portion  of  the  underlying  glacial  di-ift. 

In  the  ridged  belt  near  Fort  Branch  there  are  several  hillside  exposures 
showing  a  few  feet  of  till  with  considerable  stony  material  just  below  the 
loess,  and  beneath  this  a  fine  sand.  The  wells  along  the  ridge  enter  a  soft 
blue  clay,  called  "blue  mud,"  at  a  dejjth  of  30  or  40  feet.  Only  one  well 
was  found  which  entered  rock.  This  is  located  at  the  residence  of  Lawrence 
Byers,  near  the  east  base  of  the  ridge,  and  reached  rock  at  a  depth  of  97 
feet.     Several  wells  along  the  crest  of  the  ridge,  50  to  100  feet  in  depth, 


(58  THE  ILLINOIS  GLACIAL  LOBE. 

do  not  enter  rock.  East  of  this  ridge,  along-  Sand}^  Fork  of  Pigeon  Cre6k, 
wells  are  usually  obtained  at  a  depth  of  25  feet  or  less.  In  some  instances 
they  penetrate  alternations  of  blue  clay  and  sand  beneath  the  loess,  while 
in  other  iiastances  nothing  but  sand  is  found.  In  some  of  the  ravines  lead- 
ing into  Sand}"  Fork,  a  gray  gummy  clay  carrying  a  few  small  pebbles 
immediately  underlies  the  loess.  It  appears  to  be  stained  with  humus,  and 
probably  represents  the  Sangamon  interglacial  stage.  A  creek  exposure  in 
the  southwest  part  of  sec.  23,  T.  2  S.,  R.  10  W.,  shows  a  red,  weather- 
stained,  sandy  gravel  below  the  loess. 

West  of  the  di'ift  ridge  along  Mudd}"  Fork  of  Pigeon  Creek,  wells 
usually  enter  blue  clay  at  about  30  feet,  and  in  several  instances  have  been 
sunk  to  a  depth  of  about  100  feet  without  reaching  rock.  One  well  3  miles 
west  of  Fort  Branch,  on  the  farm  of  Henry  Lehriug,  struck  rock  at  a  depth 
of  114  feet.  Two  miles  farther  west,  on  more  elevated  ground,  rock  is 
struck  at  12  to  20  feet. 

In  western  Pike  County,  Indiana,  in  sees.  13,  23,  24,  and  26,  T.  1  S., 
R.  9  W.,  several  roadside  exposures  of  till  having  a  thickness  of  5  to  10  feet 
were  found  apparently  at  the  extreme  limits  of  glaciation.  For  several  miles 
east  from  these  sections  the  thickness  of  the  drift  on  the  uplands  seldom 
exceeds  10  feet,  and  the  loess  here  is  reduced  to  a  thickness  of  but  5  or  6 
feet.  In  a  lowland  tract  along  Flat  Creek,  in  eastern  Pike  County,  which 
lies  near  the  glacial  Ijoundary,  the  drift  has  a  thickness  of  75  to  120  feet  or 
more.  At  the  village  of  Otwell,  which  stands  in  this  lowland,  Dr.  W.  M. 
De  Motte  made  a  boring  which  reached  a  depth  of  119  feet  without  strik- 
ing rock,  though  the  well  mouth  is  only  485  feet  above  tide,  and  scarcely  85 
feet  above  the  neighboring  portion  of  East  White  River.  A  boring  made  by 
William  Bell  near  the  head  waters  of  Mud  Creek  and  Flat  Creek,  6  miles 
west  of  Otwell,  reached  rock  at  a  depth  of  78  feet,  and  several  other  wells 
within  2  miles  north  and  east  are  reported  by  Mr.  Bell  to  have  reached  rock 
at  75  to  80  feet.  The  di'ift  in  this  lowland  is  reported  to  be  largely  a  blue  mud. 
There  is,  however,  considerable  sand  just  below  the  loess,  exposures  of  which 
may  be  seen  along  the  ravines  and  at  roadsides.  This  lowland,  as  indicated 
on  a  later  page,  was  apparently  the  line  of  discharge  for  a  part  of  the  Patoka 
drainage  basin  into  White  River,  wliich  it  entered  near  the  junction  of  the 
two  forks  east  of  Petersl)urg.  On  the  uplands  bordering  tliis  lowland  on 
the  north  and  east,  rock  is  usually  entered  at  35  feet  or  less,  while  on  the 


STEUCTURE  OF  THE  DEIFT  BOEDEE.  69 

uplands  to  the  south  it  is  found  at  6  to  10  feet,  there  being  httle,  if  any, 
drift  present. 

As  ah'eady  noted,  in  northwestern  Dubois  County  there  is  a  low  plain 
covering  about  50  square  miles  in  wliich  the  loess  is  underlain  by  sand. 
The  sand  appears  to  have  been  deposited  in  the  glacial  lake  Patoka,  formed 
by  the  obstruction  of  the  Patoka  River  by  the  ice  sheet,  the  preglacial 
course  of  the  river  having  been  northwestward  across  this  plain  into  East 
White  River.  The  plain  was  built  up  to  a  level  of  about  480  feet  above 
tide,  which  has  been  increased  to  485  to  490  feet  by  the  subsequent  loess 
deposit.  The  surface  of  the  sand  at  the  base  of  the  loess  is  deeply  weather- 
stained,  showing  that  it  long  antedated  the  loess  in  deposition.  On  the 
borders  of  this  plain,  about  3  miles  north  of  Jasper,  in  sec.  15,  T.  1  S., 
R.  5  W.,  an  exposure  of  black  soil  was  found  immediately  below  the  loess, 
which  was  apparently  formed  in  the  Sangamon  interglacial  stage.  The 
.clay  below  it  contains  a  few  glacial  pebbles. 

In  southeastern  Daviess  County,  as  noted  above,  the  drift  for  a  mile  or 
two  back  from  the  glacial  boundary  is  reduced  to  a  few  scattering  pebbles. 
A  heavy  sheet  of  till  there  sets  in,  which  fills  the  country  to  a  nearly 
uniform  level  and  produces  plains  known  as  "the  flats,"  on  which  the  drift 
ranges  from  20  to  80  feet  or  more  in  depth.  The  plane  surface  extends 
nearly  to  the  glacial  boundary  in  the  vicinity  of  Whitfield,  Mount  Pleasant, 
and  Loogootee,  in  Martin  County.  There  are,  however,  scattering  pebbles 
on  the  hills  along  the  east  border  of  the  plain.  On  a  tributary  of  Boggs 
Creek,  2  miles  north  of  Loogootee,  exposures  of  till  occur  30  feet  or  more 
in  height,  in  one  of  which  a  granite  bowlder  4  feet  in  diameter  was  noted. 
Along  much  of  the  boundary  from  Loogootee  to  Scotland  the  drift  is  very 
thin,  though  it  apparently  forms  a  nearly  continuous  sheet.  There  are  low 
hills  along  the  east  border  of  Daviess  County  which  for  several  miles  inside 
the  glacial  boundary  show  only  a  thin  coating  of  drift.  But  the  lowlands 
in  that  region  have  apparently  been  filled  to  considerable  depth. 

At  Scotland  and  along  ravines  northeastward  there  are  exposures  of 
sandy  till  10  to  20  feet  in  depth  at  points  within  a  mile  of  the  apparent  limits 
of  glaciation.     The  hills  in  that  region,  however,  carry  very  little  drift. 

In  the  lowland  tract  north  of  Plummer's  Creek  there  are  heavy  depos- 
its of  sand,  which  in  places  are  cajDped  by  a  few, feet  of  fine  gravel,  apparently 
a  glacial  deposit.     The  filling  amounts  to  75  or  100  feet,  and  seems  excess- 


70  THE  ILLINOIS  GLACIAL  LOBE. 

ive  when  compared  with  the  amount  of  drift  on  neighljoring  hills.  On 
some  of  the  hills  between  Rockwood  and  Park  post-office,  there  is  scarcely 
a  trace  of  drift,  though  they  are  surrounded  by  the  lowlands  in  which 
heavy  deposits  of  drift  occur.  The  drift  continues  thin  on  uplands  as  far 
north  as  Richland  Creek,  and  the  boundary  is  located  with  some  difficulty. 

From  the  naiTows  of  Richland  Creek,  in  sees.  8  and  9,  T.  7  N.,  R.  4  W., 
northeastward  to  Newark,  there  is  an  exceptionally  large  amount  of  drift  in 
the  vicinity  of  the  glacial  boundary,  both  on  uplands  and  on  lowlands. 
Several  exposures  were  found  200  feet  above  the  creek,  in  Avhich  there  is 
not  less  than  50  feet  of  drift.  The  old  course  of  Richland  Creek,  through 
a  lowland  tract  east  of  Newark,  has  been  filled  up  to  a  height  of  nearly  100 
feet  above  the  creek  with  deposits  of  sandy  clay,  carrying  a  liberal  admix- 
tm-e  of  coarse  rock  material  and  an  occasional  bowlder. 

Siebenthal  reports  that  in  southeastern  Owen  County  the  drift  is  heavy 
in  the  valleys,  but  comparatively  thin  on  the  hills,  and  this  feature  is  char- 
acteristic of  the  boundar}^  in  Monroe  County  and  southern  ^Morgan  Countv, 
as  noted  both  by  Siebenthal  and  by  the  writer.  Small  bowlders  are  present 
in  moderate  number  in  the  ^sdcinity  of  the  gdacial  boundary  in  all  these 
counties. 

CHARACTER  OF  THE  OUTWASH. 

There  appears  to  have  been  very  little  material  carried  out  by  water 
beyond  the  edge  of  this  ice  sheet  except  along  the  valleys.  While  the 
outer  border  plains  and  the  small  valleys  heading  in  this  di-ift  margin  occa- 
sionally bear  thin  deposits  of  sand  and  fine  gravel  which  seem  to  be  an 
outwash  from  the  ice  margin,  there  is  nothing  comparable  to  what  is  dis- 
played along  some  moraines  of  the  Wisconsin  stage  described  below. 

The  best  exposure  of  such  an  outwash  yet  noted  is  found  near  West 
Point,  in  Lee  County,  Iowa.  About  a  mile  northwest  of  the  -sallage,  imme- 
diately outside  the  lUinoian  drift  border,  the  following  series  of  deposits  is 
exposed  in  the  gradings  along  an  east-west  road : 

Section  near  West  Point,  Iowa,  shou-ing  (/ravel  oiiticu.^h. 

Feet. 

1.  Brown  silt,  apparently  to  be  classed  with  the  lowan  loess 7 

2.  Fine  gravel,  ronsiilereil  an  outwash  from  the  lUinoiau  <hift 1  to   2 

3.  Ash-colored  soil,  representing  the  Yarmouth  interglacial  stage 1+  to    2 

4.  Kansan  till,  brown  ;it  top,  becoming  a  yellowish  gray  at  bottom,  exposed 15  to  20 

The  full  extent  of  the  gravelly  outwash  at  this  place  is  not  known, 
because  of  the  silt  co^'er,  l)ut  it  seems  to  he  resti-icted  to  a  strip  extending 


EIDGED  DRIFT  OF  KASKASKIA  BASIK.  71 

scarcely  one-half  mile  out  from  the  margin  of  the  lUinoian  drift.  The 
presence  of  the  soil  beneath  this  gravel  makes  it  evident  that  there  was  but 
little  erosion  accompanying  the  deposition  of  the  gravel.  It  also  shows  that 
the  gravel  is  not  a  residue  of  coarse  material  formed  in  the  process  of  ero- 
sion of  the  Kansan  till  sheet,  either  before  or  after  the  lUinoian  glaciation. 

The  principal  valley  affording  a  line  of  drainage  for  the  ice  sheet  was 
the  Mississippi,  only  short  sections  of  the  eastern  tributaries  being  outside 
the  Illinoian  drift  margin.  This  valley  was  covered  by  the  ice  sheet,  as 
already  indicated,  from  near  the  south  end  of  the  Driftless  Area  down  to 
the  vicinity  of  Fort  Madison,  Iowa.  Possibly  also  it  was  encroached  upon 
for  a  few  miles  in  the  vicinity  of  St.  Louis,  Missouri.  The  blockade  in  the 
portion  bordering  eastern  Iowa  was  so  complete  as  to  cause  the  opening  of 
a  temporary  line  of  drainage  across  eastern  Iowa  outside  the  ice  margin,  as 
indicated  below;  but  there  appears  to  have  been  at  most  only  a  partial 
blockade  near  St.  Louis.  An  examination  into  the  character  of  the  deposits 
in  the  Mississippi  Valley,  between  Fort  Madison  and  St.  Louis,  has  brought 
to  light  nothing  to  indicate  vigorous  di-ainage  at  the  Illinoian  stage  of  glaci- 
ation. Indeed,  the  valley  seems  to  have  become  filled  to  some  extent  by 
sand  and  finer  material  at  places  where,  previous  to  this  glaciation,  erosion 
had  been  in  progress.  This  is  markedly  the  case  just  below  the  lower 
rapids.  The  filling  there  is  mainly  silt  and  fine  sand,  though  a  fine  gravel 
appears  in  places  where  the  cm-rent  was  strongest.  This  matter  is  discussed 
more  fully  below  (pp.  94-96).  In  the  section  of  the  Mississippi  also  between 
St.  Louis  and  Cairo  only  sand  and  silt  are  found  along  the  valley,  a  feature 
that  apparently  indicates  a  drainage  no  more  vigorous  than  at  the  present 
day.  Yet  it  seems  probable  that  at  times  the  volume  of  water  greatly 
exceeded  that  now  dischai'ged  thi-ough  the  valley. 

Much  remains  to  be  learned  concerning  the  drainage  conditions  attend- 
ing this  and  later  stages  of  glaciation,  but  from  what  is  now  known  the 
drainage  at  the  Illinoian  stage  appears  to  have  been  very  sluggish  not 
only  on  the  Mississippi,  but  on  all  the  valleys  leading  away  from  the  ice 
sheet. 

THE   RIDGED    DRIFT    OF    THE    KASKASKIA    BASIIJ^. 

The  position  of  the  principal  ridges  in  this  system  may  be  seen  by 
reference  to  the  glacial  map  (PI.  VI).  It  will  be  observed  that  there  is  one 
belt  lying  near  the  Kaskaskia  River  and  found  chiefly  on  its  west  border. 


72  THE  ILLIis^OIS  GLACIAL  LOBE. 

Another  belt  a  few  miles  to  the  west  runs  nearly  parallel  to  the  river  from 
Tower  Hill,  in  Shelby  County,  southwestward  to  Belle^'ille,  in  St.  Clair 
County.  Still  farther  west  there  is  a  system,  less  definitely  developed, 
leading  from  northern  Montgomery  County  southward  into  northeastern 
Madison  County.  South  from  Belleville  the  ridges  are  reduced  to  a  single 
chain  which  follows  the  west  border  of  the  Kaskaskia  fi-om  Lementon,  in 
St.  Clair  Coimty,  southward  across  eastern  Monroe  into  northern  Randolph 
Coimty.  The  ridge  there  crosses  to  the  east  side  of  the  river  and  passes 
southeastward  near  Sparta  to  Steelville.  There  is  a  slight  ridging  as  far 
southeast  as  central  Jackson  County,  beyond  which  the  drift  appears  not  to 
be  definitely  ridged.  There  are,  however,  occasional  low  i-idges  and  swells 
in  the  ^dcinity  of  the  glacial  boundary  in  WilHamson,  Saline,  and  Grallatin 
counties,  which  may  mark  the  continuation  of  the  belt. 

Of  the  three  systems  developed  northeast  of  Belleville  the  middle  one 
is  the  best  defined  and  most  nearly  continuous.  It  is  inteiTupted  only  by 
a  few  naiTow  gaps,  usually  less  than  2  miles  in  width,  throughout  the  entire 
distance  from  Tower  Hill  to  Belleville,  nearly  100  miles.  There  are  places, 
as  in  northeastern  Montgomery  and  in  southeastern  Madison  County,  where 
a  continuous  ridge  is  maintained  for  a  distance  of  at  least  15  miles.  The 
belt  bordering  the  Kaskaskia  River  is  maintained  for  several  miles  as  a 
continuous  ridge  in  the  vicinity  of  Vandalia,  but  elsewhere  is  represented 
only  by  fragmentary  ridges,  seldom  more  than  3  miles  in  length,  between 
which  there  may  be  gaps  of  even  greater  length.  The  western  of  the  three 
belts  is  even  more  fragmentary,  and  is  maintained  for  only  20  ov  25  miles. 

These  ridges  are  usually  rather  sharp  and  narrow,  but  in  places  assume 
a  billowy  topogi'aphy.  In  still  other  places  they  have  a  vague  irregularity 
of  form  and  an-angement.  The  more  sharply  ridged  type,  however,  pre- 
vails over  the  others,  and  may  be  said  to  characterize  the  system.  The 
sharpest  ridge  noted  is  that  in  the  ^dcinity  of  Cool  Spring  post-office,  in 
Shelby  County,  where  a  ridge  scarcely  a  mile  in  width  has  a  height  of  130 
feet.  A  long  ridge  leading  from  Pocahontas,  in  Bond  Coimty,  westwai-d 
into  Madison  County,  and  thence  southward  to  the  village  of  Highland,  is 
about  50  feet  in  average  height  and  scarcely  a  half  mile  in  average  width. 
Knolls  75  or  100  feet  in  height  are  not  rare,  and  occur  in  nearly  every 
county  traversed  by  this  system  of  ridges.     These  knolls,  as  well  as  the 


EIDGED  DRIFT  OP  KASKASKIA  BASra.  73 

ridges,  often  rise  abruptly  from  very  flat  tracts,  and  seldom  shade  into  the 
bordering  plain,  a  feature  which  distinguishes  them  from  the  moraines  of 
the  Wisconsin  series,  which  usually  grade  into  plane  tracts  on  their  inner 
border. 

The  ridge  leading  southeastward  from  the  Kaskaskia  across  north- 
eastern Randolph  and  western  Jackson  counties  is  not  so  sharp  as  the 
majority  of  ridges  west  of  the  Kaskaskia,  and  has  a  gently  undulating  sur- 
face, similar  to  that  of  the  ridges  formed  on  the  drift  border  in  western 
Illinois  and  southeastern  Iowa.  It  seems,  however,  to  be  definitely  con- 
nected with  the  system  of  ridges  following  the  west  side  of  the  Kaskaskia, 
and  can  scarcely  be  included  with  the  ridges  which  characterize  the  drift 
border. 

The  entire  system  of  ridges  is  composed  largely  of  typical  till,  blue 
till  being  present  in  the  lower  portions  and  brown  till  near  the  surface.  In 
a  few  cases  gravel  and  sand  have  been  found,  but  such  material  is  so  rare 
that  railways  have  not  found  it  expedient  to  obtain  ballast  from  these  ridges. 

The  origin  or  mode  of  formation  of  these  ridges  is  problematical. 
Their  trend  is  nearly  in  line  with  the  ice  movement,  as  shown  by  striee 
in  the  neighborhood  of  Alton,  in  Madison  County,  and  is  about  at  right 
angles  witli  the  course  of  the  boundary  of  the  Illinoian  drift  sheet.  Several 
working  hypotheses  were  employed  during  the  field  investigations,  among 
which  may  be  mentioned  the  following:  (1)  That  the  ridges  are  similar  in 
origin  to  drumlins.  (2)  That  the  ridges  constitute  an  interlobate  morainic 
system  formed  in  a  reentrant  between  a  supposable  lobe  which  covered 
western  Illinois  and  one  which  covered  southern  Illinois  and  southwestern 
Indiana.  (3)  That  the  ridges  mark  the  western  border  of  a  lobe  which 
persisted  in  southern  Illinois  after  the  ice  had  retreated  from  western  Illinois. 
(4)  That  the  ridges  are  dependent  in  some  way  upon  obstructing  rock  hills 
which  constitute  their  nuclei.  (5)  That  the  rfdges  are  a  remnant  of  a  sheet 
of  drift  which  once  filled  that  region  to  the  height  of  their  crests. 

In  the  study  of  these  ridges  it  was  found  that  in  a  few  instances  they 
bear  resemblance  to  drumlins  in  their  form,  but  the  great  majority  bear 
little  or  no  likeness  to  that  class  of  ridges.  The  hypothesis  of  an  origin 
similar  to  drumlins  is  therefore  held  somewhat  lightly,  but  is  not  rejected. 

The  hypothesis  that  these  ridges  were  formed  as  an  interlobate  belt 


74  THE  ILLINOIS  GLACIAL  LOBE. 

lacks  support  because  of  the  absence  of  a  system  of  ridges  leading  up  from 
the  west.  It  is  perhaps  opposed  by  the  direction  of  the  neighboring  strife 
at  Alton,  which  is  sonthwestward,  parallel  with  the  ridges,  instead  of  south- 
eastward toward  them.  This  hypothesis,  therefore,  is  held  lightly,  but  is 
not  rejected. 

The  hypothesis  that  this  system  of  ridges  marks  the  western  border  of 
a  lobe  which  persisted  in  southern  Illinois  after  the  withdi-awal  of  the  ice 
from  western  Illinois  is  apparently  supported  by  the  distribution  of  the 
ridges.  This  is  especially  true  of  the  southeastward  extension  of  the  belt 
across  Randolph  and  Jackson  counties  which,  in  a  measure,  encircles  the 
supposed  lobe.  This  hypothesis  apparently  is  the  best-supported  one  of 
the  group. 

The  hypothesis  that  rock  hills  ma.j  constitute  nuclei  for  the  ridges  was 
suggested  by  the  occurrence  of  such  hills  in  western  Shelby  County,  in  the 
midst  of  the  system  of  ridges,  but  no  evidence  was  found  elsewhere  along 
the  belt  which  would  support  this  ^dew.  Indeed,  the  majority  of  ridges 
have  such  abruptness  that  they  can  scarcely  be  supposed  to  can-y  an  equally 
abrupt  ridge  of  rock.  The  formations  in  that  region  are  largely  shale  or 
shaly  sandstone  which,  in  all  probability,  would  be  preserved  only  in  low 
hills  and  ridges  with  gentle  slope. 

The  hypothesis  that  the  ridges  are  remnants  of  a  sheet  of  drift  which 
once  covered  this  region  to  the  height  of  their  crests  is  presented  in  the 
Illinois  Geological  Reports  as  an  explanation  for  their  occmTence.  This 
hypothesis  involves  such  a  vast  amount  of-  erosion  as  to  be  entirely  unsup- 
ported by  the  features  of  the  region,  and  is  therefore  no  longer  considered 
applicable. 

BUFFALO  HART  MORAISTE. 

The  Buifalo  Hart  moraine  is  well  defined  for  a  distance  of  about  15 
miles  in  eastern  Sangamon  and  southwestern  Logan  counties,  passing  from 
the  Sangamon  River  near  ]\Iount  Auburn  northwestward  past  Buffalo  and 
Buffalo  Hart  to  Elkhart.  It  consists  of  knolls  of  considerable  prominence, 
somewhat  closely  aggregated,  many  of  which  are  30  or  40  feet  and  a  few 

75  or  80  feet  or  more  in  height.  Among  the  knolls  there  are  sloughs  and 
shallow  basins,  giving  the  surface  a  subdued  type  of  knob-and-basin  topog- 


BUFFALO  HART  MOEAINE.  75 

raphy.  This  belt  has  an  average  width  of  nearly  2  miles.  East  from  it 
there  are  scattering  knolls  of  considerable  prominence,  one  at  the  town  of 
Mount  Pulaski  being  nearly  30  feet  in  height. 

The  connections  of  this  belt  with  other  moraines  are  rather  vas-ue. 
There  is,  however,  toward  the  southeast,  a  series  of  mounds  and  short  ridges 
occupying  the  interval  between  the  southern  end  of  this  moraine  and  the 
northern  end  of  the  ridged  drift  of  the  Kaskaskia  Basin.  In  case  those 
ridges  prove  to  have  been  formed  by  an  ice  sheet  occupying  the  district  east 
of  them,  the  Buffalo  Hart  moraine  would  seem  to  be  a  natural  northward 
continuation  of  the  belt. 

The  northern  terminus  of  the  Buffalo  Hart  moraine  is  in  the  form  of  a 
very  prominent  mound,  rising  150  feet  above  the  bordering  country,  or 
about  twice  as  high  as  any  of  the  other  knolls  in  the  moraine.  It  is  known 
as  Elkhart  Mound,  being  situated  about  a  mile  east  of  the  village  of  Elkhart, 
and  has  been  a  landmark  from  the  early  days  of  settlement.  It  commands 
a  view  for  20  miles  or  more  in  all  directions.  From  this  mound  a  low  ridge 
leads  off  westward  about  3  miles,  where  it  merges  into  the  general  upland 
plain.  There  are  two  lines  of  possible  continuation  for  this  moraine.  The 
eastern  line  would  lead  northward  throtigh  western  Logan  and  eastern 
Mason  counties  and  embrace  a  series  of  knolls  scattered  over  that  reo'ion. 
The  western  line  would  follow  the  low  ridge  westward  and  cross  the  Illinois 
River  near  the  month  of  Sangamon  River  and  there  connect  with  the  small 
drift  ridge  mentioned  above  which  occupies  southern  and  western  Fulton 
County.  The  features  are  too  vague  to  make  a  satisfactory  correlation 
along  either  line.  It  seems  preferable,  therefore,  to  leave  the  belt  without 
an  attempt  at  definite  coiTelations. 

The  drift  in  this  moraine,  like  that  in  the  bordering  plain,  consists 
mainly  of  till.  Even  the  veiy  prominent  Elkhart  Mound  has  till  exposed 
where  the  road  crosses  its  northern  slope.  There  are,  however,  local  devel- 
opments of  gravelly  material  in  some  of  the  knolls  and  ridges,  as  in  the 
Kaskaskia  system  of  ridges.  The  moraine  is  covered  with  loess,  usually  to 
a  depth  of  12  or  15  feet,  and  this  obscm-es  greatlj^  the  underlying  drift  and 
renders  it  difficult  to  discover  places  where  gravel  may  be  obtained. 

The  knolls  scattered  over  southern  and  western  Logan  County  have 
been  found  in  some  cases  to  contain  considerable  sand,  but  they  also,  Hke 
the  knolls  of  the  moraine,  appear  to  be  composed  principally  of  till. 


76  THE  ILLINOIS  GLACIAL  LOBE. 

The  low  drift  ridge  of  southern  and  western  Fulton  County  consists  of 
till  in  its  smoothest  portions,  but  there  are  a  few  knolls  in  the  northwest 
part  of  Fulton  County  which  are  of  gravelly  constitution.  In  this  con- 
nection it  may  be  remarked  that  the  sections  of  wells  made  on  Imolls  in 
western  Illinois  so  far  as  obtained  exhibit  as  a  rule  much  more  till  than 
sand  or  gravel.  In  short,  it  may  be  said  that  the  ridged  drift  and  knolls  of 
the  Illinoian  sheet  are  generally  composed  mainly  of  till  and  differ  but 
little  from  the  drift  of  the  plane  tracts  which  border  them.  But  in  north- 
western Ilhnois  the  ridges  of  the  sheet  tentatively,  referred  to  the  Illinoian 
are  largely  of  gravelly  structure  and  some  are  of  esker  tyjDe. 

ESKERS  OR  GRAVELLY  RIDGES  OF  NORTHWESTERN  ILLINOIS 

Leaf  River  or  Adeline  esker. — The  largcst  aud  bost-defined  esker  found  in  north- 
western Illinois  stands  in  the  valley  of  Leaf  River  in  northern  Ogle  County, 
and  is  discussed  by  Hon.  James  Shaw  in  the  report  on  Ogle  County.^ 

It  has  been  discussed  more  recently  by  Mr.  Oscar  Hershey,  who  has 
applied  to  it  the  name  Adeline,  from  the  village  of  Adeline,  situated  near  its 
eastern  end.^ 

As  Judge  Shaw's  report  was  prepared  before  the  distinguishing  char- 
acteristics of  eskers  were  fully  known,  the  name  moraine  was  very  natui-ally 
applied  to  the  ridge.  This  reference  of  the  ridge  to-  glacial  action  is  of 
interest,  since  Shaw  had,  prior  to  the  examination  of  it,  followed  the  State 
geologist.  Professor  Worthen,  in  the  support  of  the  iceberg  hypothesis  as  an 
adequate  explanation  for  the  drift  phenomena  of  northwestern  Illinois. 
Chamberlin  was  apparently  the  first  to  recognize  this  ridge  as  an  esker,  on 
a  visit  made  to  it  about  1881,  in  his  studies  preparatory  to  the  writing  of 
the  paper  in  the  Third  Annual  Report.^  The  writer's  examinations  were 
made  in  the  spring  of  1886.    . 

The  esker,  as  may  be  seen  by  reference  to  PI.  XII,  is  a  jjra'ctically  con- 
tinuous ridge  about  12  miles  in  length,  extending  from  a  point  1  mile  east 
of  Adeline  westward  to  sec.  14,  T.  25,  R.  7  E.,  about  5  miles  northwest 
from  Forreston.     The  only  notable  gap  occurs  where  a  branch  of  Leaf  River 


'  Geol.  of  niinois,  Vol.  V,  1873,  pp.  108-109. 
^Am.  Geol.,  Vol.  XIX,  1897,  pp.  200,201. 

'Preliminary  paper  on  the  terminal  moraine  of  tlio  second  Glacial  epoch,  by  T.  C.  ChamV)erlin: 
Third  Ann.  Kept.  U.  S.  (ieol.  Survey,  1883,  pp.  L''Jl-402. 


ESKEES  OF  NOETHWESTEEN  ILLIXOIS.  77 

breaKs  through  the  ridge,  2  miles  west  of  Adeline.  The  crest  line  is  very 
uneven  and  the  height  of  the  ridge  varies  gi-eatly.  The  highest  points 
slightly  exceed  100  feet  above  the  plain  bordering  Leaf  River,  but  their 
elevation  is  no  greater  than  that  of  the  uplands  on  either  side  of  Leaf  River 
Valley.  The  lowest  points  are  scarcely  20  feet  in  height.  The  esker  con- 
sists usually  of  but  a  single  ridge,  ranging  in  breadth  from  100  feet  or  less 
to  probably  1,000  feet.  At  its  eastern  end,  in  the  vicinity  of  Adeline,  there 
is  a  series  of  nearly  parallel  ridges  and  hillocks  covering  a  breadth  of  per- 
haps one-half  mile  and  almost  filling  the  valley.  At  the  western  end  of 
the  ridge  there  is  no  delta,  or  fan-shaped  gravel  deposit,  such  as  sometimes 
occurs  at  the  terminus  of  an  esker.  There  are  a  few  small  gravel  knolls 
within  a  mile  north  from  its  terminus,  but  the}'  do  not  appear  to  be  definitely 
connected  with  it. 

Several  extensive  excavations  have  been  made  in  the  esker,  some 
of  which  expose  its  sti-ucture  from  top  to  bottom.  It  is  made  up  largely 
of  coarse  gravel  well  rounded,  but  contains  also  beds  of  fine  gravel  and 
sand.  The  coarser  material  is  most  abundant  in  the  upper  portion  and 
it  is  not  rare  to  find  bowlderets,  and  even  moderate-sized  bowlders, 
embedded  in  it.  The  lower  portion  displays  much  cross  bedding.  The 
direction  of  flow  of  the  stream  which  formed  this  esker  is  clearly  shown  to 
be  toward  the  west,  or  the  reverse  of  the  present  drainage  of  the  Leaf  River 
Valley.  As  the  esker  now  stands,  its  western  end  is  nearly  100  feet  higher 
than  its  eastern.  In  case  the  esker  was  formed  under  the  ice  in  the  valley 
which  it  occupies,  considerable  hydi-ostatic  pressure  would  have  been 
required  to  force  the  water,  with  its  burden  of  gravel,  up  this  slope.  It 
does  not,  however,  seem  necessary  to  restrict  the  formation  of  the  esker  to 
the  under  surface  of  the  ice  sheet,  since  it  is  found  that  nearly  stagnant  ice 
is  traversed  by  tunnels  at  some  distance  above  its  base.^  The  greater  part 
of  the  gravel  is  composed  of  limestone  such  as  occurs  in  the  neighboring 
ledges,  but  there  is  also  a  liberal  admixture  of  rocks  of  distant  derivation. 
In  order  to  compare  the  rock  constituents  of  the  esker  with  those  of  the  till 
of  the  adjacent  districts,  pebbles  were  taken,  without  attempt  at  selection, 
from  the  esker  and  from  a  dump  at  the  mouth  of  a  well  at  Forreston,  which 

'  See  I.  C.  EuaseU,  Jour.  Geol.,  April-May,  1893,  Vol.  I,  No.  3,  pp.  240-242.  See  also  Hershey's 
discussion  in  Am.  Geologist,  April,  1897,  pp.  238-239. 


78 


THE  ILLINOIS  GLACIAL  LOBE. 


had  just  been  excavated  in  till.     Upon  classifying  the  rocks  the  following 
results  were  obtamed: 

Pebbles  classified  from  an  eslcer  and  the  till  near  Forreston,  Illinois. 


Esker. 


TiU. 


Granite 

Dark-colored  basic  eruptives 

Red  quartz-porphyry • 

Quartzite 

Quartz 

Siliceous  shale  and  thin-bedded  sandstone 

Brown  chert 

White  chert 

Yellow  limestone,  largely  Galena 

Blue  and  gray  limestone  (Lockport  and  Trenton) 

Total 


6 

6 

1 

1 

1 

0 

8 

21 

86 

56 


0 
0 
2 

6 
3 

21 
76 
59 


180 


176 


Several  fossils  were  found  in  jjebbles  of  Lockport  limestone,  and  also 
characteristic  fossils  of  the  Trenton  and  Galena,  both  by  the  writer  and  by 
other  persons  who  have  discussed  this  ridge.  As  the  latter  formations  have 
an  outcrop  for  only  40  or  60  miles  to  the  east,  the  material  may  confidently 
be  considered  of  local  or  semilocal  derivation. 

Hazeihurst  esker. — A  shoit  cskcr  is  fouud  ucar  Hazelhurst,  at  the  borders  of 
Ogle  and  Carroll  counties.  (See  PI.  XII.)  The  esker  proper  is  a  sharp 
ridge  about  li  miles  in  length,  rising  just  west  of  Hazelhurst  to  a  height  of 
fully  100  feet  above  the  station  and  maintaining  a  height  of  60  to  75  feet 
for  a  distance  of  nearly  a  mile.  Its  eastern  end  is  about  a  half  a  mile  east 
of  the  village,  and  the  western  end  about  a  mile  northwest.  The  ridge  is 
practically  continuous,  but  has  a  slight  deflection  in  its  middle  portion,  one 
ridge  terminating  and  another  beginning  a  short  distance  south  and  immedi- 
ately opposite  the  end  of  the  former.  The  general  trend  of  the  esker  is 
east  to  west,  but  the  western  end  points  northwest.  There  is  no  delta-shaped 
deposit  of  gi-avel  at  the  Avestern  end.  On  the  conti-ary,  the  ridge  contains 
considerable  till  at  that  terminus.  Several  gravel  pits  have  been  made  in 
the  ridge  near  its  eastern  end,  wliicli  show  it  to  be  composed,  like  that  of 
the  esker  in  Leaf  River  Valley,  of  very  coarse  material  at  the  top  and  liner 
material  in  the  basal  portion.  The  pebbles  are  mainly  limestone  of  local 
or  semilocal  derivation,  as  in  the  esker  just  discussed. 


ESKERS  OF  NORTHWESTERN  ILLINOIS.  79 

This  esker  is  situated  at  the  eastern  edge  of  a  basin  formed  in  the 
Hudson  River  shales,  which  is  drained  by  Elkhorn  Creek  and  is  known  as  the 
Elkhorn  Basin.  The  neighboring  districts  on  the  northeast  reach  an  eleva- 
tion nearly  as  high  as  the  crest  of  the  esker.  A  well  made  on  the  slope  of 
the  esker  a  short  distance  west  of  Hazelhurst  shows  that  the  di-ift  at  that 
jjoint  extends  nearly  100  feet  below  the  base  of  the  ridge  and  is  composed 
entirely  of  sand  and  gravel,  but  at  the  village  of  Hazelhurst  rock  is  reported 
to  be  struck  in  wells  at  a  depth  of  only  20  feet. 

There  are  several  prominent  gravel  knolls  in  the  immediate  vicinity  of 
the  Hazelhurst  esker,  two  of  which  reach  a  height  of  about  100  feet,  the 
others  being  20  to  40  feet  high.  They  are  situated  immediately  south  of 
the  esker,  and  are  scattered  over  a  width  of  a  mile  or  more  and  a  length 
from  east  to  west  of  more  than  2  miles.  These  knolls  are  slightly  elongated 
in  an  east-west  direction  in  several  cases,  but  the  two  prominent  ones  are 
nearly  conical.  It  seems  jDrobable  that  they  were  formed  by  agencies  simi- 
lar to  those  which  produced  the  esker — i.  e.,  by  glacial  drainage — and  they 
are  referred  to  the  same  esker  system. 

Garden  Plain  esker. — In  wcstcrn  Wlilteslde  County  there  is  a  small  esker  set- 
ting in  immediately  west  of  the  village  of  Garden  Plain,  and  passing  thence 
westward  through  the  north  part  of  sees.  22  and  21,  and  terminating  on  the 
Mississippi  bluif  in  sec.  20,  Garden  Plain  township.  It  lies  along  the  south 
side  of  the  wagon  road  which  leads  west  from  Garden  Plain,  and  in  its 
entire  length  of  2  J  miles  does  not  vary  20  rods  from  a  direct  east-west  line. 
The  ridge  has  usually  a  height  of  but  5  or  10  feet  and  a  breadth  of  20  rods 
or  less.  Its  structure  is  exposed  only  at  one  place,  at  a  gravel  pit  in  the 
west  part  of  sec.  22.  The  beds  here  bear  clear  evidence  of  a  westward- 
flowing  sti-eam.  The  gravel  has  remarkably  fresh  appearance,  being  stained 
but  little  more  than  the  usual  stain  of  the  Wisconsin  eskers,  and  much  less 
than  the  stain  presented  by  the  gravels  in  the  Hazelhurst  and  Leaf  River 
eskers.  It  is  barely  possible  that  it  was  formed  at  the  lowan  stage  of  gla- 
ciation,  though,  as  shown  below,  evidence  of  the  presence  of  the  lowan  ice 
sheet  in  this  region  is  far  from  decisive.  The  direction  of  flow  of  the  stream 
which  formed  the  esker  being  westward,  the  ridge  can  scarcely  be  referred 
to  a  movement  of  the  waters  from  the  lobe  of  lowan  ice  which  covered  the 
district  to  the  west  of  the  Mississippi,  even  if  that  ice  lobe  crossed  into  Illi- 
nois.    It  would  seem,  therefore,  that  the  esker  must  be  refen-ed  either  to  the 


80  THE  ILLINOIS  GLACIAL  LOBE. 

Illinoiau  iuvasiou  or  to  au  extension  of  the  lowau  ice  westward  from  the 
Rock  River  Basin. 

pecatonica  eskcr  system. — In  Stephensoii  Countj  there  are  several  gravelly 
belts  wliich  have  been  studied  in  considerable  detail  by  Mr.  Oscar  Hershey 
and  are  discussed  by  him  in  a  recent  paper  in  the  American  Geologist.' 
These  gravelly  belts  bear  less  resemblance  to  typical  eskers  than  the  Adeline 
and  Hazelhurst  ridges.  They  are  marked  by  frequent  interruptions  and 
display  a  series  of  branches  or  spurs  which  give  them  greater  complexity 
than  the  ridges  just  discussed.  The  main  belt  follows  the  Pecatonica  Valley 
from  eastern  Stephenson  County  w-estward  to  the  mouth  of  Yellow  Creek, 
about  3  miles  east  of  Freeport;  thence  it  passes  up  the  south  side  of  Yellow 
Creek  to  the  village  of  Bolton.  The  length  of  this  belt  is  nearly  20  miles, 
and  the  ridges  are  in  places  scattered  over  a  width  of  2  or  3  miles.  Their 
distribution  may  be  seen  on  PL  XII.  It  will  be  noted  that  there  are  usually 
two,  and  in  places  several,  parallel  ridges  traceable  for  a  few  miles;  they 
then  either  diverge  to  form  branch  belts  or  die  out  altogether.  Hershey  has 
called  attention  to  points  of  special  development  in  these  belts  where  the 
aggregate  bulk  of  the  ridges  is  increased  to  several  times  the  usual  amount. 
One  of  these  points  of  special  development  occurs  opposite  the  mouth  of 
Yellow  Creek,  another  3  or  4  miles  farther  west,  and  a  third  at  the  westeiTi 
end  of  the  belt  at  Bolton.  These  are  interpreted  by  Hershey  to  have  been 
formed  successively  from  Avest  to  east,  and  to  mark  each  tlie  position  of  the 
ice  margin  at  the  time  it  was  forming.  The  ingenious  hypothesis  which 
Hershey  has  presented  may  perhaps  satisfactorily  account  for  the  develop- 
ment of  these  belts,  but  the  question  can  scarcely  be  decided  in  the  present 
state  of  knowledge  of  such  phenomena. 

At  the  western  end  of  this  gravelly  belt  the  ridges  culminate  in  an 
accumulation  of  greater  strength  than  is  displayed  at  any  other  point  along 
the  belt.  An  area  of  more  than  a  square  mile  is  occupied  by  sharp  ridges, 
the  highest  of  which  rise  75  or  100  feet  above  the  adjoining  plain.  The 
plain  immediately  west  of  this  system  of  ridges,  though  imperfectl)-  exposed 
to  view,  is  apparently  underlain  extensively  by  sand,  and  is  referred  to  by 
Hershey  as  a  sand  plain.  It  bears  only  slight  resemblance  to  the  deltas 
formed  at  the  terminus  of  eskers  in  other  localities,  for  the  ridges  do  not 
merge  into  the  sandy  plain.     As  suggested  by  Herslie}',  there  was  probabl}' 

I  Am.  Geologist,  Vol.  XIX,  :8!I7,  pp.  I97-20!1,  237-2r.3. 


ESKEKS  OF  TSrORTHWESTERi^  ILLINOIS.  81 

a  lake  in  the  portion  of  the  Pecatonica  Basin  west  from  the  ice  margin,  for 
this  basin  is  open  only  to  the  east,  and  in  all  probability  a  lake  would 
occupy  it  outside  the  edge  of  the  ice  sheet  and  become  expanded  eastward 
with  the  retreat  of  the  ice. 

So  far  as  examined,  nothing  was  found  either  by  Hershev  or  by  the 
writer  to  indicate  that  the  structure  of  this  belt  of  rido-es  differs  from  that 
commonly  displayed  by  eskers.  In  several  of  the  ridges  the  upper  portion 
is  found  to  consist  of  a  coarse  gravel  and  cobble,  but  there  are  other  ridges 
composed  largely  of  sand  and  fine  gravel.  The  pebbles  are  chiefly  lime- 
stone, and  are  largely  of  local  derivation.  Hershey  maintains  that  they 
are  derived  by  direct  wear  from  the  neighboring  ledges  rather  than  as  a 
residue  from  the  till,  but  the  writer  is  inclined  to  question  this  interpretation, 
since  the  structure  of  the  till  and  of  the  eskers  is,  so  far  as  he  has  examined 
in  this  district  as  well  as  elsewhere,  quite  similar  in  the  kind  of  coarse  rock 
ingredients. 

cedarviiie  belt. — Hershey  has  traced  two  other  lines  of  grayelly  drift  for 
several  miles  in  an  east-west  course  in  the  portion  of  Stephenson  County 
north  of  the  belt  just  discussed.  To  these  he  has  given  the  names  Cedar- 
viiie and  Orangeville.  The  former  belt  he  considers  to  have  its  beginning 
in  the  valley  of  Rock  Run,  about  IJ  miles  east  of  Rock  City,  but  it  can 
not  be  definitely  traced  until  it  reaches  the  valley  of  Cedar  Creek,  about  2 
miles  above  Cedarviiie.  It  is  prominently  developed  southeast  of  Cedar- 
viiie, where  it  rises  into  sharp  knolls  80  or  90  feet  in  height,  which  have  so 
obstructed  the  old  valley  of  Cedar  Creek  as  to  compel  the  stream  to  cut  a 
gorge  on  the  north  side  of  the  village.  The  belt  is  again  prominent  near 
the  junction  of  Cedar  and  Richland  creeks,  2  miles  west  of  Cedarviiie.  It 
is  again  prominent  at  the  village  of  Damascus.  The  belt  extends  about  3 
miles  farther  in  a  northwestward  course,  as  a  line  of  shaip  knolls,  the  ter- 
minus being  about  3  miles  northeast  of  the  village  of  Lena.  The  well- 
defined  portion  of  this  belt  is  about  12  miles  in  length,  but  if  we  consider 
its  beginning  to  be  at  Rock  Run,  its  length  is  nearly  20  miles. 

Orangeville  belt. — The  Orangoville  belt  has  been  only  partially  mapped  by 
Hershey,  and  is  found  to  be  best  developed  south  of  the  village  of  Orange- 
ville, and  again  just  north  of  Winslow.     At  the  latter  point  it  rises  into  a 
veiy  prominent  knoll  with  a  number. of  associated  ridges. 
3ION  xxxviii 6 


82  THE  ILLINOIS  GLACIAL  LOBE. 

General  observations. — The  followiug  observatioiis  conceiiiing  the  belts  in 
Stephenson  and  Ogle  counties  are  made  by  Hershey,  in  the  paper  above 
cited: 

(1)  They  are  not  confined  to  any  level,  but  cross  ridges  of  any  lieight,  in  several 
cases  150  feet  or  more  above  the  present  bottom  of  adjoining  valleys.  However,  they 
are  best  developed  at  lower  levels  and  the  most  prominent  knolls  and  ridges  stand  in 
the  center  of  valleys. 

(2)  They  will  not  bend  from  a  direct  course  upon  encountering  a  low  ridge,  but 
are  readily  compelled  to  change  direction  upon  meeting  one  of  the  high  ridges,  which 
constitute  the  remains  of  the  peneplain. 

(3)  When  in  a  narrow  valley  there  is  usually  but  a  single  ridge  and  only  few 
secondary  belts,  but  in  such  a  wide  basin  as  that  of  the  Pecatonica  Eiver  and  Yellow 
Creek,  there  are  a  number  of  parallel  ridges.  ^ 

The  system  of  eskers  of  northwestern  Illinois  indicate  that  the  di-ain- 
age  from  the  ice  sheet  was  somewhat  vigorous,  though  the  combined  bulk 
of  the  gi-avelly  material  contained  in  them  is  but  a.  small  portion  of  the 
di'ift  of  that  region.  It  is  probable  that  they  were  formed  during  the  gen- 
eral recession  of  a  nearly  stagnant  sheet  of  ice.  The  trend  of  the  main 
ridges  is  about  in  line  with  the  supposed  direction  of  the  ice  movement, 
which  is  usually  nearly  at  right  angles  with  the  ice  margin.  Some  of  the 
ridges,  especially  the  Cedarville  belt  and  the  Hazelhurst  esker,  curve  toward 
the  boundary  in  the  western  portions,  changing  from  a  westward  to  a  north- 
westward course.  Whether  the  ice  movement  was  characterized  by  a  cor- 
responding curve  can  scarcely  be  determined,  though  it  seems  a  not 
improbable  movement. 

TRAK^SPOETED   EOCK  LEDGES. 

In  northwestern  Illinois  there  are  several  remarkable  instances  of 
transportation  of  limestone  ledges  which  have  been  discovered  by  Her- 
.shey,-  the  most  of  which  are  indicated  on  PI.  XII.  These  ledges  in  some 
instances  occupy  an  area  of  several  acres.  They  have  been  moved  west- 
ward from  the  crest  of  rock  ridges  without  completelj'  destroying  tlieir 
stratification.  In  most  cases  they  have  been  deposited  at  levels  lower  than 
the  ridges  from  which  they  are  derived  and  rest  upon  glacial  deposits  on 
the  slopes  or  bottom  of  neighboring  valleys,  but  in  some  instances  such 
ledges  have  been  transported  to  points  as  high  as  their  original  position.     It 

■Am.  Geologist,  Vol.  XIX,  1897,  pp.  197-20S,  237-2.53.  -Loc.  cit.,  pp.  245  353. 


TEANSPOETED  EOCK  LEDGES.  83 

seems  necessary  to  call  in  the  action  of  the  ice  sheet  to  account  for  these 
transportations,  for  they  can  not,  as  a  rule,  be  the  result  of  landslides  or  of 
a  slow  creeping  down  the  slope.  Hershey  refers  them  to  the  closing  stage 
of  the  ice  movement,  for  the  reason  that  if  transportation  had  occurred  in 
the  midst  of  the  invasion  the  ledges  would,  in  all  probability,  have  been 
more  thoroughly  intermingled  with  the  drift.  Except  in  a  very  few 
instances  no  drift  pebbles  have  been  found  in  the  body  of  these  deposits. 
There  are  often  bowlders  and  smaller  drift  pebbles  scattered  over  their 
sixrface. 

Hershey  has  also  discovered  places  where  the  ledges  have  been  pressed 
into  slight  folds  Avithout  suffering  transportation.  In  these  folds  the  strata 
show  dips  of  10  to  30  degrees,  while  the  greatest  dips  of  the  strata  due  to 
orographic  bending,  so  far  as  he  has  discovered,  do  not  exceed  2  degrees 
The  reference  of  this  disturbance  to  ice  action  appears  well  sustained.  If 
the  folding  of  the  strata  is  not  due  to  this  agency  it  seems  necessary  to 
refer  it  to  a  remarkable  local  disturbance,  since  the  strata  in  the  surround- 
ing districts  are  practically  horizontal. 

The  transported  and  disturbed  rock  masses  are  especially  numerous  in 
the  township  of  Dakota,  in  Stephenson  County.  Within  4  miles  west  and 
southwest  of  the  village  of  Dakota,  Hershey  has  found  at  least  thirty 
distinct  deposits  of  this  class.  They  are  g-enerally  conical  or  dome-shaped 
masses  a  few  rods  in  diameter,  which  appear  as  though  embossed  on  the 
top  and  slope  of  high  rock  ridges.  When  the  internal  structure  is  revealed 
by  excavations,  the  incoherent  portions  are  found  to  alternate,  both  horizon- 
tally and  vertically,  with  other  portions  in  which  the  original  bedding  planes 
have  been  but  little  disturbed.  Hershey  cites  two  instances  of  the  occur- 
rence of  transported  ledges  in  the  midst  of  valleys  2  or  3  miles  west  of 
Dakota,  in  which  burrowing  animals  have  brought  out  waterworn  gravel 
and  sand  from  under  the  limestone.  The  largest  ridge  is  about  75  feet  high 
and  nearly  obstructs  the  valley  in  which  it  stands.  The  smaller  one  is 
about  30  feet  high  and  is  composed  of  Galena  limestone,  not  much  broken, 
but  with  the  strata  dipping  steeply  in  every  direction  from  the  center  and 
top  of  the  mound.  These  masses  are  scattered  widely  over  Stephenson 
County  east  of  the  meridian  of  Freeport. 

Hershey  has  noted  a  tendency  to  greater  development  of  this  peculiar 
class  of  I'ock  transportation  along  lines  leading  north  and  south  from  the 


84  THE  ILLINOIS  GLACIAL  LOBE. 

strongly  developed  portions  of  the  Pecatonica  esker  belt,  and  this  has  led 
him  to  suggest  that  along  the  lines  where  these  deposits  are  heavily  devel- 
oped there  is  the  culminating  limit  of  some  stage  of  glacial  readvance — a 
suggestion  which  implies  that  the  ice  had  not  reached  an  entirely  stagnant 
condition  at  the  time  the  eskers  were  forming.  The  reader  will  find  in 
Hershey's  discussion  of  these  ridges  a  detailed  account  of  the  several  instances 
of  transported  rock  ledges  which  he  has  examined,  together  with  a  discus- 
sion of  their  probable  mode  of  origin.  So  far  as  known  to  the  writer,  such 
remarkable  transportation  of  rock  ledges  has  not  been  reported  in  other 
localities.  Possibly  the  disturbed  beds  which  pass  horizontally  into  and 
rest  upon  undisturbed  beds,  have  been  wrinkled  in  post-glacial  time  in  the 
manner  suggested  by  Gilbert  for  the  somewhat  similar  phenomena  in  New 
York,  and  which  find  illustration  also  in  northeastern  Ohio.^ 

GLACIAL    strips;. 

Striae  have  been  found  not  only  in  the  interior  portion  of  the  district 
covered  by  the  Illinois  lobe  but  also  in  several  instances  near  the  extreme 
borders.  The  latter  usually  bear  directly  toward  the  drift  border.  Thus 
in  western  Illinois  the  bearing  is  westward,  in  southwestern  Illinois  south- 
westward,  in  southern  Illinois  southward,  and  in  western  Indiana  southeast- 
ward, as  appears  on  the  glacial  map,  PI.  VI.  The  striae  in  southeastern  Iowa 
present  an  apparent  exception,  there  being  several  eastward  and  but  one 
westward  bearing  observed.  But  it  should  be  remembered  that  that  district 
was  covered  prior  to  the  Illinoian  invasion  by  another  ice  lobe  which 
deployed  eastward  across  southeastern  Iowa,  and  it  is  to  that  ice  lobe  that 
the  eastward-bearing  striae  are  referred. 

There  are  wide  areas  in  this  region  where  striae  have  not  been  discov- 
ered. The  absence  of  observations  does  not  imply  that  the  ledges  are  not 
striated,  for  too  Uttle  attention  has  been  given  the  rock  surfaces  to  insure  a 
complete  mapping.  It  is  probable  that,  many  more  instances  will  be 
reported  as  detailed  investigations  are  carried  on.  There  are,  however, 
extensive  areas  in  which  no  rock  exposures  occur,  and  other  areas  in  which 
the  surface  rocks  are  of  such  character  as  to  break  down  quickly  upon 
exposure,  so  that  striae  can  scarcely  be  preserved.     This  condition  is  found 

'Proc.  Am.  Assoc.  Adv.  Sci.,  Vol.  XXXV,  1886,  p.  227.     Also  Vol.  XL,  1891,  pp.  249,  250.     (See 
also  Hull.  Geol.  Soc.  Amer.,  Vol.  X,  1890,  pp.  l.Sl-134.) 


GLACIAL  STEI.i:.  _  85 

not  only  in  the  sandy  shales  of  the  Coal  Measures  but  also  in  a  large  part 
of  the  area  immediately  underlain  by  limestone.  The  Galena  limestone, 
for  example,  has  scarcely  ever  afforded  exposures  of  striation  in  its  exten- 
sive outcrops  in  Stephenson,  Jo  Daviess,  Ogde,  and  Carroll  counties,  for 
its  surface  is  usually  so  rotten,  even  under  the  deepest  deposits  of  till,  that 
strise  would  not  be  preserved. 

In  not  a  few  instances  the  ice  sheet  is  found  to  have  failed  to  remove 
the  residuary  clays  which  overlie  the  bed  rock,  and  in  such  instances  strise, 
of  course,  were  never  formed.  How  extensively  the  surface  ledges  escajDed 
striation  is  not  known,  but  the  present  knowledge  of  rock  exposures  within 
the  glaciated  portion  of  the  Mississippi  Basin  leads  the  writer  to  think  that 
a  large  percentage  of  the  rock  surface  never  was  striated. 

A  few  of  the  strife  on  the  border  of  the  lobe  merit  sj^ecial  notice.  At  the 
city  of  Burlington,  Iowa,  strise  formed  both  by  the  Illinois  glacial  lobe  and 
by  the  southern  extension  of  the  Keewatin  ice  sheet  are  present.  Onlj"  one 
instance,  however,  has  been  found  in  which  the  strije  on  the  Iowa  side  are 
certainly  referable  to  the  Illinoian  ice  sheet.  This  exposure  occurs  at  the 
northeast  corner  of  the  intersection  of  Court  and  Prospect  streets,  in  the 
north  part  of  Burlington,  and  was  the  joint  discovery  of  Mr.  F.  M.  Fultz 
and  the  writer.  The  bearing  is  S.  72°  W.,  and  satisfactory  evidence  is 
found,  from  prominences  on  the  striated  ledge,  that  the  movement  was 
westward  and  not  eastward.  Strise  were  discovered  by  the  writer  on  the 
east  bluflF  of  the  Mississippi,  opposite  Burlington,  which  have  a  nearly  due 
east-west  bearing.  In  this  exposure  the  evidence  concerning  the  direction 
of  movement,  whether  eastward  or  westward,  is  not  decisive,  there  being 
no  prominences  on  the  ledge  which  would  throw  light  on  the  direction  of 
movement.  The  bearing  harmonizes  more  easily  with  a  westward  move- 
ment than  an  eastward  movement,  and  the  balance  of  probabilities  seem  in 
favor  of  westward  movement. 

The  strife  due  to  the  earlier  or  Keewatin  ice  lobe,  both  in  Burlington 
and  at  other  points  north  of  the  city  reported  by  Mr.  Fultz,  have  a  bearing 
generally  about  S.  65°-70°  E.,  their  direction  being  about  the  same  as  that 
of  strias  found  by  the  writer  near  Washington,  Iowa,  and  by  Professor 
Cahdn  in  the  vicinity  of  Iowa  City.  One  localit}^,  however,  was  found 
in  quarries  one-half  mile  north  of  West  Burlington,  in  which  the  bearing 


86  THE  ILLINOIS  GLACIAL  LOBE. 

is  very  nearly  west  to  east.  The  prominences  on  the  rock  ledge  appear  to 
sustain  the  eastward  rather  than  the  westward  direction  of  movement,  but 
they  are  so  slight  that  some  distrust  of  this  interpretation  is  felt.  The 
harmony  with  the  westward-bearing  striae  and  lack  of  harmony  with  the 
eastward  would  be  in  favor  of  their  classification  with  the  former.  It 
will  be  noted  that  two  exposures  north  of  Burlington  are  eccenti'ic  in 
showing  bearings  S.  only  15°  and  33°  E.  All  the  striae  in  the  vicinity  of 
Burlinsrton  are  found  at  elevations  100  feet  or  more  above  the  level  of  the 
Mississippi,  or  at  about  the  general  level  of  the  higher  portions  of  the  rock 
surface. 

The  glacial  origin  of  certain  striae  at  Alton,  Illinois,  has  been  called  in 
question  by  Prof  J.  E.  Todd.^  The  striae  first  seen  at  that  city  occur 
beneath  a  culvert  on  Piasa  street,  in  a  small  valley  near  the  round  house  of 
the  Chicago  and  Alton  Railway,  at  a  level  perhaps  30  feet  lower  than  the 
higher  pai't  of  the  rock  ledges  of  the  immediate  vicinity.  Todd  has  expressed 
the  view,  in  the  paper  just  cited,  that  these  striae  were  produced  by  a  hori- 
zontal slipping  of  rock  ledges,  and  that  they  are  now  exposed  tlu-ough  the 
removal  of  ledges  which  once  covered  them.  Numerous  exposures  of  slick- 
ensides  and  slight  faults  appear  in  that  vicinity,  showing  that  it  is  a  district 
where  disturbances  have  occurred.  He  recognized,  as  has  the  writer,  that 
the  striae  bear  a  strong  resemblance  to  glacial  striae,  but  as  glacial  striae  and 
slickensides  are  both  produced  by  the  movement  of  rock  upon  rock,  he 
urged  that  the  resemblance  to  glacial  striae  does  not  forbid  their  being  con- 
sidered slickensides.  Since  the  appearance  of  Todd's  paper  the  writer  has 
reexamined  this  ledge  and  found  satisfactory  evidence  that  the  striae  are  not 
slickensides.  The  striation  occurs  on  three  different  layers  of  surface  rock. 
Now,  if  it  was  produced  by  rock  ledge  slipping  upon  rock  ledge,  we  should 
expect  the  striation  to  occur  between  these  layers  as  well  as  on  their  exposed 
siu-faces,  but  an  examination  showed  that  the  striation  is  confined  to  the 
exjDosed  surfaces,  and  that  the  striating  agency  must  have  been  such  as 
could  affect  only  the  exposed  surfaces. 

Furthermore,  following  the  Chicago  and  Alton  Railway  track  north- 
ward from  tliis  exposure,  two  other  striated  surfaces  were  found  at  levels 

'  stria)  and  slickensides  at  Alton,  Illinois,  by  J.  E.  Todd :  Proc.  Am.  Assoc.  Adv.  Sci.,  Vol.  XL,  1891, 
pp.  254, 255. 


GLACIAL  STRIDE.  87 

about  as  high  as  are  reached  by  the  hmestone  in  that  vicinity.  These 
surfaces  had  been  exposed  by  the  removal  of  till  in  the  railway  cuttings 
and  were  overlain  by  several  feet  of  unmodified  till.  The  glacial  origin  of 
these  striae  seems  supported,  therefore,  by  the  character  of  the  striation,  the 
position  of  the  striae,  and  the  character  of  the  overlying  beds. 

The  striae  observed  by  Prof  G.  F.  Wright  in  Jackson  and  Williamson 
counties,  Illinois,  are  the  southernmost  ones  yet  foimd  in  the  drift-covered 
region  of  eastern  North  America.  Wright  states  that  the  glaciation  is  as 
heavy  as  is  often  found  at  points  some  distance  within  the  glacial  boundary. 
They  are  scarcely  more  than  5  miles  from  the  extreme  limit  of  glaciation, 
and  bear  directly  toward  the  glacial  boundary.  Those  noted  by  the  writer 
a  few  miles  northwest  from  Murphysboro  are  also  very  heavy  glacial 
grooves  and  are  situated  equallj'  near  the  glacial  boundary. 

The  striae  in  Greene  and  Owen  counties,  Indiana,  are  usually  found  on 
a  firm  sandstone.  Those  observed  by  the  writer  near  Worthington  are 
heavy  grooves.  The  character  of  the  glaciation  at  points  reported  by  other 
observers  appears  from  descriptions  to  be  as  vigorous  as  at  the  points  just 
considered.  The  remarkable  variation  in  bearing  in  Owen  County  is 
worthy  of  further  investigation. 

The  bearings  of  the  sti'iae  in  the  vicinity  of  the  Wabash  Valley  in 
Clark  County,  Illinois,  and  in  Vigo  and  Sullivan  counties,  Indiana,  give 
rise  to  some  sm-prise,  for  the  striae  appear  to  show  no  disposition  to  radiate 
toward  the  neighboring  portion  of  the  glacial  boundary  on  the  southeast. 
Dr.  J.  T.  Scovell,  who  made  all  these  observations  in  the  vicinity  of  the 
Wabash,  reports  that  there  is  heavy  glaciation  at  each  exposure. 

In  the  list  of  striae  given  below  four  exposures  are  reported  from 
northern  Illinois  which  are  situated  within  the  limits  of  the  lowan  drift.  It 
is  not  certain  whether  they  were  produced  at  the  lowan  invasion  or  at  the 
lUinoian,  They  appear  to  be  in  harmony  with  the  general  movement  of 
the  ice  sheet  at  the  Illinoian  stage  as  well  as  at  the  lowan.  These  exposures  , 
were  in  each  case  first  observed  and  reported  by  Mr.  I.  M.  Buell,  and  are 
said  to  be  very  faint  compared  with  the  striae  seen  by  him  within  the  limits 
of  the  Wisconsin  invasion.  The  list  given  below  is  restricted  to  the  district 
outside  the  Wisconsin  drift,  the  striae  within  the  limits  of  the  latter  drift 
being  included  in  a  table  presented  later  (pp.  412-414). 


88 


THE  ILLINOIS  GLACIAL  LOBE. 

Table  of  strim  outside  the  Shelhyville  moraine. 


Location. 

Bearing. 

Observer. 

Near  Wiimebno'o  III    at  quarry  in  sfc.  6  T.  26,  R.  11  E   

S.75°W 

Buell. 

Blufif  of  Rents  Creek  near  Kockford,  111.,  two  esposure.s,  sees. 

S.75°W 

Do. 

28  and  29,  T.  44,  E.  1  E. 

Cutting  on  Chicago,  Jlilwaukee  and  St.  Paul  Railroad,  west 

S.65°W 

Do. 

of  Fielding,  111. 

Cutting  on  Chicago,  Milwaukee  and  St.  Paul  Railroad,  east  of 

S.75°W 

Do. 

Fielding,  111. 

East  bluff  of  Mississippi  near  Gladstone,  111  .... 

S.79°W 

Leverett. 

S.72°W 

Leverett  &  Fultz. 

North  Hill,  Burlington,  Iowa 

S.65°E 

Leverett. 

W.-E 

S.75°E 

S.73°E 

S.33°E 

S.15°E 

S.64°E 

Do. 
Fultz. 

Do. 

Do. 
C.  A.  White. 
Fultz. 

Do               

Near  Kingston,  Des  Moines  County,  Iowa.     Main  set  of  striie. 

(Scattering  striie  S.  30-  15'  E.,  S.  60°  30'  E.,  S.  72°  15'  E.) 

One-half  mile  from  preceding 

S.  70°  E.  ±  . . 

Do. 

Five  miles  north  of  Hamilton,  111.,  line  of  sees.  4  and  5,  T.  5, 

S.65°E 

Leverett. 

E.  8  W. 

West  of  Havana,  111.,  in  sec.  6,  T.  3  N.,  R.  3  E   

S.  103°W.... 

S.40°W 

S.30°-40°W. 

Do. 
Do. 
Do. 

Alton,  111.,  on  Piasa  street           

Cuttings  on  Chicago  and  Alton  Railroad,  north  of  Alton 

Six  miles  northwest  of  Murphyshoro,  sec.  10,  T.  8,  R.  3  W 

S.30°W 

Do. 

S.5°W 

S.  10°-15°  E  . 

S.20°AV 

South 

G.  F.  Wright. 

Do. 
Scovell. 

Do. 

Two  miles  northeast  of  Marshall,  111 

Two  miles  southea.st  of  Farmersburg,  Ind 

Southeastern  part  of  Linton  township,  Vigo  County,  Ind 

South 

Do. 

Northern  part  of  Linton  township  (sec.  3) 

S.20"W 

S. 72°  E 

Do. 
Leverett. 
Collett  A-  Brown. 
Siebenthal. 

Do. 

Two  miles  south  of  Putnamville 

N.-S 

S.80°E 

S.  18°  E 

Sec.  6,  T.  7,  R.  4  W.,  Greene  County,  Ind 

Three  miles  south-southwest  of  Vandalia,  lud  .... 

W.-E 

S.  40°-50°  E  . 

Wright. 
Do. 

'  Collett. 

Five  miles  west  from  preceding 

Near  Bowling  Green,  lud.,  sec.  19,  T.  11,  R.  5  W 

|S.26°30'E  .. 
'lS.30°35'E.. 
|S.26°30'E.. 
is.  29°  30' E.. 

Sec.  35,  T.  11,  R.  6W 

Sec.  6,  T.  11,  R.  5  W 

S.  26°  30'  E  . . 

Do 

S.  34°  E 

Leverett. 
Collett. 
Do. 
Jenkins. 

Do 

S.  36°  56'  E 

Three  miles  south-south  west  of  Bowling  Green 

S.  32°  10' E.. 
S.  0°  35'  W  . . 

Near  Cloverdale,  lud 

THE  illinoia:n^  drift  sheet.  89 

EFFJECT  OF  THE   ILEINOIAN    ICE   INVASION   0]S^   THE   OFTER-BOEDEE 

DEAIKAGE. 

A  most  important  question  connected  with  the  lUinoian  invasion  is  its 
effect  upon  the  di-ainage  hues  of  the  border  districts.  The  slope  of  the 
region  west  of  its  western  border  in  Iowa  is  directly  toward  that  border, 
and  the  large  streams  had  apparently  opened  channels  to  about  the  present 
line  of  the  Mississippi  prior  to  the  invasion  of  this  ice  sheet.  The  ice 
nowhere  extended  more  than  20  miles  beyond  the  present  valley  of  the 
Mississippi,  but  it  covered  that  valley  for  a  distance  of  over  100  miles.  It 
apparently  furnislied  an  obstruction  of  such  consequence  that  the  question 
of  a  more  or  less  complete  displacement  of  the  main  artery  of  drainage 
naturally  suggests  itself. 

On  the  southwest,  below  Keokuk,  Iowa,  the  ice  sheet  failed  to  cover 
the  Mississippi  and  the  obstruction  to  the  drainage  disappears.  At  the  south 
the  terminus  was  near  the  crest  of  the  elevated  ridge  that  crosses  southern 
Illinois,  and  no  streams  discharged  toward  the  ice  margin.  On  the  south- 
east a  part  of  the  border  touches  an  elevated  tract,  whose  natural  course  of 
drainage  appears  to  have  been  toward  the  ice  margin.  The  amount  of  drain- 
age obstruction  in  that  region  becomes,  therefore,  an  important  question. 

TEMPORARY  DISPLACEMENT   OF  THE  MISSISSIPPI. 

That  the  Illinoian  ice  invasion  did  not  permanently  displace  the  portion 
of  the  Mississippi  which  it  covered  is  certain,  for  a  considerable  section  of 
the  present  course  of  the  stream  crosses  the  territory  covered  by  the  Illi- 
noian drift.  Furthermore,  this  section  of  the  river  follows,  in  the  main,  the 
line  of  a  preglacial  valley  which  appears  to  have  been  the  main  artery  of 
drainage  for  this  region  down  to  the  time  of  the  Illinoian  invasion,  except 
perhaps  during  the  Kansan  invasion.  The  rapids  between  Montrose  and 
Keokuk,  12  miles  in  length,  and  the  rapids  and  narrow  portion  of  the 
Mississippi  Valley  between  the  mouth  of  the  Wapsipinnicon  and  Muscatine, 
40  miles  in  length,  are  the  only  departures  made  by  the  river  from  the  line 
of  broad  preglacial  valleys.  The  latter  displacement  is  not  such  as  to 
coincide  with  the  border  of  the  Illinoian  drift,  and  was  apparently  not 
determined  by  this  invasion.  There  remains,  then,  but  the  stretch  of  12 
miles  at  the  lower  rapids,  in  which  the  present  stream  has  opened  a  new 
course,  that  even  approximately  coincides  with  the  Illinoian  di'ift  border. 


90  THE  ILLINOIS  GLACIAL  LOBE. 

But  turning  from  the  question  of  a  permanent  displacement  to  that  of  a 
temporary  one,  the  influence  of  the  Illinoian  invasion  becomes  more  appar- 
ent. Several  years  ago  the  writer  found  a  large  abandoned  valley  in  Lee 
County,  Iowa,  shown  in  fig.  4  (p.  468),  which  leads  southeastward  across  the 
county  from  Big  Cedar  Creek,  a  tributary  of  Skunk  River,  to  the  Mississippi 
River,  which  it  joins  about  6  miles  below  Fort  Madison.  This  large  valley 
is  now  occupied  for  a  few  miles  by  East  Sugar  Creek,  a  small  tributary  of 
the  Mississippi.  This  aliandoned  valley  was  at  first  supposed  to  have  been 
the  former  course  of  Big  Cedar  Creek,  which  now  makes  a  singular  deflec- 
tion to  the  north,  near  its  mouth,  and  this  interpretation  was  published  in 
1885.^  A  few  years  later  (in  1894)  the  writer  began  systematic  investiga- 
tions in  southeastern  Iowa  and  found  evidence  that  the  valley  has  a  con- 
tinuation northward  from  Lee  County  along  the  north-flowing  portion  of 
-Cedar  Creek  past  Skunk  River,  the  present  valle}"  of  that  stream  being 
along  it  for  a  few  miles  above  the  village  of  Rome,  in  Henry  County.  The 
study  that  season  did  not  develop  evidence  of  the  further  continuation  of 
the  valley.  But  in  1896  the  district  between  the  Skunk  and  Iowa  rivers 
was  examined,  to  determine  whether  the  upper  Mississippi  with  its  western 
tributaries  did  not  utilize  this  abandoned  valley  during  the  Illinoian  invasion. 
This  study  resulted  in  the  discovery  of  an  abandoned  channel  which  leaves 
the  Iowa  River  just  north  of  Columbus  Junction  and  passes  southward  imme- 
diately outside  the  limits  of  the  Illinoian  diift  to  the  valley  of  Crooked  Creek 
near  Winfield,  and  thence  westward  to  Skunk  River  along  a  double  channel, 
the  northern  one  being  now  occupied  by  Crooked  Creek,  while  the  southern 
is  only  partially  occupied  by  a  stream.  It  thus  appears  that  the  waters  of 
the  Iowa,  with  its  main  tributary.  Cedar  River,  as  well  as  of  Skunk  River 
and  Big  Cedar  Creek,  have  followed  this  abandoned  channel  southward 
around  the  western  edge  of  the  Illinoian  drift.  To  complete  the  connection 
at  the  north  and  show  that  the  Mississippi  follows  this  channel  it  was  only 
necessary  to  utilize  results  already  obtained  by  W  J  McGee  and  J.  A.  Udden. 
Professor  Udden  three  or  four  years  previously  conceived  the  idea  that  the 
Mississippi,  either  in  preglacial  or  in  interglacial  time,  had  taken  a  south- 
westward  course  from  the  Wapsipinnicon  to  Cedar  River,  through  a  broad 
sag  now  drained  in  opposite  directions  by  streams  each  of  which  is  called 

'The  deflection  of  Big   Ced.ar  Creek,  by  Frank  Leverett:  The  Aurora,  Iowa  AgrT    College 
Monthly,  November,  1885. 


TEMFORAET  DISPLACEMENT  OF  THE  MISSISSIPPI.  9] 

Mud  Creek.  The  sag  leaves  the  Wapsipmnicon  a  few  miles  east  of  Dixon 
and  comes  to  the  Cedar  River  at  its  bend  near  Moscow,  passing  just  west 
of  Durant  and  through  Wilton.  Its  course  may  be  seen  by  reference  to 
the  Durant  and  Wilton  Junction  sheets  of  this  Survey.  The  north  end  of 
this  portion  of  the  valley  was  occupied  by  the  lowan  ice  sheet,  which  has 
in  a  measure  concealed  its  erosion  contours,  though  the  valley  may  still  be 
traced  without  difficulty.  It  is  now  thought  to  have  been  utilized  by  the 
Mississippi  at  the  Illinoian  stage  of  glaciation. 

The  point  at  which  the  Mississippi  was  deflected  into  this  old  channel 
was  probably  at  the  mouth  of  the  Maquoketa  (see  glacial  map,  PI.  VI),  from 
which  point  it  had  southward  course  through  the  Goose  Lake  channel, 
brought  to  notice  by  McGee\  to  the  Wapsipinnicon,  coming  to  that  valley 
near  the  mouth  of  the  Wapsipiimicon,  as  may  be  seen  by  reference  to  the 
topographic  map  of  that  region,  PI.  XVIII  (in  pocket).  Perhaps  the  Missis- 
sippi also  occupied  its  present  channel  from  the  mouth  of  the  Maquoketa  to 
the  mouth  of  the  Wapsipinnicon.  The  only  apparent  objection  to  this  view 
is  the  possibility  that  the  Illinoian  ice  sheet  obstracted  the  present  course  of 
the  river.  This  being  a  region  in  which  the  lowan  invasion  obliterated  the 
marginal  features  of  the  Illinoian  drift  it  becomes  a  difficult  matter,  as 
already  noted,  to  determine  the  jDi'ecise  position  of  the  Illinoian  boundary. 
It  probably  encroached  but  a  few  miles  at  most  on  the  Iowa  side  of  the 
river  above  the  mouth  of  the  Wapsipinnicon. 

This  abandoned  course  of  the  Mississippi  can  be  studied  to  best  ad- 
vantage in  the  portion  south  from  the  Iowa  River,  as  the  northern  portion 
has  been  greatly  modified  by  the  lowan  ice  invasion.  The  description, 
therefore,  begins  at  the  point  where  the  old  channel  departs  from  the  Iowa 
River.  As  above  noted,  the  course  of  the  chaniiel  is  southward  from  just 
above  Columbus  Junction  to  the  vicinity  of  Winfield,  a  distance  of  12 
miles,  crossing  Long  Creek,  a  small  tributary  of  the  Iowa,  about  6  miles 
south  of  Columbus  Junction.  The  bed  of  the  old  channel  is  about  120 
feet  above  the  level  of  the  Iowa  River  bottom  at  Columbus  Junction,  or 
very  nearly  710  feet  above  tide.  It  is  cut  to  a  depth  of  25  to  35  feet  below 
the  bordering  plain,  and  has  a  width  of  1^  to  1^  miles.  Its  depth  and 
breadth  are  not  much  greater  than  that  of  the  present  Mississippi  within  its 

'The  drainage  systems  and  loess  of  eastern  Iowa,  by  W  J  McGee,  private  publication,  1884. 
Also  the  Pleistocene  history  of  northeastern  Iowa,  by  W  J  McGee,  Eleventh  Ann.  Rept.,  U.  S.  Geol, 
Survey,  1891,  pp.  227,  228. 


92  THE  ILLINOIS  GLACIAL  LOBE. 

banks,  and  it  has  the  appearance  of  being  a  stream  channel  or  bed  rather 
than  a  valley  proper,  the  only  flood  plain  being  the  bordering  uplands.  A 
fine  view  of  the  valley  may  be  obtained  just  west  of  Colum])us.  Before 
reaching  Winfield  a  channel  branches  off  to  the  west  from  the  main  channel 
and  joins  it  again  just  south  of  Wyman.  This  channel  has  a  breadth  of 
but  one-eighth  mile  or  less.  It  is  more  dh-ect  than  the  main  channel,  and 
has  about  the  same  depth.  ♦ 

A  short  distance  east  of  Winfield  the  main  channel  is  entered  from 
the  east  by  the  East  Fork  of  Crooked  Creek,  and  this  stream  meanders 
tlu'ough  the  broad  bottom  of  the  main  channel  westward  to  its  junction 
with  the  West  Fork,  and  thence  continues  west  and  south  to  Skunk  River 
Valley  at  Coppock.  Another  channel  leads  directly  west  from  Winfield 
past  Wayne  to  Coppock,  a  distance  of  15  miles.  The  combined  width  of 
the  two  channels  is  but  little  greater  than  that  of  the  portion  of  the  channel 
north  from  Winfield,  the  channel  along  Crooked  Creek  being  about  three- 
fourths  to  1  mile  in  width  and  the  channel  leading  past  Wayne  one-fourth 
mile.  The  lower  portion  of  Crooked  Creek  nearly  occupies  the  full  width 
of  the  north  channel,  but  throughout  the  greater  part  of  the  course  it  is 
bordered  by  a  broad  terrace-like  plain,  several  times  the  breadth  of  the 
valley  which  it  has  excavated.  The  depth  of  about  25  to  35  feet  continues, 
as  in  the  portion  north  from  AVinfield. 

The  portion  along  Skunk  River  from  Coppock  to  Rome,  a  distance  of 
10  miles,  is  so  completely  occupied  by  the  valle}"  of  that  river  that  only 
occasional  narrow  remnants  of  the  abandoned  channel  appear  as  terraces 
on  its  borders,  the  average  breadth  of  that  part  of  Skunk  River  Valley 
being  fully  1  mile.  The  most  extensive  remnant  of  the  abandoned  channel 
is  found  in  the  double  oxbow  made  b}'  the  river  north  and  west  from  the 
village  of  Rome,  which  stands,  where  not  broken  down  by  subsequent 
erosion,  about  67()  to  675  feet  above  tide. 

From  Rome  the  abandoned  valley  continues  southward  along  the 
valley  of  Big  Cedar  Creek  (reversed)  and  is  iireserved  in  terracelike  rem- 
nants on  each  borchn-  of  the  valley  which  stand  30  feet  or  iiiore  below  tlie 
level  of  the  ujjland  jilain.  The  average  l)readth  of  the  valley  being  not 
less  than  one-half  mile  the  terrace  renmants  are  narrow.  From  the  bend  of 
the  Big  Cedar,  S  miles  south  of  Rome,  tlic  old  valley,  as  noted  above,  leads 
southeastward  across  Lee  County  to  the  Mississippi  Valley  at  Viele,  6  miles 
below  Fort  Madison,  gradually  deepening  from  30   feet  at  the  north  to  50 


TEMPOKARY  DISPLACEMENT  OF  THE  MISSISSIPPI.  93 

or  60  feet  at  the  south.  It  is  occupied  for  about  4  miles  by  Little  Cedar 
Creek  just  south  of  the  bend  of  Big  Cedar.  The  remainder  of  its  course  is 
drained  by  Sugar  Creek.  The  excavation  along  the  channel  from  Columbus 
Junction  to  Viele  is  estimated  to  be  one-half  a  cubic  mile. 

Tlie  precise  elevation  of  the  bottom  of  this  old  channel  has  been  deter- 
mined at  only  a  few  points  in  the  portion  south  from  Columbus  Jvniction. 
.The  elevation  at  the  border  of  the  Iowa  River  12  miles  north  of  Winfield 
is  apparently  not  more  than  710  feet.  At  Winfield  its  elevation  is  about  10 
feet  below  the  railway  station  or  703  feet  above  tide.  The  altitude 
appears  to  fall  but  little  in  the  15  miles  between  Winfield  and  Skunk  River. 
The  aneroid  determinations  made  at  Coppock  give  the  old  channel  an  alti- 
tude of  about  700  feet  above  tide.  In  the  oxbow  near  Rome  the  altitude  is 
about  675  feet.  At  the  point  where  the  Keokuk  and  Northern  Railroad 
crosses  the  channel,  near  the  line  of  Henry  and  Lee  counties,  the  elevation 
is  657  feet.  At  St.  Paul  station  on  tlie  Fort  Madison  and  Des  Moines  Rail- 
road 5  miles  southeast,  tlie  elevation  is  645  feet,  and  at  the  point  where  the 
channel  joins  the  Mississippi,  14  miles  farther  southeast,  about  620  feet. 
The  distance  from  the  jioint  where  this  channel  leaves  the  Iowa  River  to 
its  junction  with  the  Mississippi  is  about  75  miles.  The  fall  of  90  feet 
which  it  makes  in  this  distance  would  therefore  give  an  average  of  slightly 
more  than  1  foot  a  mile.  The  fact  if  it  be  proved  that  the  channel  has  no 
tall  in  the  portion  leading  west  from  Winfield  may  bring  support  to  the 
hypothesis  suggested  by  studies  farther  north  that  the  surface  has  been  sub- 
jected to  a  westward  differential  uplift  in  the  later  part  of  the  Pleistocene.^ 
The  measurements  of  altitude,  however,  are  not  sufficiently  exact  to  justify 
the  presentation  of  these  data  in  support  of  the  hypothesis. 

The  writer  has  been  unable  to  discover  any  notable  amount  of  sand  or 
gravel  in  the  bed  of  this  channel.  It  generally  appears  to  be  swept  clean 
of  such  deposits.  The  valley  is  coated  with  a  sheet  of  loess  similar  to  that 
which  occurs  on  the  bordering  uplands,  but  this  deposit  is  apparently  as 
late  in  deposition  as  the  lowan  stage  of  glaciation,  in  which  case  it  can  not 
be  considered  as  a  deposit  of  the  stream  which  formed  this  channel.  In 
northwestern  Lee  County  sand  to  a  depth  of  10  to  20  feet  is  found  along 
the  channel.  Chamberlin  has  suggested  that  the  ground  in  which  this> 
channel  was  excavated  may  have  been  frozen  at  the  time  of  the  Illinoian 
glaciation,  its  situation  being  on  the  immediate  border  of  the  ice  sheet,  and 

'  See  Chamberlin :  Third  Ann.  Rept.  U.  S.  Geol.  Sui-vey,  p.  391. 


94  THE  ILLIJSOIS  GLACIAL  LOBE. 

the  frozen  condition  of  the  ground  may  have  prevented  the  stream  from 
eroding  more  material  than  it  could  readily  transport.  In  that  case  the 
material  should  be  accumulated  in  portions  of  the  Mississippi  Valley  to  the 
south,  where  the  gradient  became  too  low  to  admit  of  its  being  swept  along. 
In  apparent  support  of  this  view  there  is  found,  immediately  below  the  Des 
Moines  or  lower  rapids  of  the  Mississippi,  a  marked  filling  of  the  valley 
with  deposits  of  sand  and  fine  gravel.  This  filling  may  be  seen  to  good 
advantage  at  and  below  the  village  of  Warsaw,  which  stands  on  a  terrace 
of  aggradation  antedating  the  loess  in  its  formation  and  apparently  sepa- 
rated from  the  Kansan  glacial  stage  by  an  erosion  interval  of  considerable 
length. 

The  Warsaw  exposures  were  examined  by  the  writer  in  1894  and 
reexamined  by  Professor  Chamberlin,  Dr.  H.  F.  Bain,  and  the  writer  in 
the  summer  of  1896,  when  the  relationships  given  above  were  worked  out. 
The  Kansan  till  has  suffered  erosion  to  a  level  but  little  above  the  present 
stream  and  a  bowlder  bed  marks  the  junction  of  this  till  with  the  overlying 
sand  and  gravel.  This  bowlder  bed  is  continued  on  the  north  side  of  the 
river  in  Keokuk,  as  pointed  out  by  Prof  C.  H.  Gordon.^  The  sand  and 
gravel  deposits  are  typical  fluvial  material  and  are  built  up  to  a  height  of 
about  80  feet  above  the  river.  At  their  top  is  an  ashy  silt  resembling  a  soil 
but  perhaps  redeposited  as  flood-plain  material,  and  above  this  a  deposit  of 
sand  grading  upward  into  loess,  the  sand  and  loess  together  being  20  to  25 
feet  in  thickness.  Opposite  Warsaw  near  the  mouth  of  the  Des  Moines 
River  there  is  a  somewhat  different  exposure  of  fluvial  filling  known  as  the 
"  Yellow  banks."  This  has  been  examined,  both  by  the  writer  and  by  Pro- 
fessor Gordon,  and  the  following  section  was  published  in  the  Geology  of 
Iowa  in  1895:' 

"  Yellow-banks"  section,  near  Keokuk,  loioa. 

Ft.     in. 

Clay,  yellow,  pebbleless 5 

Silt,  drab,  pebbleless 1     3 

Eurtb,  black,  with  a  few  small  pebbles ;  apparently  an  old  flood-plaiu  deposit .•        12 

Chiy,  yellowish  (local) 6 

Sand,  with  a  few  small  pebbles;  layers  of  bowlders  1  loot  thick  at  base 20-25 

Earth,  bliick,  with  yellow  streaks;  apparently  an  old  flood-plain  deposit 3-  6 

Gravel,  with  some  sand  beds ;  pebbles  2  inches  or  less  in  diameter  20 

Bine  clay,  till,  exposed 15 

Total 7 85 

1  Iowa  Gool.  Survey,  Vol.  Ill,  1895,  pp.  252-254.  '  Op.  cit.,  p.  243. 


>^^.,"-  *.^' 


96  THE  ILLINOIS  GLACIAL  LOBE. 

deposits  of  sand  and  silt  that  seem  referable  to  the  valley  filling  at  the 
lUinoian  stage  of  glaciation  and  which  antedate  the  loess  by  a  long  period, 
as  shown  by  weathering.  The  surface  of  the  sand  presents  a  deep  red  stain 
to  a  depth  of  3  or  4  feet  below  the  base  of  the  loess,  and  contrasts 
strongly  in  color  and  weathering  with  the  sand  at  greater  depth  as  well  as 
with  the  overlying  loess.  The  weathered  zone  here  is  apparently  the  cor- 
relative of  the  black  earth  found  below  the  loess  at  the  "  Yellow  banks." 
Excellent  exposures  of  this  weathered  zone  may  be  seen  at  the  corner  of 
Second  and  Tiniea  streets  in  Keokuk. 

Examinations  have  been  extended  down  the  IMississippi  on  the  Illinois 
side,  and  it  is  found  that  the  altitude  of  the  valley  tilling  decreases  more 
rapidly  than  the  fall  of  the  present  stream.  At  a  point  opposite  Hannibal, 
^Missouri,  where  Hadley  Creek  enters  the  valley  from  the  east,  the  filling 
reaches  a  level  only  15  or  20  feet  above  the  broad  bottom  of  the  Mississippi 
or  scarcely  35  feet  above  the  stream,  and  about  90  feet  below  its  altitude 
at  Warsaw,  45  miles  up  the  valley.  This  rapid  increase  in  the  amount  of 
filling  apparently  supports  the  view  that  material  was  swept  into  the  valley 
and  there  deposited  in  delta-like  fashion. 

Returning  to  the  discussion  of  the  abandoned  channel,  and  taking  up 
the  portion  northeastward  from  the  Iowa  River,  it  is  found  that  it  has 
slightly  lower  altitude  than  the  portion  in  the  district  south  from  the  Iowa 
River,  much  of  it  being  below  700  feet  above  tide.  In  explanation  of  this 
lower  altitude  it  is  suggested  that  the  section  to  the  north  of  the  Wapsipin- 
icon  River  and  possibly  the  portion  between  the  Wapsipinicon  and  Iowa 
rivers  may  have  been  occupied  by  the  Mississippi  for  a  considerable  period 
after  the  southern  portion  had  been  abandoned.  Possibly  it  persisted  in  the 
occupancy  of  its  channel  until  the  lowan  ice  invasion  forced  it  out. 

The  broad  valley  of  the  southwestward  flowing  portion  of  the  Cedar 
appears  to  have  held  a  lake  at  the  Illinoian  stage  of  glaciation  for  which 
Udden  has  recently  suggested  the  name  "Lake  Calvin."  The  features  of 
this  old  lake  bed  are  discussed  by  Udden  in  a  report  on  the  geology  of 
Muscatine  County,  Iowa.' 

The  abandonment  of  the  lower  end  of  the  channel  from  Columbus 
Junction  southward  probably  occurred  as  soon  as  the  ice  sheet  had  with- 
drawn sufficiently  to  uncover  the  present  line  of  the  stream,  for  the  altitude 

I  Iowa  Geol.  Survey,  Vol.  IX,  1899,  pji.  .Sr.O-KT. 


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CHANGES  OF  DEAINAGE  IN  SOUTHWESTERN  INDIANA.  97 

along  the  present  Mississippi  bluffs  is  a  few  feet  lower  than  the  bed  of  the 
abandoned  channel.  This  lower. altitude  along  the  Mississippi  is  due  to  the 
incomplete  filling  of  the  preglacial  channel  by  drift. 

CHANGES    OF    DRAINAGE    IN    SOUTHWESTERN    INDIANA. 

The  lUinoian  invasion  produced  important  drainage  modifications  in 
southwestern  Indiana,  only  a  part  of  which  have  as  yet  been  fully  worked 
out.  The  present  discussion  aims  to  deal  chiefly  with  the  changes  which 
have  received  the  most  careful  attention.  The  discussion  begins  with 
streams  in  the  southwest  corner  of  Indiana. 

By  reference  to  the  map,  PL  VIII,  it  will  be  seen  that  the  greater  part 
of  Posey  County  and  adjacent  portions  of  Vanderburg  and  Gibson  counties 
are  now  drained  westward  into  the  Wabash  through  Big  Creek.  The 
South  Fork  leads  almost  du'ectly  west  from  near  Evansville  in  Vanderburg 
County  to  its  junction  with  the  North  Fork  in  central  Posey  County.  The 
North  Fork  leads  northwest  from  northern  Vanderburg  across  southwestern 
Gibson  into  Posey  County,  and  there  near  the  village  of  Cynthiana  turns 
southwestward  and  maintains  this  course  to  the  Wabash.  It  receives  a 
tributary  from  the  southeast  near  the  crossing  of  the  Peoria,  Decatur  and 
Evansville  Railway,  but  no  other  tributary  of  importance  enters  above  its 
junction  with  the  East  Fork.  An  examination  of  the  head-water  portion  of 
the  North  Fork  has  brought  to  light  decisive  evidence  that  its  preglacial 
line  of  discharge  was  westward  into  Black  River  and  thence  to  the  Wabash 
at  a  point  20  miles  or  more  above  the  present  mouth  of  the  creek.  A 
broad  valley  deeply  filled  with  di-ift  leads  from  Big  Creek  westward  to 
Black  River,  passing  just  north  of  the  village  of  Cynthiana.  The  aban- 
doned valley  is  nearly  a  mile  in  width,  while  the  new  passage  is  scarcely 
one-tenth  of  a  mile  in  width.  The  creek  soon  enters  another  old  valley 
whose  head  water  portion  is  occupied  by  the  southeastern  tributary  referred 
to  above,  but  whose  lower  course  is  abandoned.  The  Peoria,  Decatur  and 
Evansville  Railway  utilizes  the  abandoned  valley  between  Big  Creek  and 
Poseyville.  From  Poseyville  the  valley  passes  northwest  to  Black  River. 
In  the  narrow  valley  near  Cynthiana  the  present  stream  thus  cuts  across  a 
low  ridge  separating  two  streams,  which  formerly  drained  northwestward 
into  Black  River.     Below  the  railway  crossing  Big  Creek  soon  enters  a 

MON  XXXVIII 7 


98  THE  ILLINOIS  GLACIAL  LOBE. 

narrow  valley  and  crosses  the  preglacial  divide  between  Black  River  and  tlie 
Sonth  Fork  of  Big-  Creek.  Thus  the  latter  di-amage  basin  has  been  greatly 
enlarged  at  the  expense  of  the  former.  The  glacial  boundary  follows 
nearly  the  present  course  of  the  North  Fork  of  Big  Creek  below  Cynthiana, 
and  the  location  of  the  new  stream  across  the  rock  point  near  that  village 
is  e\adently  due  to  the  presence  of  the  ice  sheet  in  the  lowlands  to  the  west, 
and  the  diversion  across  the  divide  between  the  preglacial  drainage  basins 
of  Black  River  and  Big  Creek  is  due  to  occupancy  of  the  former  by  the 
ice  sheet. 

The  Pigeon  Creek  di-ainage  basin  has  also  been  enlarged  at  the 
expense  of  Black  River.  Muddy  Fork  of  Pigeon  Creek  lies  in  a  lowland 
which  connects  on  the  southwest  with  Black  River,  and  this  lowland  appar- 
ently received  the  portion  of  the  Pigeon  Creek  drainage  in  Gibson  and 
northern  Warrick  counties.  The  location  of  the  col  was  not  definitely 
worked  out,  though  it  is  in  all  probability  east  of  Elberfeld,  in  T.  4  S., 
R.  9  W.  Upon  referring  the  question  of  changes  of  drainage  in  the  Pigeon 
Creek  basin  to  Dr.  George  H.  Ashley,  of  the  Indiana  survey,  who  has 
made  an  examination  of  the  portion  in  Warrick  County  ouiside  the  limits 
of  the  writer's  own  examinations,  the  following  reply  was  received:^ 

I  think  you  are  right  in  believing  that  the  head  waters  of  Pigeon  Creek  drained 
to  the  west  in  preglacial  times,  the  divide  running  nearly  east  and  west  across  the 
center  of  T.  4  S.  through  Es.  8,  9,  and  10  W.  The  present  course  of  Pigeon  Creek 
through  Ts.  4  and  5  S.,  E.  9  W.,  while  not  so  markedly  a  postglacial  channel  as  many 
to  be  found,  has  nevertheless  several  of  the  characters  of  such  a  channel.  In  the 
tirst  place  the  bottoms  are  narrow,  averaging  probably  less  than  one-half  mile  in 
width  from  above  Elberfeld  to  below  Millersburg,  or  scarcely  half  the  usual  width  of 
the  west-flowing  head  water  portion.  Secondly,  the  blufl's  are  more  abrupt  than  is 
usual  for  streams  of  this  size  in  -that  region.  This  is  especially  true  north  of  east 
from  Elberfeld,  where  the  stream  appears  to  have  crossed  an  old  divide.  Thirdly, 
the  short  tributaries  on  each  side  of  the  streams  in  the  vicinity  of  the  supposed 
divide  also  sustain  this  view.  Fourthly,  reports  suggest  that  rock  is  to  be  found 
within  a  dozen  feet  below  the  stream  bed  in  this  narrow  portion,  but  this  has  not  as 
yet  been  verified. 

The  changes  of  drainage  become  still  more  important  in  passing  north- 
eastward into  Pike  and  Dubois  counties.  The  streams  which  fornaerly  had 
a  northwestward  discharge  into  the  White  River  drainage  have  been  turned 
westward  just  outside  the  glacial  boundary  to  form  the  Patoka  River,  as 


'  Letter  written  June  8,  1898. 


CHANGES  OF  DEAINAGE  IN  SOUTHWESTERN  INDIANA.  99 

may  be  seen  by  reference  to  the  map,  PI.  VIII.  These  perhaps  may  be 
discussed  to  best  advantage  by  beginning  at  the  east  with  the  head  waters 
of  the  Patoka. 

The  portion  of  the  Patoka  above  Jasper  seems  to  be  following  a 
preglacial  line,  but  at  that  town  a  deflection  of  the  stream  into  another 
drainage  basin  has  been  effected.  The  preglacial  valley  is  easily  traced 
from  the  Patoka,  in  sec.  24,  T.  1  S.,  R.  5  AV.,  northwestward  to  Mill  Creek 
Valley  and  thence  into  East  White  River.  Its  breadth  is  about  IJ  miles, 
and  it  has  been  filled  with  sand  and  loess-like  silt  to  a  height  of  30  to  35 
feet  above  the  present  level  of  Patoka  River,  in  sec.  24,  or  to  about  490. 
feet  above  tide.  This  filling  was  sufficient  to  turn  the  stream  across  a  low 
divide  in  the  east  part  of  Jasper.  In  opening  a  passage  across  this  divide 
the  stream  has  accomplished  a  remarkably  small  amount  of  work.  The 
naiTOw  part  of  the  valley  which  marks  the  position  of  the  old  divide  is  only 
about  one-half  mile  in  length,  600  to  800  feet  in  width,  and  20  to  35  feet 
in  depth.  The  stream  is  reported  to  be  several  feet  in  depth  through  this 
narrow  portion,  thus  increasing  the  depth  of  erosion  perhaps  10  feet.  There 
is  in  part  of  the  gorge  a  thick-bedded  sandstone  which  has  probabl)-  greatly 
resisted  lateral  erosion. 

Immediately  south  of  Jasper  the  present  Patoka  River  enters  a  valley 
fully  1  mile  in  width  which  constitutes  the  preglacial  line  of  discharge  for 
several  southern  tributaries  entering  in  Dubois  County.  The  valley  is  not 
occupied  far  by  the  present  stream,  but  leads  from  Jasper  in  a  course  north  of 
west  into  Pike  County,  passing  south  of  Ireland  and  directly  imder  the  vil- 
lage of  Otwell,  its  course  for  several  miles  being  nearly  coincident  with  Flat 
Creek,  though  in  the  reverse  direction.  Whether  it  joined  the  East  White 
Valley  near  Highbanks  or  entered  a  few  miles  below,  at  the  mouth  of  Mud, 
Creek,  is  undetermined.  There  are  shallow  valley-like  depressions  connect- 
ing the  abandoned  valley  with  East  White  River  along  each  course  which 
are  underlain  by  heavy  deposits  of  drift,  each  of  which  apparently  has  a 
width  sufficient  to  have  accommodated  the  old  stream.  Probably,  however, 
one  of  these  lines  will  be  found  to  be  separated  from  the  old  valley  by  a 
concealed  rock  barrier.  This  old  valley,  as  above  noted,  has  a  rock  floor 
considerably  below  the  present  bed  of  the  neighboring  portion  of  East 
White  River,  a  boring  at  Otwell  having  failed  to  reach  rock  at  a  level  about 
35  feet  below  the  river. 


100  THE  ILLINOIS  GLACIAL  LOBE. 

The  present  Patoka  Kiver  leads  southward  from  Jasper  for  several 
miles,  occupying  the  northern  end  of  the  broad  valley  of  Hunleys  Creek, 
a  southern  tributary  of  the  abandoned  valley  just  discussed.  The  river  then 
takes  a  northwestward  course,  cutting-  across  a  narrow  neck  of  upland  and 
touching-  the  border  of  the  abandoned  valley  about  2  miles  south  of  Ireland. 
In  this  passage  across  the  neck  of  upland  the  width  of  the  flood  plain  is 
nowhere  less  than  one-fourth  of  a  mile,  or  about  double  the  width  of  the 
valley  bottom  in  the  gorge  at  Jasper.  Whether  this  difference  iia  size  is 
referable  to  variations  in  the  texture  of  the  rock  or  is  due  to  difference  in 
date  of  deflection  has  not  been  determined.  It  seems,  however,  not  improb- 
able that  this  narrow  neck  had  been  encroached  upon  by  valleys  on  each 
side  and  severed  from  the  main  upland  prior  to  the  glacial  invasion. 

After  touching  the  old  valley  near  Ireland,  the  Patoka  turns  to  the 
southwest  and  near  the  line  of  Dubois  and  Pike  counties  enters  a  narrow 
valley  800  to  1,000  feet  in  width.  The  narrow  portion  extends  from  the 
county  line  southwest  about  2  miles  to  the  mouth  of  Rocky  Creek,  a  south- 
ern tributary.  It  there  expands  to  twice  or  three  times  the  Avidth  of  tlie 
narrow  portion  and  from  that  point  gradually  increases  in  width  down  the 
stream,  reaching  nearly  2  miles  in  western  Pike  County.  The  narrow  por- 
tion evidently  marks  the  position  of  a  preglacial  divide.  That  this  divide 
had  been  reduced  to  a  low  elevation  is  shown  by  neighboring  cols,  which, 
though  low,  were  not  utilized  by  this  stream  in  selecting  a  new  com'se.  One 
of  these  cols  at  the  village  of  Velpen  stands  only  510  feet  above  tide.  It 
is  probable  that  the  blockaded  stream  had  to  rise  no  higher  than  500  feet  to 
cross  the  divide,  or  to  a  height  of  less  than  75  feet  above  its  present  level; 
possibly  the  divide  was  not  more  than  475  feet  at  the  col.  The  latter  alti- 
tude is  slightly  lower  than  the  sand  and  silt  filling  made  by  Lake  Patoka 
which,  as  above  noted,  is  found  in  the  abandoned  valleys  to  the  north  and 
east  of  this  divide.  This  filling  is  conspicuous  in  the  vicinity  of  the  divide 
as  well  as  above,  and  seems  to  pass  down  the  present  stream  beyond  the 
divide  without  appreciable  decrease  in  altitude.  The  col  was  nearly  if  not 
quite  covered  by  silt  before  the  present  channel  was  opened  across  it. 

The  Patoka  River  apparently  follows  the  line  of  a  preglacial  stream 
from  tlie  mouth  of  Rocky  Creek,  in  eastern  Pike  County,  westward  iiito 
Gibson  County  to  the  bend  about  6  miles  above  Patoka.  It  there  is  in  a 
low  tract  which  extends  northward  to  White  River.     But  instead  of  follow- 


CHANGES  OF  DRAINAGE  IN  SOUTHWESTERN  INDIANA.        101 

ing'  this  lowland  it  continues  westward  and  passes  through  a  range  of  hills 
which  leads  northward  from  Princeton  past  Patoka  to  White  River  at  Hazel- 
ton.  This  deflection  lies  within  the  glaciated  region  and  calls  for  a  some- 
what different  explanation  from  those  just  considered.  It  is  probable  that 
a  lower  passage  was  afforded  across  a  col  near  Patoka  than  the  lowland  to 
the  north  else  the  stream  would  not  have  suffered  this  deflection.  In  the  pas- 
sage through  this  range  of  hills  at  Patoka  the  A^alley  is  reduced  to  a  width 
of  scarcely  one-half  mile  or  to  about  one-fourth  the  width  of  the  preglacial 
valley  which  it  occupies  a  few  miles  to  the  east.  Upon  passing  this  range 
the  stream  soon  enters  the  broad  valley  of  the  Wabash  and  takes  a  some- 
■\vhat  direct  course  into  that  river. 

Since  Patoka  Eiver  enters  the  glaciated  region  in  its  lower  course  the 
question  arises  whether  it  found  discharge  beneath  the  ice  margin  during 
the  time  when  its  lower  coiu'se  was  covered  by  the  ice  sheet  or  found  a  line 
or  lines  of  discharge  southward  through  the  unglaciated  region  into  the  Ohio. 
There  is  a  col  on  the  divide  between  Patoka  and  Ohio  rivers  crossed  by  the 
abandoned  Wabash  and  Ohio  Canal  about  1  mile  southwest  of  Francisco, 
which  stands  only  480  feet  above  tide,  or  about  the  altitude  of  the  silt 
deposits  along  the  Patoka  in  western  Dubois  and  Pike  counties.  From  this 
col  there  is  an  open  line  into  the  head  waters  of  Pigeon  Creek.  But  as 
noted  above  there  may  have  been  another  col  in  northern  Warrick  County 
on  the  present  line  of  Pigeon  Creel?:  to  offer  resistance  to  the  discharge  of 
water  to  the  Ohio.  It  is  doubtful,  however,  if  that  col  stood  any  higher 
than  the  one  near  Francisco,  and  it  may  have  been  so  low  as  to  afford  an 
eas}'  passage  for  the  stream.  An  examination  of  the  col  near  Francisco 
failed  to  bring  to  light  decisive  evidence  that  a  stream  had  crossed  it.  The 
sag  crossing  the  divide  is  scarcely  100  rods  in  width  and  is  not  bordered  by 
banks  or  well-defined  erosion  contours.  The  features  seem  to  be  no  differ- 
ent from  those  of  other  sags  at  higher  altitudes  on  the  divide.  The  canal 
cuts  through  about  12  feet  of  loesslike  yellowish-brown  earth  before  strik- 
ing the  rock  surface,  which  is  similar  to  the  material  found  on  border  dis- 
tricts at  all  altitudes.  It  seems  less  probable  that  cols  on  the  Patoka-Ohio 
divide  farther  east  were  utilized,  for  they  stand  considerably  higher  than 
the  col  under  consideration;  the  lowest  stand  probably  about  525  to  550 
feet  above  tide.  The  col  crossed  by  the  railway  near  Ferdinand  station,  7 
miles  south  of  Huintingburg,  is  probably  as  low  as  any,  standing  530  feet 


102  THE  ILLINOIS  GLACIAL  LOBE. 

above  tide.  The  sag  leading  across  this  divide,  hke  that  near  Francisco,  is 
too  narrow  to  have  suflPered  much  erosion  l)y  a  stream  discharging  across  it. 
On  the  whole  the  evidence  of  southward  discharge  into  the  Ohio  seems  very 
weak,  and  the  view  that  the  water  which  accumulated  along  the  ice  margin  in 
Dubois  and  Pike  counties  found  its  main  discharge  to  the  Wabash  under  the 
ice  margin,  appears  more  probable.  At  most  the  col  near  Francisco  appears 
to  have  served  only  temporarily  as  a  waste  weir  for  the  accumulated  waters. 

Several  interesting  deflections  of  small  streams  have  been  noted  in  the 
vicinity  of  the  glacial  boundary  in  the  district  lying  between  East  White 
and  the  main  White  River.  These  have  been  brought  to  light  by  the 
studies  of  Mr.  C.  E.  Siebenthal,  of  the  Indiana  geological  survey,  with 
perhaps  one  exception,  that  of  Furse  Creek  in  northwestern  Martin  County. 
Siebenthal  has  kindly  furnished  notes  on  these  changes  of  drainage  in 
advance  of  the  pidolication  of  his  report.  Since  receiving  his  notes  the 
writer  has  had  opportunity  to  examine  some  of  the  deflections  brought 
to  light  by  Siebenthal,  but  for  the  detailed  examination,  as  well  as  the 
discovery  of  these  deflections,  Siebenthal  should  receive  credit.  It  is 
scarcely  probable  that  all  the  deflections  have  been  brought  to  light,  for  the 
valle5's  of  some  streams  in  Daviess  County  have  not  been  given  sufficient 
attention  to  wan-ant  their  discussion.  The  first  deflection  discussed  is  that 
of  Furse  Creek,  after  which  the  streams  examined  by  Siebenthal  are  taken 
up  in  order  from  south  to  north. 

Furse  Creek  as  shown  in  PI.  IX,  strikes  the  glacial  boundary  about  2 
miles  east  from  the  west  line  of  Martin  County.  It  there  turns  abruptly 
southward  and  enters  a  gorge  in  the  southeast  part  of  sec.  8,  T.  5  N.,  R.  4 
W.,  in  which  the  creek  bluflPs  border  the  stream  closely  on  each  side  for  a 
mile  or  more.  The  stream  then  enters  an  open  valley  formed  by  the  small 
southern  tributary  which  joins  it  in  sec.  18.  Whether  it  has  suft'ered  other 
deflections  below  this  point  has  not  been  determined.  From  the  point  of 
deflection  in  sec.  8  a  lowland  tract  heavily  coated  \\'ith  drift  leads  north- 
.  westward  to  the  valley  of  Doans  Creek,  near  Scotland.  This  probably  was 
the  preglacial  line  of  discharge  for  Furse  Creek. 

Siebenthal  has  found  that  Richland  Creek  was  deflected  southward 
near  the  point  where  it  strikes  the  glacial  boundary  li  miles  east  of  the 
village  of  Newark,  its  old  course  ha\'ing  been  northwestward  from  that 
point.  The  position  of  the  col  on  the  old  divide  below  the  point  of  deflec- 
tion of  the  creek  is  clearly  shown  in  a  view  from  a  hill  southeast  of  Newark. 


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CHANGES  OF  DRAINAGE  IN  SOUTHWESTEKN  INDIANA.        103 

The  bluffs  close  in  on  either  side  of  the  creek  near  the  center  of  sec.  19, 
sloping  gradually  to  the  border  of  the  stream.     The  stream  has  cut  a  notch 
nearly  100  feet  in  depth  across  the  col.     It  soon  enters  a  small  preglacial 
valley,  but  appears  to  follow  the  course  of  that  valley  for  only  a  short  dis- 
tance.    Its  course  for  about  8  miles  is  mainly  across  rock  points  and  low 
divides  and  lies  just  outside  the  glacial  boundary.     At  its  junction  with 
Beech  Creek  a  preglacial  valley  is  found,  but  tlie  stream  turns  out  of  this 
valley  in  sec.  9,  T.  7,  R.  4  W.,  and  takes  a  direct  course  westward  through 
a  gorge,  thus  cutting  off  a  rock  point  on  the  south  side  of  the  preglacial 
Beech  Creek  Valley.     It  reenters  the  old  valley  near  the  corners  of  sees. 
7,  8,   17,    and  18,   after  traversing  a  gorge   for   about  IJ  miles,    and  is 
reported  by  Siebenthal  to  continue  in  a  preglacial  valley  to  its  mouth. 
The  stream  lies  within  the  glaciated  region  throughou.t  the  portion  below 
the  mouth  of  Beech  Creek,  but  is  only  about  5  miles  by  direct  line  inside 
the  glacial  boundary  at  its  entrance  into  White  River.     It  seems  probable 
that  the  stream  discharged  through  the  low  glaciated  districts  bordering 
White  River,  even  at  the  maximum  extension  of  the  ice,  for  no  line  of  dis- 
charge is  found  across  the  elevated  districts  outside  the  glacial  boundary: 
In  the  head-water  portion  of  Richland  Creek,  above  the  point  of  deflec- 
tion from  its  preglacial  valley,  there  appears  to  have  been  a  glacial  lake  for 
which  Siebenthal  has  proposed  the  name  Lake  Richland.     The  presence 
of  the  lake  is  shown  by  terraces  and  deposits  of  silt  and  sand  which  filled 
'  the  valley  up  to  a  definite  level.     They  stand  nearly  100  feet  above  the 
creek  at  the  point  of  deflection,  but  in  passing  up  the  valley  they  gradually 
approach  the  creek  level,  being  but  30  or  40  feet  above  the  stream  in  the 
vicinity  of  Whitehall.     Whether  they  are  perfectly  horizontal  has  not  been 
determined.     The  lake  apparently  extended  up  the  creek  a  short  distance 
into  Monroe  County. 

About  4  miles  south  from  the  point  where  Richland  Creek  turns  west- 
ward into  the  glaciated  district  the  glacial  boundary  comes  to  the  west  end 
of  another  glacial  lake  whose  site  is  now  known  as  the  "American  bottom." 
It  extends  eastward  about  5  miles  from  the  glacial  boundary  and  has  an 
average  width  of  nearly  1  mile.  This  old  lake  bottom  now  has  subterra- 
nean di-ainage  southwestward  through  sand  deposits  to  a  tributary  of  Clifty 
Creek,  where  it  appears  in  the  form  of  springs.  Because  of  the  subterranean 
drainage  the  plain  is  preserved  in  nearly  the  condition  left  by  the  lake. 


104  THE  ILLINOIS  GLACIAL  LOBE. 

Passing  uortln\'ard  iuto  Owen  County  there  is  found  a  slight  detlection 
in  Raccoon  Creek,  just  inside  the  glacial  boundary.  Instead  of  following 
its  old  course  the  creek  glasses  across  a  rock  point  on  the  south,  occupying 
a  gorge  for  about  a  mile.  The  head-water  tributaries  of  Raccoon  Creek 
outside  the  glacial  boundary  caiTy  terraces  of  silt  and  sand  which  are  inter- 
preted by  Siebenthal  to  be  the  accumulations  made  in  small  glacial  lakes 
held  in  front  of  the  ice  sheet. 

The  "Flat  Woods"  of  eastern  Owen  and  western  Monroe  counties 
cover  an  area  of  several  square  miles  of  elevated  land,  immediately  inside 
the  glacial  boundary.  The  flats  in  this  area  are  interrupted  by  hilly  tracts, 
and  the  entire  area  is  above  the  general  level  of  border  tracts.  These 
features  are  thought  to  indicate  that  no  large  stream  occupied  the  "Flat 
Woods"  in  preglacial  times.  It  is  suggested  by  Siebenthal  that  the  region 
had  a  system  of  subterranean  drainage  prior  to  the  glacial  invasion,  but 
that  glacial  accumulations  have  caused  a  change  to  surface  drainage.^  The 
flats  are  now  di-ained  chiefly  to  the  north  through  McCormack's  Creek. 
The  western  portion  drains  westward  through  Ellison's  Branch  into  White 
River.  On  McCormack's  Creek  there  is  a  fall  about  a  mile  from  its  mouth, 
above  which  there  is  only  a  shallow,  poorly  drained  valley.  The  main 
work  of  the  stream  since  the  Grlacial  period  has  been  given  to  the  exca^-a- 
tion  of  the  gorge  below  the  fall,  but  no  accurate  estimate  was  made  of  the 
work  accomplished  in  cutting  back  to  the  fall. 

The  eff"ect  of  the  ice  invasion  upon  the  course  of  White  River  has  been 
even  greater  than  on  the  small  eastern  tributaries  which  enter  it  from  the 
unglaciated  region.  The  preglacial  drainage  is  so  greatly  concealed  above 
the  north  line  of  Greene  County  tlaat  it  seems  impracticable  to  determine 
even  the  course  of  the  main  drainage  line.  The  stream  is  now  occupying  a 
preglacial  valle}'  for  a  few  miles  in  southwestern  Morgan  County,  and  is 
also  in  a  preglacial  valley  throughout  much  of  its  course  below  Owen 
County.  But  in  its  passage  across  Owen  County  it  is  opening  a  new  val- 
ley. It  has  been  suggested  that  this  stream  had  a  subterranean  passage 
across  the  sink-hole  region  of  Owen  County,  in  which  case  no  well-defined 
suiiace  channel  may  have  been  opened  prior  to  the  glacial  invasion.  The 
available  data  sociii  insulHcicnt  to  t(^st  the  applioabilitv  of  this  interpretation. 


'Tweuty-first  Aun.  Rept.  ludiana  Geol.  Survey,  1896,  pp.  301, 302. 


EELATIOKS  OF  THE  ILLINOIAN  DRIFT  SHEET.  105 

PLEISTOCENE  DEPOSITS  BEISHEATH  THE  lELI^TOIA^T  TILL  SHEET. 

Although  the  Illinoian  till  sheet  throughout  much  of  the  region  under 
discussion  may  rest  immediately  on  the  rock,  there  are,  in  places,  deposits 
separating  it  from  the  rock  formations.  The  deposits  are  principally  of  two 
classes — namely,  the  Kansan  till,  Avith  perhaps  a  somewhat  distinct  pre- 
Illinoian  till,  and  vallej''  silts  or  sands. 

KANSAN  TILL. 

Attention  has  been  called  to  the  till  of  southeastern  Iowa  and  western 
Illinois,  which  underlies  the  Illinoian  drift  and  which  is  referred  to  the 
Kansan.  The  full  extent  of  this  sheet  of  till  in  western  Illinois  is  not 
determined.  Its  eastern  border  comes  to  the  Mississippi  Valley  from  the 
south  near  Hannibal,  Missouri,  and  it  probably  continues  northward  into 
Illinois  across  Adams  and  Hancock  counties.  It  probably  also  extends  into 
counties  east  of  the  Mississippi  farther  north,  although  this  has  not  been  so 
clearly  determined.  That  it  extended  into  western  Adams  and  Hancock 
counties  is  shown  by  at  least  two  lines  of  evidence.  The  first  line  of 
eAddence  is  that  furnished  by  striation.  An  exposure  of  a  striated  ledge 
with  a  bearing  S.  65°  E.  appears  on  the  south  side  of  Wagner's  Creek,  about 
4  miles  above  Hamilton,  Illinois,  and  2  miles  east  of  the  Mississippi.  This, 
so  far  as  known,  is  the  only  instance  yet  discovered  of  striation  produced 
by  the  Keewatin  ice  field  east  of  the  Mississippi  and  south  of  the  Wisconsin 
Driftless  Area.  The  striae  reported  above  in  the  vicinity  of  Burling-ton, 
Iowa,  are  in  some  cases  situated  on  the  brow  of  the  west  bluff  of  the 
Mississippi,  showing  that  the  eastward  movement  extended  at  least  to  the 
Mississippi  Valley. 

The  second  line  of  evidence  of  the  extension  of  the  Keewatin  ice  sheet 
into  western  Illinois  is  furnished  by  till  deposits  separated  from  the  over- 
lying Illinoian  by  a  soil  and  carrying  other  evidences  of  greater  age  than 
the  Illinoian.  In  the  discussion  of  the  border  of  the  Illinoian  di'ift  in  Han- 
cock and  Adams  counties,  Illinois,  attention  was  called  to  the  occm-rence  of 
a  heavy  sheet  of  blue  till  similar  in  structure  to  that  found  beneath  the 
Illinoian  west  of  the  Mississippi,  and  to  a  few  exposures  near  the  line  of 
Hancock  and  Adams  counties  of  a  black  soil  separating  the  till  from  the 
overlying  Illinoian.     In  these  exposures  it  was  found  that  the  till  under  the 


106  THE  ILLINOIS  GLACIAL  LOBE. 

soil  had  been  leached  to  a  depth  of  several  feet,  a  feature  which  testifies  to 
the  lapse  of  a  considerable  period  between  the  deposition  of  the  two  till 
sheets.  This  black  soil  between  the  tills  is  also  penetrated  in  wells  in 
western  Hancock  County. 

A  possible  third  line  of  evidence  of  the  extension  of  the  Keewatin  ice 
sheet  into  western  Illinois  is  found  in  the  presence  of  laminated  clays  in  a 
buried  preglacial  valley  in  central  Adams  County.  These  clays  ai"e  con- 
jectured to  be  due  to  an  obstruction  of  the  lower  course  of  the  valley  in 
western  Adams  County  by  the  Keewatin  ice  sheet.  The  obstruction  might 
have  formed  a  lake  in  which  these  deposits  were  laid  down  contempora- 
neously with  Kansan  till. 

The  lapse  of  a  long  interval  between  the  deposition  of  the  Kansan  till 
and  the  Illinoian  is  clearly  shown  in  southeastern  Iowa,  not  only  by  the 
presence  of  a  soil  and  leached  subsoil  between  two  sheets,  but  by  the 
markedly  greater  erosion  of  the  Kansan  than  of  the  Illinoian  sheet.  This 
erosion  is  manifest  to  the  trained  observer  on  passing  from  one  sheet  to 
the  other.  In  the  district  occupied  by  the  Kansan  the  erosion  is  so  great 
that  only  narrow  remnants  of  the  original  diift  plain  are  preserved  along 
the  water  partings.  But  in  the  district  occupied  by  the  Illinoian  more  than 
half  the  original  drift  plain  is  preserved,  and  that,  too,  on  the  immediate 
borders  of  the  Mississippi,  where  conditions  for  erosion  are  more  favorable 
tlian  in  the  area  to  the  west  which  is  occupied  by  the  eroded  Kansan  sheet. 
The  great  contrast  in  amount  of  erosion  supports  strongly  the  view  that  a 
longer  interval  elapsed  between  the  Kansan  and  lUinoian  glaciations  than 
between  the  Illinoian  and  the  present  time. 

Attention  is  called,  in  the  discussion  of  the  Illinoian  drift  border,  to  an 
instance  of  its  filling  a  valley  in  Des  Moines  County,  Iowa,  that  had  been 
cut  in  the  Kansan  drift.  This  valley  apparently  had  a  depth  of  50  feet 
beh.»w  the  bordering  plains,  but  no  data  are  available  concerning  its  width. 
It  appears  fi-om  a  study  of  the  ten-aces  on  valleys  cut  in  the  Kansan  drift 
of  southeastern  Iowa,  that  the  erosion  in  the  interval  between  the  Kansan 
and  Illinoian  stages  of  glaciation  was  such  as  to  form  broad  shallow  vallej's 
rather  than  nan-ow  deep  ones.  The  large  valleys  appear  to  have  been  cut 
to  a  depth  of  but  oO  or  60  feet,  though  they  had  a  width  of  one  or  two 
miles. 


PLEISTOCENE  DEPOSITS  BENEATH  TILL  SHEET.  107 

PRE-ILLINOIAN  (?)  TILL  AND  ASSOCIATED  DEPOSITS. 

As  yet  the  evidence  pointing  toward  the  occurrence  of  drift  of  greater 
age  than  the  IlHnoian  in  the  districts  to  the  east,  which  lie  beyond  the  hniits 
of  the  Keewatin  ice*  sheet,  has  not  sufficient  strength  to  make  it  seem 
advisable  to  advocate  a  pre-Illinoian  till.  There  are  occasional  well  sections 
reported  to  have  passed  through  a  bed  of  wood  or  of  soil  in  the  midst  of 
the  till  in  central  Illinois.  Thus  at  Pana  a  section  reported  by  Worthen  is 
as  follows:^ 

Section  of  well  at  Pana,  Illinois. 

Feet. 

Soil  and  clay 11 

Blue  clay 4 

Sand  and  gravel 12 

Hard  red  clay 18 

Forest  bed 3| 

Blue  clay : 57 

Black  soil  or  forest  bed 2| 

Blue  clay 19 

Total 127 

This  section  is  based  upon  specimens  preserved  from  a  test  boring  with 
diamond  drill.  The  specimens  were  recently  examined  by  the  writer  and 
some  light  obtained  concerning  the  interpretation  to  be  put  upon  this  sec- 
tion. The  upper  15  feet  consists  of  a  pebbleless  material  to  be  classified 
with  the  loess.  The  upper  forest  bed  proves  to  be  simply  fragments  of 
wood  embedded  in  ordinary  till.  The  till  was  found  to  be  very  calcareous 
at  the  horizon  of  this  wood  and  to  show  no  evidence  of  atmospheric  expo- 
sure subsequent  to  its  deposition.  The  wood  appears,  therefore,  to  be 
simply  material  deposited  in  the  till  by  the  ice  sheet  and  has  no  more  si^-nifi- 
cance  in  determining  a  time  interval  than  the  presence  of  a  Paleozoic  fossil 
embedded  in  the  drift.  The  lower  forest  bed  consists  of  a  humus-stained 
clay  in  which  fragments  of  wood  occur;  it  is  apparently  a  soil.  Under 
it  is  a  greenish  clay  subsoil,  such  as  occurs  beneath  swamps.  This,  as 
well  as  the  soil,  is  pebbleless.  At  the  bottom  of  the  clay,  resting  on  the 
limestone  rock,  there  is  a  thin  bed  of  ferruginous  conglomerate,  in  which 
angular  chert  is  mingled  with  waterworn  pebbles.  No  Canadian  rocks  or 
specimens  which  can  be  referred  to  glacial  action  were  found.  This  raises 
the  question  whether  the  conglomerate  is  not  of  preglacial  age.     The  soil 

1  Geol.  Illinois,  Vol.  VII,  pp.  22-23;  also  Vol.  VIII,  p.  15. 


108  THE  ILLINOIS  GLACIAL  LOBE. 

at  the  base  of  the  drift,  together  with  the  underlying  subsoil,  appears  to  be 
connected  but  remotely  at  least  with  glacial  agencies.  The  de230sit  appar- 
ently antedated  the  deposition  of  the  overlying  till  by  a  considerable 
interval.  The  writer  is  inclined  to  refer  to  the  Illinoian  invasion  the  series 
of  clays  setting  in  at  27  feet  and  extending-  to  106  feet. 

Worthen  reports  a  section  at  Virginia,  Illinois,  in  which  a  black  soil 
appears  between  tills  at  a  depth  of  67  to  70  feet.'  On  making  inquiry  of 
Dr.  J.  F.  Snj-der,  of  Virginia,  concerning  this  section,  it  is  found  that  the 
recoi'd  of  the  coal  shaft  on  which  Worthen  based  his  section  of  the  di-ift 
was  not  kept  with  a  sufficient  degree  of  accuracy  to  insure  its  correctness. 
Dr.  Snyder  is  of  opinion  that  the  distance  to  rock  is  about  70  feet  greater 
than  shown  by  this  record.  It  would  certainly  be  hazardous  to  base  an 
important  time  interval  on  the  reported  occurrence  of  soil  in  the  shaft  at 
Virginia. 

The  section  of  a  coal  shaft  at  Bloomington  reported  by  Dr.  H.  M. 
Banister^  represents  the  occurrence  of  two  buried  soils.  The  section  as 
reported  by  Dr.  Banister  is  as  follows : 

Section  of  coal  shaft  at  Bloomington,  Illinois. 

Veet. 

Surface  soil  and  Ijrown  clay 10 

Blue  clay 40 

Gravelly  hard  pan 60 

Black  mold  with  pieces  of  wood 13 

Hardpan  and  clay 89 

Black  mold,  etc 6 

Blue  clay 34 

Quicksand,  buifaud  drab  in  color,  and  containing-  fossil  shells 2 

Total  drift 254 

In  this  section  the  upper  11 U  feet  may  be  referred  with  considerable 
confidence  to  the  Wisconsin  drift.  The  upper  "black  mold"  at  110  to 
123  feet  was  apparently  post-lllinoian.  It  is  probable  that  the  Illinoian 
sheet  is  represented  in  the  "liardpan  and  cla}-"  at  123  to  212  feet.  The 
remainder  of  the  section  would  be  therefore  pre-IUinoian.  Whether  the 
blue  clay  Ijelow  tlie  lower  "black  mold"  is  a  glacial  deposit  is  not  clearly 
shown.  It  ma}-  pnn-e  to  be  a  water  deposit.  In  view  of  this  uncertainty 
it  seems  unsafe  to  use  this  section  as  evidence  for  the  occurrence  of  a  pre- 
IlliiKiiaii  (h-ift  slieet  in  central  Illinois. 

'  Op.  cit.,  Vol.  Vm,  p.  16.  ■'  Op.  cit.,  Vol.  IV,  1870,  p.  178.    Also  Vol.  VIII,  p.  14. 


PEE-ILLINOIAN  (?)  TILL  AND  ASSOCIATED  DEPOSITS.  109 

lu  this  connection  attention  is  called  again  to  the  section  of  a  shaft  at 
Coatsburg,  in  Adams  County,  in  which  a  laminated  clay  of  considerable 
depth  underlies  the  till,  but  which  is  not  a  strictly  glacial  deposit.  The 
Bloomington  section  may  be  of  similar  character  in  its  lower  portion. 
The  sections  above  discussed  comjjrise  the  most  puzzling  ones  reported  in 
the  geology  of  Illinois.  The  buried  soils  there  reported  are  usually  found, 
when  in  the  district  outside  the  Wisconsin  drift,  either  at  the  base  of  the 
loess,  which  is  a  post-Tllinoian  interval  (Sangamon),  or  at  the  bottom  of 
the  glacial  deposits,  where  only  silt  or  sand  occurs  between  the  soil  and  the 
underlying  rock. 

Prof.  R.  D.  Salisbury  has  reported  the  occurrence  of  two  sheets  of 
drift  in  southeastern  Illmois  and  southwestern  Indiana.  He  considers  them 
representatives  of  two  episodes  of  a  single  glacial  epoch.  The  upper  sheet 
is  thought  to  extend  fully  as  far  as  the  lower,  if  not  beyond  it.^  As  the 
features  referred  to  by  Salisbury  have  never  been  investigated  by  the 
writer,  some  hesitancy  is  felt  in  offering  an  interpretation.  It  is,  however, 
suggested  that  the  invasion  limited  on  the  southwest  by  the  ridged  drift  of 
the  Kaskaskia  Basin  may  have  formed  the  upper  sheet,  while  the  invasion, 
which  in  southwestern  Illinois  was  the  more  extensive  one,  may  have  formed 
the  lower  sheet.  Possibly  the  interval  will  prove  to  be  too  long  to  supjDort 
this  interpretation.  In  that  case  the  lower  sheet  would  be  referable  to  a 
pre-Illinoian  invasion. 

In  northern  Illinois  there  are  certain  deposits  which  need  consideration 
in  this  connection.  The  studies  of  Mr.  Ira  M.  Buell  in  eastern  Winnebago 
County  led  to  the  discovery  of  several  exposures  of  g'lacial  conglomerate 
which  appear  along  the  east  bluff  of  Pock  River.  Bowlder-like  masses  of 
this  conglomerate  have  been  incorporated  in  the  till  of  that  region,  a  good 
illustration  being  found  in  the  cuttings  of  the  Illinois  Central  Railroad, 
immediately  southeast  of  Rockford.  The  firm  cementation,  and  also  a 
deep  orange-colored  stain  presented  by  the  conglomerate  from  which  these 
bowlders  are  derived,  seems  to  have  been  produced  prior  to  the  deposition 
of  the  sheet  of  till  in  which  they  are  embedded.  This  till  is  probably  of 
lowan  age.  It  therefore  remains  to  be  determined  whether  the  conglom- 
erate is  of  lUinoian  age  or  of  still  earlier  date.  There  are  other  deposits 
in  this  region,  noted  by  Buell,  which  favor  the  view  that  there  were  not 

1  See  Arkansas  Geol.  Survey,  Crowleys  Ridge,  Report  for  1889,  Vol.  II,  p.  229. 


110  THE  ILLINOIS  GLACIAL  LOBE. 

less  than  two  ice  invasions  prior  to  the  lowan.  Reference  is  made  to  the 
evidence  fonnd  in  the  occurrence  or  distribution  of  bowlders  of  Waterloo 
quartzite,  a  subject  Avhich  has  been  investigated  in  considerable  detail  by 
Buell  and  discussed  in  a  recent  paper  published  in  the  Transactions  of  the 
Wisconsin  Academy  of  Sciences.^ 

The  earliest  movement  affecting  the  ledges  of  Waterloo  quartzite, 
which  has  been  recognized  by  Buell,  is  interpreted  by  him  to  have  been 
westward.  This  movement  is  indicated  by  the  westward  transportation  of 
bowlders  from  the  quartzite  ledges,  and  farther  south  by  the  occurreiice  in 
the  marginal  portion  of  the  drift  of  Devonian  and  Upper  Silurian  rocks, 
which  could  only  have  been  derived  from  the  east.  Following  the  westward 
movement,  he  thinks  there  is  evidence  of  a  southward  movement,  through 
which  quartzite  bowlders  were  carried  into  northern  Illinois.  He  considers 
the  western  margin  of  the  ice  lobe  which  transported  this  material  to  be 
indicated  by  a  "  belt  of  thickened  stony  till  and  kame-like  gravel  deposits, 
the  fonner  appearing  on  tlie  ridge  surfaces  and  the  latter  spreading  over  the 
lower  level."  This  supposed  line  of  marginal  deposit  has  been  traced  by 
Buell  from  the  point  where  it  emerges  from  beneath  the  Kettle  moraine, 
near  the  line  of  Dane  and  Greene  counties,  Wisconsin,  southward  through 
eastern  Greene  County,  Wisconsin,  into  northeastern  Stephenson  County, 
Illinois.  Quartzite  bowlders  have  been  discovered  in  this  belt  and  over  the 
countr}"  to  the  east  to  points  slightly  beyond  Rock  River,  but  none  were 
found  by  Buell  west  of  this  belt.  They  are  readily  found  as  far  south  as 
the  latitude  of  Freeport  and  Rockford,  but  farther  south  they  are  very  rare, 
and  apparently  represented  only  by  small  fragments.  Buell  thinks  it 
probable  that  the  southward  movement  extended  but  little  beyond  a  line 
connecting  these  cities,  the  scattering  pebbles  to  the  south  being  transported 
perhaps  by  water.  The  southward  movement  is  thought  to  have  been 
followed  b)'  a  southwestward  one  in  southern  Wisconsin,  with  perhaps 
westward  movement  in  southern  Illinois,  by  which  quartzite  bowlders  -wei-e 
carried  southwest  fi-om  the  ledges  slightly  beyond  the  limits  of  the  Kettle 
moraine.  Tliis  invasion  is  referred  to  the  lowan  stage  of  glaciation  by 
Buell,  and  is  correlated  by  him  witli  the  main  loess  deposition.  He  limits 
its  western  extension  to  the  east  border  of  the  loess. 

The  interpretation  made  by  Buell  would  refer  the  earliest  or  westward 


'  Bowlder  tmins  from  the  outcrop  of  thu  Watoiloo  i|uartzite  area,  by  Irii  M.  Bnell :  Trans.  Wis- 
cousiu  Aiad.  Sci.,  Vol.  X,  1891-95,  pp.  405-o0!l. 


SILVERIA  (t)  FORMATION  AND  OTHER  SILT  DEPOSITS.         HI 

movement  to  the  Illinoian  stage,  while  the  southward  movement  is  interpo- 
lated between  the  Illinoian  and  lowan.  If,  therefore,  this  interpretation 
be  correct,  it  affords  no  evidence  of  a  pre-IUinoian  invasion.  The  subject 
of  bowlder  transportation  has  been  studied  so  little  as  yet  that  it  may  be 
unsafe  to  take  the  interpretation  given  by  Buell  as  fiiaal,  although  it  appears 
well  sustained.  On  this  question,  as  well  as  on  that  of  the  age  of  the  con- 
glomerate found  on  the  borders  of  Rock  River,  further  light  is  desirable. 

Hershey  has  recently  discussed  certain  silts  in  northwestern  Illinois, 
which  underlie  the  Illinoian  drift,  as  probable  representatives  of  a  stage  of 
glaciation  preceding  the  Illinoian.^  He  does  not,  however,  refer  the  silt 
deposition  to  a  time  much  earlier  than  the  Illinoian.^  There  is  evidence  of 
erosion  of  this  silt  prior  to  the  ice  invasion  which  deposited  the  Illinoian 
drift.  It  is  possible  that  these  silts  may  be  correlated  with  the  ferruginous 
glacial  conglomerate  along  the  east  side  of  Rock  River,  the  conglomerate 
being  deposited  by  a  stream  and  the  silts  by  a  temporary  lake,  though  there 
is  as  yet  no  adequate  basis  for  such  a  correlation. 

SILVERIA  (?)  FORMATION   AND   OTHER  SILT  DEPOSITS. 

In  the  course  of  the  discussion  of  the  Illinoian  drift  and  of  the  Kansan 
till  sheet,  which  it  overlaps  on  the  west,  frequent  reference  has  been  made 
to  the  occurrence  of  deposits  of  silt  beneath  the  Illinoian.  These  deposits 
are  known  to  be  distributed  very  widely  beneath  the  Illinoian  drift,  but  it 
is  not  known  how  large  a  combined  area  they  cover.  They  appear  to  be 
present  in  conspicuous  amount  beneath  many  streams  of  northwestern  Illi- 
nois, but  are  not  often  exposed  to  view  because  of  their  position  beneath 
the  level  of  the  streams.  They  appear  to  be  less  extensively  developed  in 
western  and  southern  Illinois,  though  not  rare  in  either  district.  Their  best 
development,  so  far  as  known,  is  along  the  line  of  valleys  which  were 
favorably  situated  for  the  development  of  lakes  in  front  of  the  ice,  A'-alleys 
whose  lower  coiu'ses  were  entered  by  the  ice  sheet,  while  their  upper  courses 
remained  for  some  time  uncovered  by  the  ice. 

Hershey  has  proposed  the  name  Silveria  for  deposits  of  this  class  in 
northwestern  Illinois.^     The  necessity  for  a  name  for  such  deposits  will 

'Am.  Jour.  Sei.,  4tli  ser.,  1896,  Vol.  II,  pp.  324-330. 

-As  Hershey  uses  the  word  Kansan  for  the  sheet  which  we  are  discussing  as  the  Illinoian,  the 
reader  may  find  it  somewhat  confusing  to  interpret  his  language.  Hershey,  however,  is  not  at  fault 
in  the  use  of  this  term,  since  his  paper  was  prepared  before  the  uame  Illinoian  had  l)een  introduced. 
He  naturally  inferred,  in  the  absence  of  knowledge  to  the  contrary,  that  the  same  name  should  be 
applied  to  the  sheet  outside  the  lowan  in  northwestern  Illinois  as  has  been  applied  in  southern  Iowa. 


112 


THE  ILLINOIS  GLACIAL  LOBE. 


depend  upon  the  bearing  they  may  have  upon  glacial  history  and  then- 
relation  to  each  other.  Should  it  be  found  that  any  of  them  bear  evidence 
of  a  distuict  stage  of  glaciation  to  which  no  name  has  yet  been  applied,  or 
to  auA'  part  of  geological  time  not  assigned  a  name,  it  would  seem  proper 
to  inti-oduce  a  name.  But  if  they  simpl)^  mark  the  deposits  of  small  lakes 
of  temporary  character  formed  during  an  ice  advance  to  which  a  name  has 
already  been  applied,  it  Avould  seem  better  to  extend  the  name  of  the  ice 
invasion  to  the  silts.  Thus  we  might  speak  of  bm-ied  silts  of  Kansan  age 
or  of  Illinoian  age.  The  relation  to  the  glacial  deposits  would  then  be 
more  clearly  seen  than  if  a  separate  name  were  applied  to  the  silts.  In  the 
case  of  the  silts  which  Hershey  has  named  Silveria  there  appears  to  be 
evidence  that  thej^  do  not  connect  definitely  with  the  advancing  Illinois  ice 
lobe,  for,  as  noted  above,  they  seem  to  have  suffered  some  erosion  prior 
to  the  Illinoian  ice  invasion.     It  therefore  may  be  necessary  to  retain  the 


~  -    "^'^  ^i^^ga^Qgg^'^'*^'''^^^"'^^^^^^'^''  -^-^^^^^ 


^^&^'-"'-'~' 


^— ^^^^^^Zj^ 


:j-- 


a,  Present. soil. 
/',  Loes.s. 
c,  <3td  soil. 

rf.TilldlliLoian). 
e.  Chert,  etc. 

/,  Extr.i-glaci.ll  silt. 

y,  Brown  s.ind. 


FKi.  1. — Section  showing  tlie 


'  Silveria  fonutttiou  "  near  Freeport,  Illinois ;  prepareil  by  O.scar  H.  Hershey.    a  and  *  com- 
l)ine(l  are  the  *'  Silveria. " 


name  Silveria,  but  to  restrict  it  to  deposits  which  are  clearly  of  similar  age 
to  those  examined  by  Hershey.  If,  on  examining  the  silts  of  valleys  in 
other  parts  of  the  region  covered  by  the  Illinois  lobe,  it  is  found  that  a 
similar  interval  of  erosion  separates  their  dei^osition  from  tluit  of  the  Illi- 
noian drift,  the  name  may  be  extended  perhaps  to  such  deposits.  But  if  it 
is  found  that  valleys  contain  silt  deposits  which  immediately  precede  the 
Illinoian  till  sheet  in  date  of  deposition,  it  seems  advisable  to  withhold  the 
name  Silveiia  and  refer  to  them  as  the  silts  of  the  Illinoian  stage.  It  is 
probaljle  that  many  if  not  all  the  valleys  in  which  the  Illinoian  till  sheet 
blocked  tlie  lower  course  and  formed  the  temporary  lakes  contain  deposits 
of  this  latter  class.  It  is  likely,  therefore,  to  be  more  extensive  than  the 
Silveria  formation.  Hershey  recognized  this  restricted  application  of  the 
name,  and  gives  the  extraglacial  silts  a  separate  place  (see  fig.  1). 

In  western  Illinois,  as  was  indicated  above,  there  are  silts  which  appear 


SILVERIA  (?)  FORMATION  AXD  OTHER  SILT  DEPOSITS.         113 

to  nave  been  formed  at  the  Kansau  stage  of  glaciation  by  the  blocking  of 
valleys  which  had  westward  discharge  to  the  Mississippi.  If  this  be  the 
correct  interpretation,  these  silts  can  not  properly  be  termed  Silveria,  for 
they  may  be  mncli  older  than  that  formation  and  their  relation  to  the 
Glacial  series  would  be  more  clear  if  they  were  termed  Kansan  silts. 

The  Silveria  formation  discussed  by  Hershey  "is  a  thick  bed  of  strati- 
fied silt  of  a  nearly  uniformly  dark  bluish-gray  color  with  bands  often 
several  feet  in  thickness  which  are  a  lighter  tint."  But  one  surface  exposure 
has  been  found,  and  is  located  in  a  small  ravine  IJ  miles  south  of  the  city 
of  Freeport,  yet  wells  have  shown  its  occurrence  in  the  valleys  of  nearly 
all  the  streams  in  the  Pecatonica  di'ainage  basin.  At  the  surface  exposure 
"the  upper  portion  is  a  false-bedded,  calcareous  and  ferruginous,  light- 
brown  fine  sand  and  silt,  and  appears  to  represent  the  shore  deposits  of  an 
ancient  lake  in  which  this  formation  was  apparently  laid  down."  Its 
calcareousness  strongly  supports  the  view  that  it  is  a  glacial  silt.  Several 
species  of  sirtail  shells  and  also  fragments  of  partially  decayed  wood  have 
been  collected  by  Mr.  Hershey.  Specimens  of  the  shells,  submitted  to  Dr. 
W.  H.  Dall,  of  the  United  States  Geological  Survey,  are  found  to  represent 
three  difiPerent  species,  with  fragments  of  still  other  species.  These  species 
are  present  in  about  the  following  proportionate  numbers:  Succinea  avara 
50,  Pupa  hlandi  5,  Fyramidula  striatella  2.  Hershey  refers  the  occurrence 
of  this  terrestrial  fauna  in  a  deposit  of  lacustrine  character,  to  the  position 
near  the  shore  of  the  lake. 

This  deposit  appears  to  Have  considerable  bulk  in  the  valleys  of 
Stephenson  County.  In  a  well  3  miles  southwest  of  Freeport,  in  the  old 
valley  of  Yellow  Creek,  it  was  penetrated  to  a  depth  of  150  feet  without 
reaching  the  bottom.  Hershey  estimates  that  if  spread  out  over  the  entire 
surface  of  Stephenson  County,  this  deposit  would  make  a  uniform  layer  at 
least  14  feet  in  depth.  He  estimates  the  total  depth  of  the  superficial 
deposits  of  Stephenson  County  to  be  32^  feet.  It  forms  therefore  nearly 
half  the  bulk  of  these  deposits. 

Above  the  silt  which  Hershey  has  called  the  Silveria  formation  there 
is  another  silt  deposit  separated  from  it  by  an  erosion  unconformity  and 
a  slightly  developed  soil.  This  he  considers  an  extraglacial  lake  deposit 
formed  during  the  advance  of  the  ice  sheet  which  formed  the  overlying  till. 
This  deposit  he  estimates  to  have  an  average  thickness,  if  spread  over  the 
MON  xxxviii 8 


114  THE  ILLINOIS  GLACIAL  LOBE. 

entire  surface  of  Stephenson  County,  of  but  1  foot,  or  only  one-fom-teenth 
the  bulk  of  the  Silveria  formation. 

In  the  vicinity  of  Rock  Island  several  exposures  of  silt  have  been 
found  by  Prof.  J.  A.  Udden  beneath  the  lowest  deposit  of  till,  and  through 
his  kindness  the  writer  has  been  conducted  to  them.  Whether  these 
deposits  are  all  of  similar  age,  and  whether  they  are  earlier  or  later  than 
the  Kansan,  has  not  been  determined.  They  appear  to  be  at  least  as  old 
as  the  maximum  extension  of  the  Illinoian  sheet.  One  of  the  best  exposures 
is  that  made  b}^  a  well  at  the  base  of  the  Mississippi  bluff,  near  Thirty-sixth 
street,  in  Rock  Island.  The  bluff  back  of  the  well  carries  about  40  feet 
of  loess  and  several  feet  of  till  above  the  level  of  the  well  mouth.  The 
exposures  are  not  adequate  to  show  the  age  of  the  till,  though  it  is  probably 
Illinoian.  The  section  of  the  well,  which  was  observed  while  in  process  of 
excavation  both  by  Professor  Udden  and  by  the  writer,  is  as  follows : 

Section  of  well  near  Thirty-sixth  street,  BocTc  Island,  Illinois, 

Feet. 

Yellow  till  (probalily  Illinoian)  5 

Black  muck  (Yarmouth ?) 1 

Brown  till  (leached  2  or  3  feet)  7 

Blue  till  (probably  Kansan) 4 

Black  calcareous  silt,  with  gasteropod  fossils 8 

Black  muck 4 

Green  muck  with  a  few  local  pebbles 5 

Coal  Measures  shale. 

Total 34 

Within  a  mile  east  from  this  exposure,  in  the  city  of  Moline,  a  well 
observed  by  Udden  reached  a  fossiliferous  loess-like  silt  beneath  a  pebbly 
clay  at  a  depth  of  30  feet.  The  well  is  on  the  Mississippi  River  bottom, 
corner  of  Seventh  avenue  and  Fifth  street,  Moline,  at  an  altitude  about  30 
feet  above  the  low-water  mark  of  the  river. 

A  ravine  on  the  range  line  between  sec.  7,  T.  17  N.,  R.  1  W.,  and  sec. 
12,  T.  17  N.,  R.  2  W.,  exposes  the  following  section: 

Section  of  ravine  on  ranr/e  line  between  sec.  7,  T.  17  N.,  R.  1  W.,  and  sec.  12,  T.  17  N., 

R.  2  W. 

Peet. 

Loess 45 

Black  soil 2 

Yellowish-brown  till 12 

Lopss-like  silt,  containing  fossils several  feet 

Coal  Measures  sandstone. 


SILVERIA  (?)  FORMATION  AND  OTHER  SILT  DEPOSITS.         115 

Another  exposure  occurs  in  the  east  bkiff  of  the  Mississippi  near  the 
line  of  Rock  Island  and  Mercer  counties  and  has  the  following  section: 

Section  of  ravine  near  the  line  of  Rock  Island  and  Mercer  counties,  Illinois. 

Teet. 

Loess 25 

Black  soil 2-3 

Till,  mainly  of  blue  color 90 

Loess-like  silt,  very  fossiliferous 12 

Total 130 

The  bottom  of  the  lower  loess  was  not  reached  by  this  ravine.  This 
deposit  differs  from  the  surface  loess  in  containing  a  large  number  of  nodules 
and  tubes  of  partially  solidified  material.  These  have  a  yellowish  color 
and  are  largely  due  to  the  presence  of  iron  oxide. 

Specimens  of  fossils  have  been  collected  by  Udden  from  these  bm-ied 
loess-like  silts  in  Rock  Island  County  as  well  as  from  surface  loess  and 
submitted  to  Dr.  W.  H.  Dall  and  his  assistant,  Mr.  C.  T.  Simpson,  for 
examination.  The  buried  silt  deposits  are  found  to  contain  a  larger  pro- 
portion of  Helicina  occulta  than  the  surface  loess  and  a  smaller  proportion 
of  Succinea  avara.  These  two  species  are  the  most  abundant  ones  in  all  the 
deposits,  whether  surface  loess  or  buried  silt.  With  the  exception  of  the 
exposure  of  the  east  bluff  of  the  Mississippi,  the  only  additional  fossils 
found  in  the  buried  silt  are  Pyra/michda  striatella  and  Piqm  aUicola.  The 
latter  species  is  now  confined  to  the  Rocky  Mountain  region.  The  speci- 
mens collected  from  the  ravine  in  the  east  bluff  of  the  Mississippi,  near  the 
line  of  Rock  Island  and  Mercer  counties,  contain  a  greater  variety,  as 
follows : 

Helicina  occulta  Say;  very  abundant. 

Helicodiscus  lineatus  Say. 

Limnrea  humilis  Say  (variety). 

Pyramidula  perspectiva  Say. 

Pyramidula  striatella  Anth. 

Pupa  armifera  Say. 

Strobilops  labyrinthica  Say. 

Succinea  avara  Say;  less  abundant  than  in  surface  loess. 

Succinea  luteola  Gould. 

Vitrea  arborea  Say  ? 

The  origin  and  relations  of  the  buried  loess-like  silts  of  Rock  Island 
County  remain  to  be   determined.     Whether  they  are  the   deposit  of  an 


116  THE  ILLINOIS  GLACIAL  LOBE. 

extraglacial  lake  formed  in  valleys  in  front  of  tlie  advancing  ice  sheet,  or, 
like  the  svxrface  loess,  have  a  wider  distribution  less  clearl}'^  connected  with 
the  ice  invasion,  is  not  at  present  known.  They  may  be  widely  distributed 
beneath  the  Illinoian  sheet  in  western  Illinois.  In  texture  and  general 
appearance  these  deposits  are  very  similar  to  the  sm-face  loess.  They  are- 
apparently  not  so  compact  as  the  laminated  silts  of  northwestern  Illinois, 
described  by  Hershey  under  the  name  Silveria  formation. 

The  deposits  of  laminated  clay  with  sand  partings,  found  beneath  the 
till  in  central  Adams  County,  Illinois,  have  akeady  been  discussed  as  prob- 
able products  of  an  obstruction  of  an  eastern  tributary  of  the  Mississippi 
by  the  Kansan  invasion  of  the  Keewatin  ice  sheet.  It  is  probable  that 
similar  deposits  fill  the  valleys  of  other  eastern  tributaries  of  the  Mississippi 
in  western  Illinois,  though  as  yet  none  have  been  observed.  The  date  of 
these  laminated  clays,  compared  with  that  of  the  buried  silt  of  Rock  Island 
County,  or  of  the  Silveria  forma,tion  of  Stephenson  County,  is  not  known. 

The  silt  beneath  the  till  at  Pana,  noted  above,  is  so  much  older  than 
the  overlying  till  that  it  can  scarcely  be  considered  an  extraglacial  lacustrine 
deposit  formed  during  the  ice  advance  which  deposited  the  till.  Its  origin 
and  date  are  not  determined. 

In  the  reports  of  the  geology  of  Illinois  there  appear  several  instances 
of  the  occurrence  of  a  plastic  blue  clay,  or  "blue  mud,"  below  the  till  in  the 
vicinity  of  the  glacial  boundary  in  southern  Illinois.^  This  blue  material 
appears  to  be  a  silt  deposit  stained  by  humus.  It  often  contains  much  wood 
and  other  organic  matter.  The  writer  has  not  been  successful  in  finding  an 
exposure  and  can  not  pass  an  opinion  upon  the  character  or  the  origin  of 
the  deposit.  It  is  probable  that  valleys  in  that  region  which  were  obstructed 
by  the  advancing  ice  sheet  were  filled  to  some  extent  by  silt,  but  since  the 
deposit  in  question  contains  wood  and  other  ^'egetal  material  it  apparently 
antedated  the  till  by  a  considerable  interval,  though  it  is  possible  that  the 
accumulation  of  wood  and  organic  matter  is  due  to  the  introduction  of  this 
material  by  currents  of  water  during  the  silt  deposition,  and  not  by  the 
gi'owth  of  vegetation  on  the  silt  after  the  completion  of  the  deposition. 

A  detailed  section  of  the  material  penetrated  by  the  Isabella  Thompson 


I  Gool.  Illinois,  Vol.  I,  pp.  299,  300,  31G ;  Vol.  Ill,  pp.  75, 86, 87, 103. 


SILVERIA  (?)  FORMATION  AND  OTHER  SILT  DEPOSITS.  H? 

coal  shaft  near  Sparta  in  eastern  Randolph  County,  has  been  published  by 
Prof.  J.  M.  Nickles.^     The  Pleistocene  deposits  are  as  follows: 

Section  of  Pleistocene  beds  penetrated  by  the  Isabella  Thompson  coal  shaft  near  Sparta, 

Illinois. 

Feet. 

Soil  and  clay 3 

Yellow  clay 17 

Blue  clay ^.. 3 

Quicksanil 4 

Silt 2 

Gravel 4 

Silt  • — : 3^ 

Sand  and  gravel 6i 

Drab  or  mouse-colored  silt 11 

Concrete  or  bardpan 4 

Fine  giay  sand 6 

Sand  and  clay  mixed 6^ 

Silt 2i 

Bowlder  clay 6i 

Fine  gravel 4 

Bowlder  clay If 

Laminated  clay,  containing  wood 5 

Tufcil  drift 90 

In  this  section  there  appears  to  have  been  an  alternation  of  glacial  and 
lacustrine  deposition  without  distinct  evidence  of  long  interruption.  The 
laminated  clay  at  the  base  of  the  series  contains  a  large  amount  of  wood, 
specimens  of  which  have  been  sent  to  the  writer  by  Professor  Nickles,  but 
which  await  specific  identification. 

Borings  for  coal  and  water  in  the  Big  Muddy  Valley  in  the  vicinity 
of  Murphysboro  usually  penetrate  a  large  amount  of  sand.  As  this  valley 
does  not  appear  to  have  been  obstructed  by  the  ice  invasion  the  sand  can 
not  be  referred  with  any  certainty  to  lacustrine  conditions.  It  seems  more 
probable  that  it  is  an  indicator  of  the  weakness  of  the  currents  of  the  stream. 

The  tributaries  of  the  Wabash  in  southeastern  Illinois  are  usually 
filled  with  sand  or  silt,  and  these  open  southward  in  such  manner  as  to 
avoid  obstruction  by  the  advancing  ice  sheet.  The  filling  probably  may 
be  taken  as  an  index  of  the  weakness  of  the  currents  of  the  stream  just 
before  the  ice  invasion.  It  may  be  remarked  in  this  connection  that  the 
filling  of  the  valleys  of  southern  Illinois  apparently  opposes  the  somewhat 
popular  hypothesis  that  there  was  a  period  of  high  elevation  and  vigorous 

'  Final  report  Illinois  Board  World's  Fair  Commissioners,  1893,  pp.  200,  201. 


118  THE  ILLINOIS  GLACIAL  LOBE. 

stream  action  iu  this  part  of  the  Mississippi  Basin  just  before  the  first  ice 
invasion. 

The  character  of  the  deposits  beneath  the  till  in  the  valleys  of  south- 
western Indiana  has  not  received  attention,  for  that  region  has  been  given 
only  a  hasty  reconnaissance.  The  Wabash  Valley  is  filled  to  considerable 
depth  with  sand  and  fine  gravel,  but  this  rnay  be  in  large  part  derived  fi-om 
the  Wisconsin  glacial  drainage.  Its  rock  floor  stands  75  to  100  feet  below 
the  present  stream  at  the  points  where  tested  by  borings.  The  tributaries 
show  a  coiTespondingly  low  rock  floor,  but  their  filling  in  the  district  outside 
the  Wisconsin  diift  is  not  so  coarse  as  that  along  the  Wabash. 


CHAPTER  V. 
THE  YARMOUTH  SOIL  AND  WEATHERED  ZONE. 

The  occurrence  of  a  definite  soil  and  weathered  zone  between  the  over- 
lapping portions  of  the  lUinoian  and  Kansan  till  sheets  has  been  so  fully 
set  forth  in  the  discussion  of  the  Illinoian  drift  border  that  but  few  further 
remarks  seem  necessary.  The  name  Yarmouth,  as  above  indicated,  is  from 
the  village  in  Des  Moines  County,  Iowa,  where  the  evidence  of  a  prolonged 
interval  between  the  till  sheets,  now  known  as  Kansan  and  Illinoian,  was 
first  recognized.  It  remains  to  be  determined  whether  the  occasional 
instances  of  soil  reported  to  occur  between  sheets  of  till  in  portions  of  the 
Illinoian  area  east  of  the  limits  of  the  Keewatin  ice  sheet  are  to  be  referred 
to  the  Yarmouth  interglacial  stage.  Further  light  is  also  necessary  to 
determine  whether  all  instances  of  buried  soils  within  the  region  of  overlap 
of  Illinoian  upon  Kansan  till  are  to  be  referred  to  the  Yarmouth  stage.  For 
example,  the  buried  soil  in  the  gas  belt  west  of  Letts  may  prove  to  be  of 
earlier  date  than  the  Yarmouth,  though  it  seems  quite  probable,  as  above 
noted,  that  it  is  found  in  a  valley  which  had  been  cut  in  the  Kansan  drift 
prior  to  the  Illinoian  invasion. 

WEATHERING  OF  THE  BURIED  KAKSAIST  DRIFT. 

Among  the  several  evidences  of  a  long  interval  between  the  Kansan 
and  Illinoian  invasion,  that  of  weathering  is  the  most  common  and  perhaps 
the  most  decisive.  As  shown  in  the  sections  given  above,  there  is  found  to 
have  been  a  general  leaching  of  the  sheet  of  calcareous  Kansan  till  to  a 
depth  of  4  to  6  feet  prior  to  the  deposition  of  the  Illinoian  sheet  of  drift. 
Accompanying  the  leaching  the  upper  portion  of  the  Kansan  drift  was 
weathered  to  a  brown  and  in  places  reddish-brown  color.  The  brown  color 
extends  much  below  the  limits  of  the  leaching,  there  being  not  a  few  instances 
in  which  it  extends  to  a  depth  of  25  or  30  feet,  and  it  is  rarely  less  than  12 
to  15  feet.     The  reddish-brown  stain  usually  extends  only  to  a  depth  of  2 

119 


120  THE  ILLINOIS  GLACIAL  LOBE. 

or  3  feet  from  the  surface.  •  The  Kansau  till,  as  noted  above,  is  commonly 
characterized  by  vertical  fissures  and  shows  a  tendency  to  fracture  in  rec- 
taug'ular  blocks.  Along  the  lines  of  the  fissures  the  brown  stain  often 
extends  some  distance  into  the  blue  or  unoxidized  portion  of  the  sheet,  thus 
extending  the  limits  of  oxidation  still  lower  than  the  general  zone  of  oxida- 
tion. As  ]3reviously  stated,  the  amount  of  leaching  and  oxidation  at  the 
Yarmouth  stage  appears  to  be  about  as  great  as  in  all  post-Illinoian  time. 

There  are,  as  above  noted,  places  where  the  lUinoian  till  rests  directly 
upon  an  unleached  Kansau,  but  in  such  places  the  oxidation  and  vertical 
Assuring  are  present  to  testify  to  the  changes  effected  in  the  Kansan  sheet. 
The  absence  of  a  leached  zone  at  the  top  of  the  Kansan  in  such  places  is 
readily  accounted  for  through  removal  by  the  Illinoian  ice  sheet.  It  is 
perhaps  more  remarkable  that  the  leached  zone  is  so  well  preserved  than 
that  it  should  have  been  occasionally  i-emoved  by  the  Illinoian  ice  invasion. 

BURIED  SOIL,  PEAT,  ETC. 

The  accumulation  of  beds  of  peat  at  the  surface  of  the  Kansan  drift, 
prior  to  the  Illinoian  ice  invasion,  constitutes  as  impressive  an  evidence  of  a 
prolonged  interval  as  the  leached  and  reddened  surface.  In  the  Yarmouth 
section  the  peat  has  a  depth  of  15  feet  while  underlying  beds  of  sandy 
clay,  and  sand  carrying  bits  of  wood,  probably  also  to  be  classified  as  inter- 
glacial,  extend  the  depth  of  the  Yarmouth  deposits  to  43  feet.  Buried  soil 
of  black  color  and  beds  of  peat  have  attracted  the  attention  of  well  diggers 
in  nearly  every  township  of  the  region  of  overlap  in  southeastern  Iowa, 
and  specimens  of  the  peat  obtained  from  wells  are  preserved  at  many  of  the 
farm  houses.  Along  the  border  of  the  Illinoian  the  soil  is  usually  found  at 
about  the  general  level  of  the  upland  portion  of  the  Kansan  drift  surface 
and  may  be  referred  with  confidence  to  the  Yarmouth  stage,  but  occa- 
sionally it  occurs  below  that  level.  In  such  instances,  so  far  as  the  writer 
is  aware,  no  soil  has  been  noted  at  a  level  corresponding  to  the  upland  sur- 
face of  the  Kansan.  The  presumption  is  that  the  soil  occurs  in  interglacial 
valleys  which  had  been  cut  into  the  Kansan  prior  to  tlie  Illinoian  invasion, 
and  that  the  entire  till  deposit  above  the  soil  is  Illinoian.  The  erosion  thus 
indicated  commonly  shows  a  depth  of  less  than  50  feet  and  harmonizes  with 
the  depth  of  i)re-IlHnoian  valley  erosion  of  the  drift  outside  the  limits  of  the 
Illinoian  drift.     There  is,  however,  an  occasional  example  of  the  occurren'ce 


EROSION  OP  THE  KANSAS  DEIFT  SHEET.  121 

of  a  buried  soil  in  the  district  west  of  the  hmits  of  the  Illinoian,  either  under- 
neath or  within  the  Kansan  drift.  This  feature  makes  it  necessary  to  leave 
open  the  question  of  the  age  of  buried  soils  within  the  Illinoian  area  which 
occur  at  a  level  below  the  general  elevation  of  the  outlying  Kansan  di'ift. 

EROSIO?^^  OF  THE  KANSAS  DRIFT  SHEET. 

The  pre-lUinoian  erosion  of  the  Kansan  till  sheet  is  a  third  evidence  of 
the  great  length  of  the  Yarmouth  interglacial  stage.  Such  erosion,  as  just 
noted,  is  suggested  within  the  limits  of  the  Illinoian  by  the  occuirence  of  a 
buried  soil  below  the  general  level  of  the  Kansan  di'ift  surface.  But 
evidence  may  be  found  in  the  portion  of  the  Kansan  drift  lying  outside  the 
limits  of  the  Illinoian  which  is  not  at  all  open  to  question.  The  evidence 
first  to  attract  notice  was  that  of  the  relative  degrees  of  erosion  displayed 
by  the  Illinoian  and  Kansan  di'ift  sheets.  Prior  to  the  discovery  of  the 
extension  of  the  Illinois  lobe  into  southeastern  Iowa  it  had  been  noted  by 
Chamberlin,  as  well  as  by  the  writer,  that  southern  Iowa  presents  a  more 
eroded  appearance  than  western  Illinois  and  the  southeastern  counties  of 
Iowa,  and  the  matter  was  discussed  as  a  remarkable  feature.  In  the  district 
outside  the  limits  of  the  Illinoian  the  original  di'ift  plain  is  preserved  only 
in  narrow  strips  along  divides,  estimated  to  comprise  scarcely  one-fourth  of 
the  surface,  while  in  the  district  covered  by  the  Illinoian  drift  the  remnants 
are  far  more  extensive,  comprising  apparently  more  than  half  the  surface. 
The  branching  of  drainage  lines  is  also  carried  to  markedly  greater  matui'ity 
in  the  Kansan  than  in  the  Illinoian  drift. 

Definite  means  for  determining  the  amount  of  pre-Illinoian  erosion  of 
the  Kansan  is  afiForded  by  a  study  of  the  valleys  in  Kansan  drift  which 
connect  with  the  abandoned  valley  of  the  Mississippi,  which  was  occupied 
at  the  Illinoian  invasion.  These  embrace  the  valleys  of  West  Crooked 
Creek,  Skunk  River,  and  Big  Cedar  Creek.  Valleys  farther  north  have 
generally  been  greatly  modified  by  the  lowan  invasion,  and  hence  do  not 
furnish  good  illustrations.  It  is  found  that  the  three  valleys  just  noted  have 
been  cut  at  their  points  of  connection  with  the  abandoned  valley  to  a  depth 
of  about  50  feet  below  neighboring  uplands  and  to  widths  of  about  three- 
fourths  of  a  mile,  1^  miles,  and  1  mile,  respectively,  at  the  time  the  Missis- 
sippi was  occupying  this  abandoned  channel,  i.  e.,  at  the  Illinoian  stage  of 
glaciation.     This  width  is  two  or  three  times  that  of  the  inner  valleys,  which 


122  THE  ILLINOIS  GLACIAL  LOBE. 

are  now  cut  far  below  the  level  of  the  pre-Illinoiau  valleys,  but  repre- 
sents nearly  as  much  removal  of  material,  and  the  removal  was  probably 
effected  at  a  lower  gradient,  i.  e.,  under  less  favorable  conditions  than  are 
now  afforded.  In  this  comiection  it  should  be  noted  that  no  CAndence  has 
been  found  that  the  gradient  of  the  streams  was  increased  until  after  the 
lowan  stage  of  glaciation.  The  inner  valleys  represent,  therefore,  post- 
lowan  rather  than  post-Illinoian  excavation.  But  this  fact  does  not  appar- 
ently set  aside  the  estimate  given  above,  for  if  the  pre-Illinoian  valley 
excavation  had  not  reached  the  level  of  the  channel  opened  by  the  Missis- 
sippi at  the  Illinoian  stage  of  glaciation,  that  valley  would  have  furnished 
a  more  du-ect  and  presumably  more  favorable  line  of  discharge  for  all  these 
streams  than  their  present  line.  The  featm-es  along  the  present  line  of  dis- 
charge for  the  thi-ee  streams  under  consideration  (eastward  through  Skunk 
River)  strongly  support  the  view  that  a  pre-Illinoian  valley  was  formed  in 
the  lower  course  of  Skmak  River.  A  broad  terrace  borders  the  portion  of 
the  valley  below  the  point  where  Skunk  River  crosses  the  abandoned  valley 
at  Rome,  which  stands  sufficiently  low  to  have  afforded  a  line  of  discharge 
for  the  portion  of  the  valley  west  of  the  abandoned  channel.  This  would 
have  been  blocked  at  the  Illinoian  ice  invasion,  but  not  necessarily  con- 
cealed or  greatly  filled  by  Illinoian  drift.  Upon  the  withdi-awal  of  the  ice, 
if  it  chanced  to  stand  slightly  lower  than  the  Illinoian  course  of  drainage,  it 
would  receive  the  post-Illinoian  di-ainage  and  become  the  line  of  a  reestab- 
lished stream. 

There  is  near  the  mouth  of  Skunk  River  an  exceptionally  clear  illustra- 
tion of  the  work  of  that  stream  in  the  Yarmouth  interglacial  stage.  By 
reference  to  fig.  4  it  will  be  seen  that  a  valley  or  depression  turns  away 
from  Skunk  River  at  Augusta  and  leads  southward  to  Lost  Creek.  This 
valley  is  more  than  a  mile  in  width  and  30  feet  or  more  in  depth,  and  is 
excavated  in  the  Kansan  till.  Evidently  it  was  opened  by  Skunk  River 
after  the  Kansan  stage  of  glaciation  and  before  the  Illinoian  stage.  Whether 
it  carried  the  whole  or  only  a  part  of  the  stream  is  not  yet  known.  The 
northern  end  has  received  only  a  thin  coating  of  Illinoian  drift.  The 
southern  end  received  a  sufficiently  heavy  deposit  of  that  drift  to  prevent 
its  subsequent  use  as  a  drainage  line.  Since  the  Illinoian  stage  of  glacia- 
tion the  entire  drainage  of  the  river  has  been  directly  eastward  into  the 
Mississippi.      Low   swells  of  Illinoian  drift   occupy  the   south   end  of  the 


ORGANIC  EEMAINS,  ]23 

valley  and  show  clearly  that  there   has  been  no  valley  excavation  there 
since  they  were  formed. 

The  valley  of  Lost  Creek  in  Lee  County,  Iowa  (see  fig.  4),  though 
lying  wholly  within  the  limits  of  the  Ilhnoian  drift,  bears  evidence  of  having 
been  occupied  and  largely  excavated  by  a  pre-Illinoian  stream.  It  presents 
a  shallow  trough  cut  in  Kansan  drift,  which  is  covered,  but  not  greatly 
concealed,  by  Illinoian  drift.  Low  swells  of  till  formed  at  the  lUinoian 
invasion  occm-  on  its  slopes  and  bottom,  thus  proving  its  pre-Illinoian  exca- 
vation. This  valley  is  about  one-half  mile  in  width  and  30  to  50  feet  in 
depth,  and  holds  this  size  nearly  up  to  the  head,  which  is  found  in  the 
marginal  ridge  of  Illinoian  drift.  It  seems  probable  that  prior  to  the  Illi- 
noian invasion  its  drainage  basin  was  much  more  extensive  than  at  present. 
This  affords  an  illustration  of  a  partially  reestablished  stream.  This  vallej?- 
and  that  of  the  lower  course  of  Skunk  River  are  exceptional,  for  as  a  rule 
the  pre-Illinoian  tributaries  of  the  Mississippi  were  so  completely  filled  at 
the  Illinoian  invasion  that  the  post-IUinoian  drainage  was  opened  along 
new  lines.  It  is  probable  that  the  portion  of  the  Mississippi  between  Mus- 
catine and  Fort  Madison,  Iowa,  is  reestablished  along  a  pre-Illinoian  and 
also  pre-Glacial  line. 

ORGAlSriC    REMAINS. 

As  yet  no  specific  identifications  of  the  wood  and  smaller  plants  found 
at  the  Yarmouth  horizon  have  been  made,  unless  some  of  those  reported  by 
McG-ee  from  northeastern  Iowa  have  this  horizon.  The  wood  appears  on 
a  superficial  examination  to  be  coniferous  and  largely  red  cedar.  It  is 
planned  to  have  careful  examinations  made  in  the  near  future  to  ascertain 
the  bearing  the  plants  may  have  on  the  climate  at  the  Yarmouth  intergla- 
cial  stage.  It  should  be  considered,  however,  that  the  plants  found  in  the 
peat  were  presumably  living  just  before  the  culmination  of  the  Illinoian 
invasion,  and  may  not  aff'ord  a  true  index  of  the  interglacial  stage ;  for  a 
general  lowering  of  temperature  probably  preceded  as  well  as  accompanied 
the  culmination  of  the  ice  sheet.  Possibly  a  deposit  will  yet  be  found  in 
which  plant  remains  occur  which  were  buried  in  the  middle  part  of  the 
interglacial  period.  The  specimens  of  wood  noted  in  the  clay  beneath  the 
bed  of  peat  at  Yarmouth  may  have  been  buried  at  a  sufliciently  early  date 
to  be  unafiPected  by  the  Illinoian  glaciation.  Unfortunately  no  specimens 
of  that  wood  are  now  available. 


124  THE  ILLINOIS  GLACIAL  LOBE. 

The  animal  remains  (rabbit  and  skunk,  see  p.  42)  found  in  tlie  peat  at 
Yai-mouth  show  a  remarkable  state  of  preservation,  the  marrow  of  the  bones 
being  still  preserved,  as  noted  in  the  examination  by  Dr.  F.  W.  True.  This 
is  perhaps  no  more  remarkable  than  the  state  of  preservation  of  some  speci- 
mens of  the  wood  from  the  same  horizon.  Several  of  the  wood  specimens 
have  been  found  to  take  fire  as  readily  as  the  wood  from  our  living  forests. 
In  not  a  few  cases  within  the  writer's  notice  leaves  of  grasses  or  sedges 
have  been  found  in  a  fair  state  of  preservation.  Instances  of  the  occur- 
rence of  leaves  of  oak  or  other  deciduous  trees  have  been  repoi-ted  to  tlie 
Avriter  from  the  Yarmouth  horizon,  but  none  have  come  under  his  personal 
observation.  The  character  of  the  hfe  of  this  interglacial  stage  is  a  field 
promising  much  of  interest,  but  which  as  yet  is  scarcely  at  all  developed. 


(CHAPTER   VI. 
THE  SANGAMON  SOIL  AND  WEATHERED  ZONE. 

Between  the  disappearance  of  the  IlHnoian  ice  sheet  and  the  deposi- 
tion of  the  lowan  till  and  loess  there  occurred  an  interval  of  deglaciation 
about  as  marked  as  that  between  the  Kansan  and  Illinoian  stages  of  gla- 
ciation,  a  period  marked  by  leaching  and  oxidation  of  the  Illinoian  drift,  of 
peat  and  soil  accumulation,  and  of  erosion.  This  interval  was  long  since 
brought  to  notice  by  Prof  A.  H.  Worthen  in  his  report  on  Sangamon  County, 
Illinois.^  For  this  reason,  and  because  of  the  conspicuous  development  in 
the  Sangamon  drainage  basin,  it  seems  appropriate  to  name  it  the  Sangamon 
interglacial  stage.  This  name  was  suggested  by  the  writer  in  a  paper  pre- 
sented before  the  Iowa  Academy  of  Sciences  in  December,  1897. 

The  following  section,  published  by  Worthen,  was  furnished  him  by  a 
well  digger,  Joseph  Mitchell,  who  had  dug  many  wells  in  the  northwest 
part  of  Sangamon  County  and  in  the  adjoining  jjortion  of  Menard  County:^ 

Generalised  section  of  xcells  northwest  of  Springfield,  Illinois. 

i'eet. 

Soil 1-2 

Yellow  clay 3 

WWtisli  (gray  ?)  jointed  clay,  with  shells .'. 5-  8 

Black  muck  with  fragments  of  wood 3-  8 

Bluish  colored  bowlder  clay _ y-10 

Gray  hardpan  (very  hard) 2 

Soft  blue  clay,  without  bowlders , 20-40 

This  section  represents  the  formations  beneath  the  upland  plain  near 
the  western  edge  of  the  Sangamon  watershed  at  an  altitude  200  feet  or 
more  above  the  level  of  the  mouth  of  the  Sangamon.     Worthen  remarks 

'  Geol.  of  Illinois,  Vol.  V,  1873,  jip.  306-319.  -Op.  cit.,  p.  307. 

125 


126  THE  ILLINOIS  GLACIAL  LOBE. 

that  the  fossiliferous  clay  of  the  section-  is  undoubtedly  loess.  He  calls 
attention  also  to  the  prevalence  of  conditions  suitable  for  the  growth  of 
an  arboreal  vegetation  jjrior  to  the  deposition  of  the  loess. 

In  the  section  just  given,  the  black  soil  appears  to  be  the  representative 
of  the  Sangamon  interglacial  stage.  But  this  interglacial  stage,  like  the 
Yarmouth  stage,  is  often  represented  by  a  leached  and  slightl}-  reddened 
till  surface,  unaccompanied  by  black  muck.  These  two  phases  seem  to  lie 
mutually  exclusive,  there  being  but  slight  reddening  of  the  till  surface 
where  the  black  muck  is  present,  or  but  slight  accumulations  of  black  muck 
^'N'hei'e  the  reddening  of  the  till  is  pronounced.  The  black  muck  is 
developed  in  portions  of  the  uplands  where  the  surface  is  very  level  and 
conditions  for  drainage  are  defective,  while  the  reddened  soil  is  developed 
on  the  more  undulatory  tracts,  where  a  fair  condition  of  di-ainage  probablv 
existed.  The  black  muck  phase  is  common  in  the  Sangamon  Basin,  and 
also  in  the  northern  part  of  the  white  clay  district  of  southern  Illinois,  and 
southwestern  Indiana  just  outside  the  limits  of  the  Shelby ville  drift  sheet. 
In  western  Illinois  and  southeastern  Iowa  it  has  a  more  restricted  develop- 
ment, for  the  sui-face  there  is  generally  more  elevated  and  better  situated 
for  the  development  of  drainage  lines  than  in  the  districts  first  mentioned. 
In  southern  Illinois  and  southwestern  Indiana  and  throughout  much  of 
western  and  northwestern  Illinois,  the  reddened  till  surface  is  a  conspicuous 
feature. 

In  certain  areas  an  alternation  of  sand  with  peaty  beds  has  been  found 
between  the  lowan  loess  and  the  Illinoian  till.  This  phase  is  apparently 
restricted  to  the  borders  of  valleys  where  stream  action  has  probably  been 
influential  but  with  intermittent  activity,  the  sand  being  deposited  b}'  the 
streams,  while  the  peat  was  accumulated  at  times  when  the  streams  failed 
to  cover  the  land. 

The  accompanying  views,  PI.  X,  A  and  B,  taken  in  cuttings  along  the 
Santa  Fe  Railway  in  eastern  Knox  County,  Illinois,  show  a  dark  soil  (b)  at 
the  junction  of  the  loess  (a)  and  Illinoian  till  (c).  In  the  exposures  seen  in 
these  views,  acid  tests  show  the  till  to  have  been  leached  to  a  depth  of 
about  4  feet  below  the  dark-colored  soil.  The  overlying  loess  is  calcareous 
at  base.  The  leaching,  therefore,  took  place  prior  to  the  loess  deposition  in 
connection  with  the  development  of  the  soil.     The  depth  of  leacliing  noted 


U.    S.    GEOLOGICAL  SURVEY 


MONOGRAPH  XXXVIII       PL.    X 


A.      NEAR    VIEW    OF    SANGAMON    SOIL    IN     KNOX     COUNTY,    ILLINOIS. 
(a)   Loess,  partly  eroded,  4  feet;   {!>)   Sangamon  soil,  1  foot;   (c)   lllmoian  drift,  4  feet. 


IJ.      MORE    DISTANT   VIEW    OF   SANGAMON    SOIL    IN    KNOX    COUNTY,    ILLINOIS, 
(a)  Loess,   12  feet;   (/j)   Sar^garpon  soil,  2  feet;   (c)   lliinoian  drift,  40  feet. 


THE  SANGAMON  SOIL  AND  WEATHEEEU  ZONE.  127 

in  this  railway  cutting  represents  about  the  average  depth  found  in  the  interior 
portions  of  the  district  covered  by  the  Ilhnoian  drift.  Along  the  borders 
of  the  drift,  as  previously  noted,  the  Illinoian  till  is,  in  places,  noncalcare- 
ous  tlu'oughout  its  entire  depth,  and  seems  to  be  made  up  largely  of  the 
leached  portion  of  the  Kansan  drift  which  it  had  overridden.  Some  care 
must  be  exercised,  therefore,  in  deciding  upon  the  amount  of  leaching  which 
has  taken  place  since  the  Illinoian  ice  sheet  disappeared. 

In  northern  Cumberland  County,  Illinois,  a  short  distance  north  of 
Greenup,  Professor  Chamberlin  and  the  writer  examined'  exposures  of  the 
Sangamon  soil  in  which -branching-  root-like  extensions  of  the  soil  penetrate 
several  inches  into  the  underlying  subsoil.  These  are  thought  to  mark  the 
former  presence  of  forests  on  that  soil. 

In  a  few  places  peat  beds  of  considerable  depth  have  been  found  at 
this  soil  horizon.  Some  of  the  best  instances  occur  a  short  distance  west 
of  the  region  in  which  the  section  reported  by  Worthen  is  found.  The  coal 
shaft  at  Ashland,  Illinois,  near  the  line  of  Sangamon  and  Cass  counties, 
shows  the  following  series  of  di'ift  beds : 

Section  of  the  drift  beds  in  a  coal  shaft  at  Ashland,  Illinois. 

Feet. 

Black  soil 1^ 

Loess  of  yellow  color 1 0 

Loess  of  blue  color 2 

Peat  and  black  sandy  slush 22 

Bluish  gummy  clay 20 

Yellow  till 30 

Total  drift 85 

At  the  air  shaft  sand  was  found  beneath  the  peat  in  the  place  of  the 
blue  gummy  clay.  At  Virginia,  Illinois,  a  well  made  by  Mi*.  Oldridge 
entered  a  bed  of  peat  at  the  base  of  the  loess  at  about  15  feet  and  continued 
in  it  to  a  depth  of  28  feet,  beneath  which  a  blue  clay  was  entered. 

An  instance  of  the  occurrence  of  animal  remains  in  the  basal  portion 
of  the  loess,  immediately  above  a  deposit  of  peat,  probably  Sangamon,  was 
long  since  brought  to  notice  by  Mr.  Pratt,  of  Davenport.^  In  a  railway 
cutting  made  by  the  Chicago,  Rock  Island  and  Pacific  Company,  in  the 

'  Proc.  Davenport  Acad.  Sci.,  1876,  p.  96,  PI.  XXXII.  See  also  Geol.  of  Iowa,  by  C.  A.  White, 
Vol.  1, 1870,  p.  119. 


128  THE  ILLINOIS  GLACIAL  LOBE. 

west  part  of  Davenport,  Iowa,  the  following  beds  are  exposed,  as  reported 
by  Mr.  Pratt,  -who  examined  the  exposure  while  the  excavation  was  fresh : 

Section  in  railway  cutting  near  Davenport,  Iowa. 

Feet. 

1.  Ordinary  prairie  soil,  altitude  167  feet  above  Mississippi  River 1 

2.  Loess,  iron  stained  and  distinctly  laminated  with  laminiB  curved  and  in  places  interbedded 

with  thin  layers  of  sand;  the  deposit  also  contains  small  calcareous  nodules  and  shells  of 
the  genera  Succinea,  Helicina,  and  Pupa 20 

3.  Bluish-gray  clay,  containing  a  few  shells  like  those  of  No.  2;  a  tusk,  several  teeth,  and  other 

portions  of  Elephas  primigenius  (?)  were  found  just  at  the  junction  between  JS'os.  2  and  3...  3-5 

4.  Bed  of  brown  peat  in  which  the  peat  moss,  Hypnum  aduncum,  was  sufficiently  well  preserved 

to  be  identified;  quantities  of  much  decomposed  coniferous  wood  were  also  distributed 
through  this  bed - 1 

5.  Dark-brown  soil,  resembling  the  peat,  but  more  decomposed 2 

6.  Blue    clay,  very  Tenacious,  containing  sand,   gravel,    and  small   bowlders,  many  of   them 

distinctly  glacier  scratched,  extending  beneath  base  of  cutting. 

The  peat  bed,  Avith  its  associated  soil  and  silts,  is  reported  to  have  been 
exposed  for  a  distance  of  30  or  40  rods.  Concerning  it  Dr.  C.  A.  "White 
remarks:^  "  This  deposit  is  quite  remarkable  in  many  respects ;  in  none 
more  so  perhaps  than  in  the  fact  that  the  bed  of  peat  rests  upon  a  bed  of 
clayey  silt  and  is  in  turn  covered  by  a  similar  but  much  deeper  one,  these 
varying  conditions  evidently  haAang  been  produced  by  the  shiftings  of  the 
adjacent  and  then  sluggish  river  in  that  very  early  period  of  its  postglacial 
history." 

The  Sangamon  soil  has  been  exposed  by  some  of  the  streams  within 
the  limits  of  the  Wisconsin  di-ift,  notably  on  the  Embarras  and  Kaskaskia 
rivers  and  tributaries  of  the  Illinois.  It  is  found  below  loess  or  white  clay, 
which  in  turn  lies  beneath  the  till  of  the  Wisconsin  di'ift.  Two  excellent 
exposures  on  Farm  Creek,  east  of  Peoria,  Illinois,  are  shown  in  PL  XI, 
figs.  A  and  B.  In  the  first  (A)  the  soil  is  not  shown,  but  there  is  a  deeply 
leached  and  weathered  zone  at  the  top  of  the  Illinoian.  In  the  second  (B) 
there  is  a  bed  of  peat  resting  upon  silt  which  bears  some  resemblance  to  the 
overlying  lowan  loess  in  texture,  but  is  not  so  calcareous  and  is  of  a  deeper 
brown  color.  Whether  it  is  similar  in  origin  to  the  loess  can  scarcely  be 
decided.  The  writer  also  is  inclined  to  question  whether  the  silt  below  peat 
in  the  Davenport  section  just  described  should  be  referred  to  the  lowan 
loess.  Beneath  the  silt  which  underlies  the  peat  shown  in  fig.  B  there  is 
Illiuoian  till,  and  this  is  leached  to  a  depth  of  3  to  4  feet.     This  section 

^Op.  cit.,p.  120. 


U.   S.   GEOLOGICAL  SURVEY 


MONOGRAPH  XXXVIII       PL.   XI 


uA^a,iii,a3sat.t^aS8^fe^Mh^'^.  ,^, ,  -'  %i^.^.. 


.1       EXPOSURE  ON    FARM    CREEK,    7    MILES   EAST  OF    PEORIA,    ILLINOIS, 

(a)  Bloommgton  gravel  terrace,  8  feet;   (6)   Shelbyville  till  sheet,  14  feet;   (cl   lowan  loess,  10  feet;   (d)  lllinoian  till, 
^View  taken  by  Dr.  Samuel  Calvin,  May,  1898.) 


B      EXPOSURE    IN    A    RAILWAY   CUTTING   ON    THE    TOLEDO,    PEORIA    AND    WESTERN    RAILWAY,   7    MILES   EAST 

OF   PEORIA,    ILLINOIS. 

(a)  Bloomington  gravel  and  cobble  on  slope,  6  feet;  (6)  Shelbyville  till  sheet,  8  feet;  (c)  lowan  loess,  6  feet;  (d)  Sangamon  peai  bed, 
3  to  5  feet;  (ei  Silt  below  peat,  2  to  5  feet.  Below  the  silt  there  is  lllinoian  till  leached  and  weathered  at  top,  4  feet,  beneatn  which 
It  IS  calcareous.      (View  taken  by  Dr.  Samuel  Calvin,  May,   1898.) 


THE  SANGAMON  SOIL  AND  WEATHERED  ZONE.  129 

seems  to  indicate  that  for  a  time  after  the  Illinoian  sheet  was  exposed  to 
atmospheric  action  the  drainage  conditions  were  good,  but  that  subse- 
quently they  became  imperfect  and  the  peat  was  formed.  The  possible 
relationship  between  the  lower  silt  and  the  gumbo  of  the  Mississippi  Basin  is 
discussed  in  connection  with  the  latter  deposit  (p.  32). 

The  wood  found  in  association  with  the  Sangamon  soil  and  peat,  like 
that  of  the  Yarmouth,  appears  to  be  largel}^  coniferous.  Wherever  identi- 
fications have  been  attempted  such  woods  have  been  found  to  occur,  and 
specimens  not  critically  examined  have  the  aspect  of  the  coniferous  rather 
than  the  deciduous  varieties  of  wood.  The  aspect  of  the  flora  is  decidedly 
boreal.  However,  as  noted  in  connection  with  the  discussion  of  the  vege- 
tation found  in  the  Yarmouth  soil,  it  is  necessary  to  guard  against  the 
inference  that  the  vegetal  remains  preserved  in  the  peat  and  mucky  portions 
of  the  soil  furnish  an  index  of  the  climatic  conditions  throughout  the  entire 
interglacial  stage.  They  pertain  only  to  the  close  of  that  stage  when  gla- 
cial conditions  were  being  inaugurated,  and  may  have  an  aspect  very  dif- 
ferent from  that  of  plants  which  grew  in  the  midst  of  an  interglacial  stage. 

Slight  exposures  of  the  Sangamon  soil  and  weathered  zone  are  to  be 
seen  on  nearly  every  hillside  within  the  limits  of  the  Illinoian  drift  where 
erosion  has  opened  a  fresh  exposure  low  enough  to  reach  the  base  of  the 
loess.  A  few  exposures  have  been  found  within  the  limits  of  the  lowan 
till,  but  such  exposures  are  far  less  common  than  beneath  the  lowan  loess. 

Several  excellent  exposures  of  the  Sangamon  soil  have  been  made  by 
railway  companies  at  points  where  the  overlying  loess  has  been  stripped 
off  to  obtain  a  filling  for  the  railway  track.  For  example,  along  the  Van- 
dalia  Railway,  a  few  miles  west  of  Marshall,  in  Clark  County,  Illinois,  an 
area  of  more  than  an  acre  has  been  stripped  of  the  loess,  leaving  the  black 
mucky  Sangamon  soil  at  the  base.  A  similar  exposure,  though  less  exten- 
sive, is  found  at  West  Point,  Iowa.  The  presence  of  the  black  muck 
here  seems  somewhat  remarkable,  inasmuch  as  it  occupies  the  crest  of  the 
marginal  ridge  of  the  Illinoian  drift.  The  upper  6  or  8  inches  is  a  deep- 
black  color,  beneath  which  there  is  a  deposit  of  gray  gumbo  2  or  3  feet  in 
thickness,  capping  the  Illinoian  till.  Extensive  exposures  of  black  muck 
below  the  loess  have  been  made  by  the  Chicago,  Burlington  and  Northern 
Railway  at  the  crossing  of  Johnson  Creek,  about  4  miles  south  of  Mount 

MON  XXXVIIl 9 


130  THE  ILLIISOIS  GLACIAL  LOBE. 

Carroll,  Illinois.  At  this  place  the  loess  has  a  thickness  of  nearly  20  feet. 
The  till  beneath  this  buried  soil  has  been  leached  as  far  down  as  exposures 
extend,  3  to  4  feet.  Still  another  extensive  exposure  of  the  soil  is  found  in 
the  pit  of  the  Brick  and  Tile  Works  at  Galva,  Illinois.  The  loess,  to  a 
depth  of  15  feet,  is  used  in  the  manufacture  of  the  brick  and  tile,  beneath 
which  is  a  black  mucky  soil  about  1  foot  in  depth,  which  caps  the  Illinoian 
till  sheet.  In  this  soil  a  log  about  1  foot  in  diameter  and  several  feet  in 
length  was  found  embedded. 

The  conditions  for  erosion  during  the  Sangamon  interglacial  stage  seem 
to  have  been  decidedly  less  favorable  than  in  the  Yarmouth  stage.  The 
streams  apparently  were  so  broad  and  sluggish  as  to  cut  only  shallow  val- 
leys, and  these  are  seldom  sharply  outlined.  The  general  absence  of 
well-defined  valleys  beneath  the  lowan  loess  on  the  area  occupied  by  the 
Illinoian  drift  sheet,  when  taken  in  connection  with  their  conspicuousness 
in  the  Kansan  drift,  is  liable  to  give  the  impression  that  only  a  brief  inter- 
val separates  the  Illinoian  from  the  lowan  glacial  stage.  But  if  interpreta- 
tions are  made  from  the  leaching,  and  depth  of  peat  and  muck  accumulation 
during  the  Sangamon  interglacial  stage,  there  are  found  indications  of  a 
period  which  compares  favorably  in  length  with  the  Yarmouth  interglacial 
stage.  The  depth  and  degree  of  oxidation  of  the  Illinoian,  when  compared 
with  the  lowan,  are  also  impressive  evidence  in  favor  of  a  wide  separation 
in  the  dates  of  deposition  of  the  two  deposits.  The  amount  of  erosion, 
therefore,  appears  to  be  a  poor  index  of  the  length  of  the  interglacial  period, 
though  if  low  altitude  and  slack  drainage  be  assumed  it  easily  harmonizes 
with  the  evidence  of  a  long  interval  denoted  by  the  other  features  of  the 
drift.  In  discussing  this  matter  with  the  several  glacialists  who  are  familiar 
with  the  deposits  representative  of  each  glacial  stage  the  writer  finds  them 
unanimous  in  considering  the  Illinoian  drift  a  much  older  deposit  than  the 
lowan.  There  is  some  difference  of  opinion  as  to  whether  the  Sangamon 
or  the  Yarmouth  is  the  longer  interglacial  interval.  The  wx'iter  inclines  to 
the  opinion  that  the  Yarmouth  is  the  longer  interval. 


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CHAPTER   VII. 
THE  lOWAN  DRIFT  SHEET  AND  ASSOCIATED  DEPOSITS. 

THE  lOWAN  SHEET  OF  THE  ILLIKOIS  LOBE. 

The  sheet  of  drift  to  which  the  name  lowan  is  here  appHed  is  referred 
to  the  lowan  stage  of  glaciation,  not  because  of  direct  connection  with  the 
lowan  drift  of  eastern  Iowa,  but  because  of  an  apparent  similarity  with  the 
lowan  drift  of  eastern  Iowa  in  its  connection  with  the  great  sheet  of  loess 
in  the  Mississippi  Basin.  As  shown  below,  the  loess  overlaps  this  di-ift  sheet 
only  a  short  distance,  and  was  deposited  apparently  while  the  ice  sheet  was 
melting  away,  there  being  no  clear  evidence  of  an  exposiu'e  of  its  till  to 
pi'otracted  atmospheric  action  prior  to  the  deposition  of  the  loess. 

DISTRIBUTION. 

The  lowan  sheet  of  the  Illinois  lobe  was  formed  by  a  southwestward 
ice  movement  over  northern  Illinois.  Its  western  border  has  been  traced 
in  some  detail  by  Mr.  Oscar  Hershey,  through  Wiimebago,  Ogle,  Lee,  and 
Whiteside  counties.  The  writer  had  previously  noted  the  occurrence  of 
this  drift  in  Winnebago,  Ogle,  and  Lee  counties,  but  had  not  attempted  a 
precise  mapping  of  its  western  border. 

The  border  is  found  to  enter  Illinois  from  Wisconsin  at  the  valley  of 
Sugar  River,  about  12  miles  west  of  Beloit.  It  follows  this  valley  south- 
ward to  the  Pecatonica  Valley  and  thence,  as  shown  in  PL  XII,  passes  up 
the  Pecatonica  about  to  the  line  of  Winnebag'O  and  Stephenson  counties, 
where  it  crosses  to  the  south  side  of  the  river  and  returns  eastward  to  the 
city  of  Rockford,  thus  forming  a  narrow  lobe  at  the  Pecatonica  Basin,  hav- 
ing a  protrusion  of  about  12  miles  and  a  width  no  greater  than  its  length. 
This  lobe  is  called  the  Pecatonica  lobe,  since  it  occupies  a  low  district  or 
basin  drained  by  the  Pecatonica  River. 

■^  131 


132  THE  ILLINOIS  GLACIAL  LOBE.  .   ' 

Below  Rockford  the  border  is  found  to  follow  nearly  the  course  of 
Rock  River  to  the  vicinity  of  Oregon.  Here  Hershey  makes  a  division  of 
the  drift  margin.  The  outer  margin  passes  westward  to  Polo.  The  inner 
margin  passes  southward  along  or  near  Rock  River  to  the  vicinity  of  Dixon. 
It  there  crosses  the  river  in  a  westward  course  and  follows  the  north  border 
of  a  lowland  tract  which  extends  a  few  miles  back  from  Rock  River.  North 
of  Sterling  it  joins  the  outer  margin.  Hershey's  tracing  of  the  outer  margin 
was  carried  no  farther  than  Polo,  but  the  writer  has  examined  the  district 
south  and  west  from  Polo,  and  also  the  portion  of  this  margin  from  Polo 
eastward  to  Rock  River. 

Eastward  from  Polo  there  is  a  definite  border,  characterized  by  low 
swells  of  till,  among  which  are  saucer-like  depressions,  giving  the  surface  a 
nmch  fresher  appearance  than  that  of  the  older  sheet  which  occupies  the 
district  to  the  north  and  west.  At  Polo  the  margin  appears  to  swing  south- 
ward and  follow  the  east  border  of  the  Elkhorn  Creek  Basin  into  Whiteside 
County.  The  border  is  not  so  definite  here,  however,  as  east  of  Polo,  there 
being  only  a  few  till  swells  and  occasional  basins  in  the  outer  part  of  the 
drift  sheet.  This  line  connects  in  eastern  Whiteside  County,  about  5  miles 
northeast  of  Sterling,  with  the  inner  margin  traced  by  Plershey.  Hershey's 
chief  criterion  in  mapping  the  inner  border  is  a  change  in  the  character  of 
the  till,  such  as  characterizes  the  margin  farther  north,  that  to  the  east  of  it 
being  more  sandy  than  that  to  the  west  and  displaying  a  pink  tint  not  noted 
to  the  west.  The  portion  between  the  inner  and  outer  margins  has  a  more 
compact  texture  than  the  remainder  of  the  lowan  drift  sheet.  The  cause 
for  this  difference  is  not  yet  apparent. 

The  margin  lies  north  of  Rock  River  at  least  as  far  west  as  Rock  Island 
Junction.  There  is  a  small  area  on  the  north  side  of  Rock  River,  west  from 
Rock  Island  Junction,  in  which  a  sheet  of  drift  with  fresher  aspect  than  the 
Illinoian  is  found.  It  is  apparently  confined  to  a  lowland  tract  whose  north 
border  is  followed  approximately  by  the  Chicago  and  Northwestern  Rail- 
road from  Round  Grove  to  Morrison,  and  whose  west  border  lies  along  Rock 
Creek  from  Morrison  south  to  the  valley  of  Rock  River.  To  the  north  and 
west  of  this  lowland  there  is  a  heavy  deposit  of  loess  which  largely  con- 
ceals the  underlying  deposits,  but  the  lowland  has  only  a  thin  coating  of 
loess  except  in  a  few  ridges  resembling  the  paha  of  eastern  Iowa.  Such  an 
extension  of  the  lobe  as  would  be  necessary  to  carry  it  to  Morrison  seems 


THE  lOWAN  DRIFT  SHEET.  133 

rather  questionable,  especially  since  it  calls  for  a  movement  north  of  west. 
It  is,  however,  not  so  narrow  a  tong-ue  as  appears  to  have  been  thrust  west- 
ward into  the  Pecatonica  Basin,  and  projects  but  4  or  6  miles  beyond  a  regu- 
lar border  in  line  with  that  in  eastern  Whiteside  County.  The  difficulties 
seem  scarcely  as  great  as  would  be  involved  in  an  invasion  of  ice  from 
eastern  Iowa  into  this  district  at  the  lowan  stage  of  glaciation.  There  are, 
however,  in  northwestern  Whiteside  and  southwestern  Carroll  counties 
features  which  raise  the  suspicion  that  ice  from  the  Iowa  side  may  have 
crossed  into  that  district  in  the  lowan  stage  of  glaciation  and  extended  as 
far  east  as  the  meridian  of  Morrison.  It  becomes  necessary,  therefore,  to 
consider  the  question  of  an  extension  of  the  lowan  ice  sheet  from  Iowa 
southeastward  into  this  tract.     This  question  is  considered  later  (p.  144). 

It  is  difficult  to  determine  the  position  of  the  border  of  this  ice  sheet 
south  from  Rock  River,  since  there  is  a  broad  area  occupying  the  interval 
between  Rock  and  Green  rivers,  in  which  heavy  deposits  of  sand  occur. 
Exposures  of  fresh-looking  till  north  of  Spring  Hill  seem  to  be  of  lowan 
age.  South  from  the  Glreen  River  sand  deposits  there  is  a  narrow  tract  of 
low  country  extending  eastward  from  Geneseo  to  the  vicinity  of  Sheffield, 
in  which  there  is  very  little  sand,  and  also  very  little  loess  compared  with 
the  covering  on  the  higher  districts  to  the  south,  and  which  may  prove  to 
have  been  occupied  by  the  Illinois  lobe  of  the  lowan  ice  sheet  during  the 
loess  deposition.  Its  south  border  is  within  2  or  3  miles  south  of  the  Chi- 
cago, Rock  Island  and  Pacific  Railway  throughout  the  interval  between 
Geneseo  and  Sheffield,  and  is  marked  by  a  bluft-like  rise  of  40  to  60  feet  to 
a  belt  of  heavy  loess.  Immediatel}^  east  of  Sheffield  the  outer  moraine  of 
the  Wisconsin  drift  sets  in,  and  no  drift  attributable  to  the  lowan  invasion  has 
been  recognized  outside  its  limits  in  districts  to  the  south.  There  appears, 
therefore,  to  be  striking  similarity  between  this  lobe  of  lowan  age  and  that 
which  occupied  eastern  Iowa.  They  each  show  at  the  north  remarkable  pro- 
trusions, extending  in  both  cases  nearly  to  the  borders  of  the  Driftless  Area. 
Their  margins  also  are  strikingly  different  in  outline  from  those  of  preceding 
and  succeeding  sheets  in  the  same  districts.  The  east  lowan  sheet  has  been 
found  to  extend  only  about  to  the  latitude  of  Rock  Island  and  Muscatine, 
and  possibly  the  lobe  which  we  are  considering  extended  no  farther  south. 
There  are,  however,  till  deposits  in  eastern  Illinois,  as  far  south  as  Iroquois 
County,  which  are  suspected  to  be  of  lowan  age,  as  indicated  below. 


134  THE  ILLINOIS  GLACIAL  LOBE. 

TOPOGRAPHIC  EXPRESSION. 

At  several  places  along  the  border  of  this  drift  sheet  in  Winnebago,  Ogle, 
and  Whiteside  counties  low  swells  and  ridges  appear,  but  they  are  seldom 
more  than  10  or  15  feet  in  height.  These  serve,  however,  to  give  definite- 
ness  to  the  margin,  although  they  are  very  inconspicuous  features.  In  most 
cases  the  low  swells' are  plainly  independent  of  drainage  erosion,  there  being 
instances  in  which  they  pass  across  a  valley  which  had  been  formed  in  the 
earlier  drift,  dotting  its  slopes  and  bottoms  and  passing  onward  over  the 
bordering  uplands  in  utter  disregard  of  the  drainage  lines.  Such  knolls 
may  be  seen  near  the  mouth  of  Leaf  River  in  Ogle  County,  and  also  on  the 
borders  of  the  Pecatonica  in  Winnebago  County.  Along  portions  of  the 
border  the  separation  of  the  erosion  features  from  the  drift  aggregations 
produced  by  this  ice  invasion  is  somewhat  difficult.  Such  is  the  case  on  the 
borders  of  the  lowland  tract  north  and  west  from  Sterling,  where  the  imdu- 
lations  are  probably  in  part  due  to  drainage  erosion.  A  similar  difficulty 
is  experienced  in  the  narrow  belt  of  lowland  east  from  Greneseo.  There  are 
present,  however,  in  both  these  districts  knolls  and  ridges  of  drift  which 
appear  to  be  independent  of  drainage  erosion  and  referable  to  the  inequali- 
ties of  deposition  of  the  ice. 

No  paha  have  been  found  in  Illinois  except  in  western  Whiteside  and 
northwestern  Henry  counties  in  the  districts  in  which  some  uncertainty  is 
felt  concerning  the  occupancy  by  ice  at  this  stage  of  glaciation.  The  paha 
are  scattered  over  the  portion  of  Whiteside  County  north  of  Rock  River 
from  Round  Grove  westward  to  the  borders  of  the  Mississippi,  but  are  best 
developed  on  the  lowland  tract  south  and  east  from  Morrison  and  on  the  till 
tract  between  Rock  and  Green  rivers,  which  leads  from  Spring  Hill  south- 
westward  to  the  mouth  of  Green  River.  They  are  straight  ridges,  usually 
a  mile  or  less  in  length,  but  occasionally  reaching  2  miles.  They  are  often 
sharp  crested,  with  a  width  of  scarcely  50  feet  at  top,  and  present  abrupt 
slopes.  Occasionally  they  reach  a  Avidth  of  40  or  50  rods,  including  slopes. 
In  height  they  range  from  10  feet  or  less  up  to  about  50  feet.  The  trend  is 
quite  uniformly  about  WNW.-ESE.  Several  of  them  may  be  seen  in  the 
Clinton  topographic  sheet,  PI.  XVIII  (in  pocket).  The  longest  paha  noted 
is  found  about  4  miles  south  of  Morrison,  and  leads  from  the  center  of  sec.  4 
west-northwest  to  the  noi-th  line  of  sec.  6,  T.  20,  R.  5  E.,  a  distance  of  about 


THE  lOWAN  DRIFT  SHEET.  135 

2  miles.     It  is  interrupted  by  a  narrow  break  in  the  west  part  of  sec.  4, 
through  which  a  small  stream  passes.     This  paha  is  30  to  45  feet  in  height 
and  40  or  50  rods  wide,  including  slopes.     It  presents  the  unusual  feature  of 
carrying  basins  on  its  slopes.     One  near  the  line  of  sees.  4  and  5  contains  a 
pond  with  an  area  of  about  one-half  acre.     Another  prominent  ridge,  appar- 
ently a  paha,  is  found  at  Round  Grove,  that  village  being  situated  near  its 
western  end.     The  ridge  is  about  1^  miles  long,  30  to  40  rods  wide,  and 
20  to  40  feet  high.     It  is  separated  by  only  a  narrow  sag,  scarcely  wider 
than  the  ridge,  from  an  upland  tract  on  the  north  which  stands  as  high  as 
its  crest,  and  it  may  possibly  be  only  a  detached  portion  of  that  upland. 
It  seems  difficult,  however,  to  account  for  a  stream  capable  of  causing  its 
separation  from  'ihe  upland,  and  that  interpretation  would  not  be  thought  of 
if  it  stood  like  the  paha  last  mentioned,  some  3  miles  from  the  upland. 
Just  north  of  the  village  of  Spring  Hill  there  is  a  paha  nearly  a  mile  in 
length  which  rises  about  20  feet  above  the  general  level  of  border  districts 
and  has  a  width  of   only  20  to  30  rods,  including  slopes.     Several  paha 
ridges  appear  on  the  low  upland  north  of  Green  River  in  northwestern 
Henrv  County.     The  most  prominent  ones  noted  are   a  group   of  three 
nearly  parallel  ridges  crossed  by  the  Geueseo  and  Sharon  wagon  road  3  or 
4  miles  north  of  Geneseo,  in  sec.  34,  T.  18,  R.  3  E.     Their  highest  points 
rise  40  to  45  feet  above  the  bordering  uplands,  and  they  are  each  nearly  a 
mile  in  length.     Shorter  ridges  of  about  the  same  height  occur  in  sees.  31 
and  32  of  the  same  township  and  in  sec.  4,  T.  17,  R.  2  E. 

There  are  in  eastern  Winnebago'  and  Boone  counties  till  ridges 
elongated  in  an  ENE.-WSW.  direction,  apparently  the  direction  of  ice 
movement,  which  are  drumlinoid  in  form.  These  ridges  have  been  exam- 
ined by  Mr.  I.  M.  Buell,  in  connection  with  his  study  of  the  drumlins  of 
eastern  Wisconsin,  and  he  considers  them  a  phase  of  drumhn  development, 
though  less  perfect  in  form  than  the  typical  drumlin.  These  ridges  usually 
have  a  length  of  a  mile  or  less  and  a  breadth  scarcely  half  as  great  as  their 
length.  The  higher  ones  rise  40  or  50  feet  above  border  districts,  but  the 
majority  are  30  feet  or  less  in  height.  With  these  drumlinoid  ridges  there 
are  associated  knolls  of  nearly  conical  form,  giving  the  surface  a  semi- 
morainic  aspect.  No  definite  morainic  belts,  however,  have  been  traced 
across  the  district  occupied  by  this  ice  sheet.  The  knolls  appear  in  isolated 
clusters  surrounded  by  plane-surtaced  tracts  of  greater  extent. 


136  THE  ILLINOIS  GLACIAL  LOBE. 

In  the  southeastern  part  of  Winnebago  County  and  in  the  portion  of 
Ogle  County  between  the  outer  moraine  of  the  Wisconsin  series  and  the 
present  valley  of  Rock  River,  and  also  in  southwestern  Boone  County, 
gravel  knolls  of  considerable  prominence  are  found.  These  in  most  cases 
appear  to  be  a  product  of  the  lowan  invasion,  for  the  gravel  has  a  freshness 
corresponding  to  that  of  the  lowan  till.  In  one  instance  (near  King's 
Station,  in  Ogle  County)  a  gravel  knoll,  opened  for  railway  ballast,  shows 
what  appears  to  be  a  more  aged  gravelly  deposit  at  the  base  than  that 
constituting  the  body  of  the  knoll.  It  had  a  height  of  45  feet  before  the 
excavation  was  made,  and  several  others  in  that  vicinity  are  equally  large, 
though  the  majority  are  20  feet  or  less.  A  chain  of  sharp  gravel  knolls  in 
southwestern  Boone  County,  near  Irene,  trends  north  to  south  and  has  a 
length  of  over  a  mile.  At  the  north  it  merges  into  a  till  ridge  with  gentle 
slope  and  with  a  smoother  contour  than  the  gravelly  belt.  This  ridge,  with 
the  gravelly  knolls,  is  probably  a  marginal  deposit  formed  at  a  shght  halt 
made  by  the  ice.  The  knolls  are  only  20  to  30  feet  high,  but  rise  promptly 
from  the  boi'dering  upland  plain.  Near  Stillman  Valley  a  few  esker-like 
ridges  of  gravel  are  developed  which  trend  northeast  to  southwest.  These 
are  closely  associated  with  gravelly  knolls,  and  the  longest  are  only  a  mile 
or  less  in  length.  An  esker-like  ridge  was  also  observed  by  Hershey  near 
Sterling,  Illinois. 

The  greater  part  of  the  surface  of  this  sheet  of  drift,  like  that  of  the 
lUinoian  sheet,  is  plane  or  but  very  gently  undulating  and  devoid  of 
notable  topographic  featvires.  The  principal  ridges  and  knolls  associated 
with  the  drift  sheet  are  represented  on  PI.  XII,  a  reference  to  Avhich  will 
serve  to  show  the  small  percentage  of  the  area  occupied  by  them. 

THICKNESS  OF  THE  DRIFT. 

In  eastern  Winnebago  and  northern  Boone  counties,  Avhere  the  drum- 
linoid  drift  ridges  and  associated  knolls  abound,  the  drift  of  lowan  age  is 
known  to  have  considerable  thickness,  possibl}'  an  average  of  40  feet  or 
more.  Aside  from  this  small  district,  the  drift  referable  to  the  lowan 
invasion  appears  to  form  generally  only  a  thin  and  somewhat  patchy 
deposit.  In  the  vicinity  of  the  Ijorder  the  drift  is  often  confined  to  the 
small  knolls,  ID  or   \h  feet  in   hei"lit,  tlic  low  oTound  anion"-  tlie  knolls 


THE  10 WAN  DEIFT  SHEET.  137 

being  immediately  miderlaiii  by  an  older  sheet  of  drift.  On  hillside  expo- 
sm-es  also,  some  distance  within  the  border,  it  has  been  fonnd  that  in  places 
a  thin  deposit  of  lowan  drift  occurs  at  the  tops  of  hills,  ^yhile  the  greater 
part  of  the  slope  exposes  Illinoian  drift.  In  not  a  few  places  in  the  midst 
of  the  lowan  drift  area  only  the  Illinoian  drift  is  fonnd  at  the  tops  of  the 
hills,  though  the  hills  were  apparently  covered  by  the  lowan  ice  sheet. 
There  is  apparently  a  smaller  amount  of  loess  associated  with  this  ice  lobe 
than  Avith  the  lowan  of  eastern  Iowa.  The  districts  immediately  outside 
its  border  have  only  a  thin  coating,  5  or  10  feet,  while  the  thickness  of  the 
loess  within  its  bordei's  is  even  smaller  in  amount.  It  Avould  seem  a  liberal 
estimate  to  allow  an  average  of  10  feet  of  both  till  and  loess  as  the  product 
of  the  lowan  invasion  in  Illinois.  It  is  therefore  sufficient  to  modify  but 
little  the  features  of  the  country  which  it  occupies. 

STRUCTURE  OF  THE  DRIFT. 

The  drift  of  the  lowan  invasion  has  generally  a  more  sand}^  constitu- 
tion than  that  of  the  Illinoian  which  underlies  it.  Along-  the  was'on  roads 
and  in  other  situations  where  it  has  been  exposed  to  the  action  of  slight 
wash,  it  frequently  presents  the  appearance  of  fine  sand,  where  the  Illinoian 
drift  would  present  the  appearance  of  clay.  Not  infrequently  the  matrix 
appears  to  be  nearly  free  from  clayey  material.  There  are  other  places, 
however,  where  the  till  has  a  stiff  clayey  matrix,  but  is  readily  distinguish- 
able from  the  Illinoian  by  its  fresher  surface  Associated  as  this  till  sheet 
is  with  the  loess,  the  latter  being  apparently  a  derivation  from  the  former, 
a  sandy  till  is  a  natural  product,  the  fine  material  being  carried  into  the 
loess.  This  difference  in  the  two  tills  greatly  affects  the  character  of  the 
soils.  Where  the  lowan  drift  is  present  a  dark  soil  is  usually  developed, 
while  in  the  outlying  districts  of  northwestern  Illinois  the  soil  is  of  a  yellow 
or  brown  color. 

In  places  the  lowan  till  is  covered  to  a  depth  of  several  feet  by  loess, 
but  in  the  Pecatonica  Basin  and  much  of  the  country  east  of  Rock  River 
the  loess  amounts  to  scarcely  more  than  a  skim  coating  1  or  2  feet  in  depth, 
a  coating  such  as  may  have  been  deposited  by  wind  action  since  the  final 
withdrawal  of  the  ice  sheet  or  have  accompanied  the  melting  of  the  ice.  The 
portions  best  protected  by  loess  present  a  till  scarcely  at  all  stained  or 


138  THE  ILLINOIS  GLACIAL  LOBE. 

leached  by  atmospheric  action,  a  feature  which  seems  to  indicate  that  the 
deposition  of  the  loess  closely  followed  the  withdrawal  of  the  ice. 

Within  the  limits  of  the  Pecatonica  lobe  there  is  a  very  sandy  till 
liberally  set  with  small  fragments  of  limestone  and  usually  leached  to  a 
depth  of  2  to  4  feet.  East  from  Rock  River,  in  Winnebago  and  Boone 
counties,  the  till  is,  on  the  whole,  less  sandy  than  west  of  that  stream. 
Several  exposures  were  noted  in  railway  cuttings  between  Roscoe  and 
Caledonia  in  which  the  till  becomes  calcareous  at  a  depth  of  but  1^  to  2 
feet,  but  there  is  usually  leaching  to  a  depth  of  3  feet  or  more. 

Exposures  of  lowan  till  were  noted  by  the  writer  on  the  south  and 
east  borders  of  the  city  of  Dixon.  One  on  Second  street  and  Dumont  ave- 
nue shows  a  thin  sandy  capping,  beneath  which  is  fresh-looking  calcareous 
till.  Farther  east  the  sand  disappears,  yet  the  till  is  found  to  have  suffered 
leaching  only  to  a  depth  of  3  or  4  feet  and  is  markedly  fresher  than  the 
Illinoian.  In  the  south  part  of  Dixon,  along  the  Chicago  and  Northwestern 
Railway,  the  first  cutting  east  of  the  crossing  of  the  Illinois  Central  Rail- 
road shows  a  calcareous  sand,  apparently  lowan,  resting  on  a  leached  till 
in  which  no  effervescence  with  acid  could  be  obtained  within  5  or  6  feet  of 
top.  In  exposures  farther  east  a  thin  capping  of  loess  rests  directly  on  the 
Illinoian  till.  There  appears,  therefore,  to  be  only  a  patchy  deposit  of 
lowan  drift  in  the  vicinity  of  this  city.  Hershey  has  noted  several  expo- 
sures of  the  lowan  between  Dixon  and  Sterling,  and  west  from  there  to 
Rock  Island  Junction.  The  common  phase  is  a  very  sandy  till,  in  places 
becoming  clear  sand. 

In  railway  cuttings  east  from  Polo  low  knolls  belonging  to  the  lowan 
drift  have  been  well  exposed.  They  are  capped  by  about  4  feet  of  loess- 
like silt,  beneath  which  the  till  is  found  to  be  calcareous  from  top  to  bottom. 
It  is  more  clayey  than  in  exposures  near  Dixon  and  Sterling.  In  this 
locality  the  lowan  drift  appears  to  be  restricted  mainly  to  the  knolls,  for 
exposures  of  the  llliiioian  drift  appear  in  ditches  made  by  the  railway  in 
crossing  the  low  tracts  among  the  knolls.  At  the  village  of  Stratford,  5 
miles  east  of  Polo,  the  railway  exposes  a  bed  of  fossiliferous  silt  at  the 
base  of  the  lowan  drift,  resting  on  an  old  land  surface  formed  on  the 
Illinoian.  The  fossils  appear  to  be  entirely  of  one  species  (Succinea  avara). 
In  two  other  localities  fossiliferous  silts  have  been  found  at  the  base  of  the 
lowan,  one  being  in  the  railway  cuttings  on  the  Illinois  Central  immediately 
west  of  Irene,  in  southwestern   Boone  County,  ;nid  another  in  the  railway 


THE  lOWAK  DRIFT  SEIEET.  13^ 

cuttings  on  the  Chicago  and  Northwestern,  1  mile  east  of  Belvidere.     Here, 
as  at  Stratford,  the  fossils  are  mainly  of  one  species  (^Succinea  avara). 

The  pebbles  and  smaller  rock  constituents  of  the  till  appear  to  be 
largely  limestone  whose  native  ledges  are  distant  but  a  few  miles  to  the  east 
and  north.  In  this  respect  it  conforms  to  the  structure  of  the  underlying 
lUinoian  sheet,  and  it  seems  not  improbable  that  it  has  obtained  much  of 
the  material  from  the  lUinoian.  There  is  not  found  between  the  lowan  and 
Illinoian  till  sheets  of  the  Illinois  lobe  such  a  striking  contrast  in  rock 
constituents  as  is  reported  by  McGee  and  by  Calvin  to  be  found  in  the 
lowan  and  Kansan  of  northeastern  Iowa.  The  lowan  is  reported  by  Calvin 
to  carry  scarcely  any  pebbles  or  lai-ge  rock  fragments  of  local  deiivation, 
while  the  underlying  Kansan  is  thickly  set  with  them. 

The  paha  ridges  of  western  Whiteside  and  northeastern  Henry  coun- 
ties'usually  contain  a  peculiar  phase  of  loess.  The  basal  portion  is  a  fine 
sand,  rather  than  loess,  in  which  many  of  the  individual  grains  may  be  seen 
by  the  naked  eye,  though  with  some  difficulty.  The  great  majority  of 
grains  of  ordinary  loess  are  much  too  fine  to  be  seen  with  the  naked  eye. 
From  Round  Grove  the  fine  sand  at  the  base  of  the  paha  ridge  has  been 
shipped  to  Chicago  foundries  for  use  as  a  molding  sand. 

In  some  cases  the  upper  portion  of  the  paha  assumes  a  sandy  consti- 
tution. As  a  rule,  however,  it  consists  of  a  loess  similar  to  the  bluff  loess 
of  the  main  waterways,  and  its  banks  will  stand  in  vertical  walls  for  j^ears. 
Like  the  bluff  loess,  it  is  fossiliferous,  but  as  yet,  so  far  as  the  writer  is 
aware,  no  determination  of  the  species  of  fossils  represented  has  been  made. 
Before  leaving  this  subject  a  few  sections  are  presented  from  the  debatable 
district  in  central  and  southern  Whiteside  County,  which  serve  to  show  the 
freshness  of  the  till  and  the  occurrence  of  more  than  one  drift  sheet. 

A  well  made  for  Mrs.  Seeley  on  the  slope  of  the  Round  Grove  Ridge, 
at  a  level  about  10  feet  from  the  basg,  is  reported  by  the  driller  to  have 
penetrated  the  following  beds  : 

Section  of -well  of  Mrs.  Seeley  at  Bound  Grove,  Illinois. 

Feet. 

Earthy  soil  and  subsoil 3 

Fiue  yellow  sand 5 

Yellow  clay,  no  pebbiec:  noted 5 

Sol't  blue  pebbly  clay  (pro'oably  lowan  till) S 

Black  dirt  with  wood  embedded  (probably  Sangamon) 2 

Till  mainly  of  blue- gray  color  (probably  Illinoian) 17 

Limestone. 


140  THE  ILLINOIS  GLACIAL  LOBE. 

Tlie  reference  of  tlie  soft  blue  clay  of  tliis  section  to  the  lowan  is 
apparently  supported  by  an  exposure  a  short  distance  west  of  Round  Grove, 
where  the  excavations  at  the  side  of  the  railway  show  a  soft  till  wliich, 
though  yellow  at  top,  assumes  a  blue  color  within  3  or  4  feet  of  the  surface. 
It  has  an  appearance  as  fresh  as  any  exposure  of  lowan  till  noted  in 
districts  to  the  east.  The  exposure  is  not  sufficiently  deep,  however,  to 
show  the  depth  of  this  till  or  to  enable  one  to  determine  whether  an  older 
sheet  underlies  it.  Directly  east  of  Round  Grove  about  1^  miles,  the  loess 
is  found  to  rest  upon  a  till  having-  leached  and  reddened  sui-face,  evidently 
as  old  as  the  Illinoian.  These  features  indicate  either  that  the  lowan  ice 
failed  to  cover  the  district  immediately  east  of  Round  Grove  or  that  it  did 
not  form  a  continuous  sheet  of  till.  The  first  interpretation  seemed  to  the 
writer  at  one  time  the  more  probable,  but  further  reflection  and  considera- 
tion of  the  fact  that  this  drift  sheet  is  somewhat  patchy  in  the  districts  to 
the  northeast  has  led  to  a  more  favorable  view  of  the  second  interpretation. 
If  the  fresh-looking  drift  found  west  of  Round  Grove  is  of  lowan  age,  the 
district  to  the  east  of  that  village  was  probably  covered  by  that  ice  lobe. 

West  and  south  of  Morrison,  on  the  borders  of  Rock  Creek  and  east- 
ward from  its  valley,  sandy  till  of  fresher  appearance  than  the  Illinoian  was 
noted  at  several  points.  In  some  cases  it  is  found  to  be  calcareous  within 
3  feet  of  the  surface.  At  the  point  where  the  wagon  road  ascends  from 
Rock  River  Valley  toward  Spring  Hill  an  exposui"e  was  found  in  which  the 
loess  rests  directly  upon  an  unleached  surface.  It  seems  scarcely  probable 
that  there  had  been  erosion  of  the  till  prior  to  the  loess  deposition,  for  the 
till  .surface  there  rises  to  its  usual  elevation  in  that  locality.  In  the  cases 
above  noted  also  no  evidence  was  found  of  any  removal  of  the  surface  por- 
tion of  the  till.  Exposures  of  till  are  rare  in  this  region,  partly  because  of 
the  shallow  depth  of  valleys  and  partly  because  of  concealment  by  loess. 
The  few  above  noted  comprise  alL  that  were  observed  by  the  writer  in 
central  and  southern  Whiteside  County. 

STRI/E. 

A  few  exposures  of  stritie  have  been  found  in  Winnebago  and  Ogle 
counties  which  fall  within  the  limits  of  the  lowan  drift  sheet,  but  which  are 
not  referred  positively  to  that  ice  invasion,  since  they  may  be  referable  to 


lOWAN  DllIFT  SFIEET  AND  ASSOCIATED  DEPOSITS.  141 

the  Illinoian.  These  have  all  been  observed  by  Buell,  who  has  kindly 
furnished  a  list  of  the  localities  and  bearings  for  publication.  They  appear 
in  the  list  on  page  88. 

PROBABLE  EXTEZSTT  OP  lOWAN   DRIFT  SHEET  BENEATH  THE 

WISCOKSIN. 

The  extent  of  the  lowan  drift  beneath  the  Wisconsin  can  be  deter- 
mined only  approximately,  and  chiefly  by  inferential  reasoning.  An  infer- 
ential determination  may  be  based  upon  the  occurrence  of  a  series  of  drift 
sheets  sufficiently  full  to  include  the  lowan.  For  example,  if  there  is  but 
one  older  sheet  of  drift  near  the  southern  or  western  border  of  the  Wiscon- 
sin, and  if  upon  passing  back  beneath  the  Wisconsin  two  distinct  sheets  of 
older  drift  are  found,  it  may  be  inferred  that  the  additional  sheet  is  either 
the  lowan  or  is  a  sheet  still  older  than  the  Illinoian.  A  series  of  well  sections 
have  made  it  evident  that  there  are  three  well-defined  drift  sheets  in  the 
northern  portion  of  eastern  Illinois,  two  of  which  are  older  than  the  Wis- 
consin. It  may  be  difficult  to  determine  whether  the  additional  sheet  is  of 
lowan  or  pre-Illinoian  ag-e,  since  the  data  are  based  almost  entirely  upon 
well  sections,  and  the  material  thus  obtained  is  scarcely  adequate  for  a 
satisfactory  determination.  The  complicated  series  extends  as  far  south  as 
southern  Iroquois  County,  and  may  possibly  extend  into  Vermilion  and 
Champaign  counties,  though  the  sections  obtained  in  those  counties  do  not 
furnish  such  decisive  evidence  of  the  triple  series  as  is  found  in  Iroquois 
County. 

The  Wisconsin  drift  may  usually  be  readily  separated  from  the  older 
sheets  which  underlie  it.  Its  uniform  blue  color  and  the  ease  with  which  it 
may  be  penetrated  by  auger  or  spade  enables  the  well  drillers  to  distinguish 
it  readily  from  the  underlying  deposits,  which  are  of  brown  or  g'ray  color 
and  more  difficult  to  penetrate.  There  is  also  in  many  places  a  black  soil 
at  the  junction  of  this  sheet  with  the  underlying  drift  which  furnishes  addi- 
tional evidence  of  the  passage  from  the  Wisconsin  to  an  older  drift.  The 
well  records  obtained  in  the  flowing  well  district  of  southern  Iroquois 
County  have  brought  to  light  the  occurrence  of  a  second  soil  at  a  horizon 
25  to  50  feet  or  more  lower  than  the  base  of  the  Wisconsin  drift.  There  is 
often  considerable  peat  at  this  lower  soil  horizon,  and  with  it  a  large 
amount  of  water-bearing  sand  from  which  the  flowing  wells  are  obtained. 


142  THE  ILLINOIS  GLACIAL  LOBE. 

The  peat  in  one  instance  is  found  to.  have  a  thickness  of  30  feet  (in  a  well 
on  Dr.  Ludden's  farm,  5  miles  south  of  Clayton),  and  not  infrequently  has 
a  thickness  of  5  or  10  feet.  Few  wells  have  been  sunk  below  this  lower 
soil  horizon,  but  these  indicate  that  the  di'ift  may  extend  in  places  to  a  con- 
siderable depth.  In  several  cases,  however,  the  bottom  of  the  di-ift  was 
reached  within  20  or  30  feet  below  the  lower  soil.  Both  sheets  of  drift 
beneath  the  Wisconsin  are  described  to  be  of  a  brown  or  brownish-g-rav 
color,  and  the  writer  was  unable  to  learn  of  any  distinguishing  character- 
istics. They  are  each  described  to  be  harder  to  penetrate  than  the  overly- 
ing Wisconsin  drift.  In  its  sm-face  exposures  the  lowan  is  usuallv  more 
easily  penetrated  by  a  spade  or  auger  than  the  Illinoian,  and  this  fact  may 
seem  to  favor  the  view  that  the  two  sheets  beneath  the  Wisconsin  in  Iro- 
quois County  are  Illinoian  and  pre-Illinoian  rather  than  lowan  and  Illinoian. 
However,  the  information  is  so  meager  and  the  character  of  the  observa- 
tions so  imperfect  that  it  can  scarcely  be  decided  from  these  records 
whether  the  middle  sheet  is  lowan  or  Illinoian.  The  following  data  con- 
cerning the  three  sheets  in  Iroquois  County  will  serve  to  set  forth  their 
relative  thickness: 

Clayton  and  vicinity. 

Feet. 

Upper  or  Wiscousiu  drift  sheet 60  or  70 

Middle  drift  slieet 30  or  35 

Lower  drift  sheet 45-|- 

Ash  Grove  timber  belt. 

Upper  or  Wisconsin  drift 55  or  60 

Middle  drift  sheet 30  or  40 

Lower  drift  sheet 50-f- 

Grescent  City  and  vicinity. 

Feet. 

Upper  or  Wisconsin  drift  sheet 60 

Middle  drift  sheet 1.5  or  20 

Lower  drift  sheet 70-f- 

'  Onarga  and  vicinity. 

Feet. 

Upper  or  Wisconsin  drift  sheet 50  or  60 

Middle  drift  sheet 30  or  more 

L'ower  drift  sheet 175i 

Oilman  and  vicinity. 

Foet. 

Upper  or  Wisconsin  drift  sheet 75 

Middle  and  lower  drift  sheets 120 J; 


low  AN  DEIFT  SHEET  AND  ASSOCIATED  DEPOSITS.  143 

Milford  and  vicinity. 

Feet. 

Upper  or  Wisconsin  drift  sheet .  ..• 50 j^ 

Middle  drift  sheet 40  or  50 

Lower  drift  sheet 25 

Donovan  and  vicinity. 

Feet. 

Upper  or  Wisconsin  drift  sheeit - 100  J^ 

Middle  drift  sheet 40 

Lower  drift  sheet 30 

In  counties  farther  north  a  series  is  found  similar  to  that  displayed  in 
Iroquois  County.  It  is  best  shown  in  localities  where  the  drift  is  very 
thick,  as  is  the  case  in  much  of  Kane,  Uekalb,  and  McHenry  counties. 
As  these  counties  are  adjacent  to  the  exposed  portion  of  the  lowan  drift 
sheet  and  equally  far  to  the  north,  there  is  scarcely  a  doubt  that  the  middle 
sheet  should  be  referred  to  the  lowan.  Numerous  sections  of  wells  in 
these  counties  are  presented  in  the  portion  of  this  report  dealing  with  the 
wells  of  Illinois  (Chapter  XIV),  together  with  a  discussion  of  the  probable 
age  of  the  sheets,  where  more  than  one  was  penetrated.  From  these  it  may 
be  seen  that  the  Middle  or  lowan  drift,  as  in  the  exposed  portion,  is  much 
thinner  than  the  Wisconsin  and  has  a  depth  about  the  same  as  the  middle 
sheet  in  Iroquois  County.  These  points  of  resemblance,  although  not 
demonstrative  of  contemporaneity,  at  least  suggest  the  possibility  that  the 
lowan  drift  extends  into  Iroquois  County. 

A  loess-like  silt,  as  shown  below,  covers  the  Illinoian  di-ift  of  southern 
Illinois  outside  the  limits  of  the  Wisconsin  and  is  traceable  northward 
several  miles  beneath  the  Wisconsin.  This  appears  to  be  a  deposit  of 
lowan  age  like  the  loess  of  western  Illinois,  and,  like  the  loess,  it  may  be 
derived  from  the  ice  sheet.  Its  presence  in  southeastern  Illinois  and  also 
in  districts  farther  east,  for  it  is  found  as  far  east  as  central  Ohio,  is  thought 
to  bring  strong  support  to  the  view  that  the  ice  sheet,  at  the  lowan  stage, 
did  not  fall  short  many  miles  of  reaching  the  line  occupied  at  a  later  date 
by  the  Wisconsin  ice  invasion.  This  silty  outwash  is  of  sufficient  volume 
to  mantle  the  region,  as  far  south  as  the  Ohio  River,  with  a  deposit  having 
an  average  depth  of  probably  5  feet.  The  volume  of  this  deposit  would 
seem  to  indicate  that  the  southern  limits  of  the  ice  sheet  from  which  it  was 
derived  were  at  least  within  100  miles,  and  possibly  much  nearer,  the  south- 
ern limits  of  the  Wisconsin  drift  sheet,  not  only  in  Illinois,  but  in  Indiana 
and  Ohio. 


144  THE  ILLINOIS  GLACIAL  LOBE. 

PROBABLE  EXTENT  OF  THE  IOWA  PORTION  OP  lOWAN  DRIPT. 

InasniLicli  as  there  is  some  evidence  suggesting  a  slight  extension  of 
ice  from  Iowa  into  northwestern  Illinois  at  the  lowan  stage,  the  question 
of  the  extent  of  that  ice  sheet  is  liere  considered. 

The  "upper  till"  of  northeastern  Iowa  now  classed  largely  as  lowau 
di-ift  is  represented  by  McGree  to  have  its  eastern  border  near  the  western 
edge  of  the  Driftless  Area  from  the  Minnesota-Iowa  State  line  southeastward 
to  the  southern  point  of  the  Driftless  Area  near  Sabula,  lowa.^  Generally  it 
falls  short  a  few  miles  of  reaching  the  Driftless  Area,  but  in  southern  Jackson 
and  in  Clinton  County,  Iowa,  it  is  represented  to  extend  beyond  the  earlier 
sheet  and  to  constitute  the  border  of  the  Driftless  Area.  It  is  represented  to 
extend  to  the  Mississippi  Valley  from  northern  Clinton  County  southward 
to  Scott  County,  and  to  fall  short  but  a  few  miles  of  reaching  that  valley 
in  Scott  and  Muscatine  coimties.  A  tectonic  map^  represents  the  ice  sheet 
to  have  extended  across  the  Mississippi  and  rested  on  the  east  bluff  for  a 
few  miles  below  Clinton.  From  Muscatine  County  westward  the  limits  are 
not  definitely  given.  The  upper  till,  however,  is  represented  to  extend  to 
the  limits  of  the  district  reported  upon. 

The  investigations  carried  on  by  the  Iowa  survey  have  supported  the 
mapping  and  results  of  McGee  in  a  general  way,  but  not  in  all  details. 
Very  little  disagreement  as  to  the  boundary  is  found  from  the  Minnesota- 
Iowa  State  line  southward  to  Delaware  County,  Iowa.  But  from  that 
county  southward  to  eastern  Jones  County  Professor  Calvin,  of  the  Iowa 
survey,  places  the  limit  of  lowan  diift  a  few  miles  inside  McGee's  limit. 
There  are  certain  extramarginal  phenomena  recognized  in  the  disputed  ter- 
ritory which  he  considers  closely  related  to  the  lowan  invasion,  but  not 
requiring  the  presence  of  lowan  ice,  chief  among  which  are  heavy  accumu- 
lations of  loess  and  a  tendency  to  ridging  of  the  loess  in  lines  trending  from 
WNW.  to  ESE.,  as  in  the  undoubted  lowan  area. 

From  northern  Jones  Count}'  eastward  to  the  Mississippi  the  border 
has  not  yet  been  investigated  by  the  Iowa  survey,  but  the  writer  made 
some  examinations  in  this  district  in  1894  while  engaged  in  tracing  the  west 
border  of  the  Illinoian  drift.  '  The  examinations  were  begun  in  Clinton 
County  and  carried  westward.     On  the  uplands  northwest  of  Clinton  a  belt 


I  Eleventh  .\nii.  Kept.,  U.  S.  Geol.  Survey,  PI.  XLIV.  •'Op.  cit.,  PI.  LVI. 


EXTENT  OF  IOWA  PORTION  OF  lOWAN  DRIFT.  145 

of  thick  drift  was  discovered  along  which  rock  is  seldom  encountered  at 
less  than  80  feet,  and  in  places  the  drift  reaches  a  thickness  of  200  feet  or 
more.  This  thick  belt  of  drift  has  a  breadth  of  3  or  4  miles  and  at  first 
was  conjectured  to  be  the  marginal  ridge  of  the  Illiiioian  drift,  though  it  is 
somewhat  broader  than  the  general  width  of  that  ridge  in  southeastern  Iowa. 
It  carries  a  thick  capping  of  loess  (20  to  30  feet  or  more)  which  greatly 
obscures  the  glacial  deposits.  A  few  exposures  were  found,  however,  which 
showed  a  surface  reddening  and  leaching  of  the  till  such  as  is  displayed  in 
the  Illinoian  or  Kansan  sheets  of  drift.  Such  reddening  has  not  been  found 
in  loess-covered  portions  of  the  lowan  drift  in  northwestern  Illinois,  nor,  so 
far  as  the  writer  is  aware,  has  it  been  noted  in  the  lowan  drift  of  north- 
eastern Iowa.  These  observations  were  made  in  the  district  where  only  the 
upper  till  is  represented  on  McGee's  map.  The  Avriter,  therefore,  inferred 
that  the  upper  till  here  should  be  considered  Illinoian  and  proceeded  west- 
ward, expecting  to  find  the  belt  of  thick  drift  swing  southward  to  connect 
with  the  margin  of  the  Illinoian  already  traced  to  western  Scott  County. 
It  was  found  that  the  "Goose  Lake  Channel,"  described  by  McGee  as  an 
old  course  of  the  Mississippi,  cuts  through  this  belt  immediately  south  of 
the  village  of  Goose  Lake  (see  PI.  XVIII).  From  the  west  side  of  this  broad 
valley  the  belt  continues  nearly  due  west  across  northern  Washington  and 
Welton  townships,  occupying  its  usual  width  of  3  or  4  miles  and  constituting 
the  divide  between  the  Maquoketa  and  Wapsipinicon  rivers.  It  there  takes 
a  course  noi'th  of  west,  passing  between  Elwood  and  Lost  Nation  and  still 
constituting  the  water  parting  between  the  two  drainage  systems.  Slight 
incursions  into  the  district  north  of  this  belt  shoAved  only  thin  deposits  of 
drift  resting  on  or  mingled  with  residuary  clays.  The  thick  drift  was  traced 
to  the  vicinity  of  Onslow  in  Jones  County,  and  there  the  examination  was  dis- 
continued, for  it  had  become  evident  that  this  belt  of  drift  could  not  connect 
with  the  Illinoian  margin  in  Scott  County.  In  returning  eastward  it  was 
found  that  the  thick  drift,  with  its  heavy  coating  of  loess,  lies  along  the 
north  edge  of  a  plain  of  lowan  till,  strewn  with  the  immense  bowlders 
characteristic  of  that  deposit  and  presenting  only  thin  or  patchy  develop- 
ments of  the  loess. 

At  Dewitt  Prof  J.  A.  Udden  joined  the  writer  for  a  couple  of  days' 
study,  and  a  trip  was  made  together  from  Dewitt  to  Sabula.     The  large 
MON  xxxviii 10 


146  THE  ILLINOIS  GLACIAL  LOBE. 

lowan  bowlders  were  found  east  as  well  as  west  of  Goose  Lake  Channel, 
as  far  north  as  the  south  edge  of  the  belt  of  thick  drift,  but  were  not 
observed  .farther  north.  The  first  night  was  spent  at  Bryant,  near  the  north 
edge  of  the  belt  of  thick  drift,  and  in  the  vicinity  of  this  village  a  few 
exjDOSures  of  the  drift  were  found  at  the  base  of  the  loess,  all  of  which 
showed  a  leached  and  reddened  surface.  Continuing  northward  from 
Bryant  to  Miles  the  loess  was  found  to  remain  nearly  as  heavy  as  on  the 
belt  of  thick  drift,  but  the  g-lacial  deposits  were  very  much  thinner  and 
seemed  to  be  restricted  to  small  bowlders  and  pebbles  of  crystalline  pre- 
Cambrian  rocks.  These  were  usually  found  embedded  in  a  slightl}-  dis- 
turbed residuary  clay  of  a  deep  reddish-brown  color  which  can  scarcely  be 
called  till,  the  commingling  of  pebbles  with  i-esiduary  material  being  so 
im^jerfect.  Between  Miles  and  Sterling  the  sui-face  is  ridged  in  a  peculiar 
manner,  though  somewhat  similar  to  the  paha  of  the  neighboring-  county  on 
the  west  (Jones  County)  in  trend  and  form,  the  trend  being  WNW.  to  ESE. 
and  the  form  somewhat  similar  to  an  inverted  canoe.  The  wells  made  on 
these  ridges  were  reported  to  have  penetrated  "clay  and  quicksand,"  and  in 
some  cases  have  reached  a  depth  of  40  feet  without  entering  solid  rock.  As 
no  exposures  were  found,  the  precise  natm-e  of  the  deposits  remain  unde- 
termined. A  few  granitic  and  greenstone  pebbles  were  found  in  raA^iues 
between  Sterling  and  Sabula,  showing  that  the  glacial  deposits  occur  a  few 
miles  outside  the  limit  mapped  by  McGee. 

Reviewing  the  above  observations,  it  appears  that  nothing  to  suggest 
the  occurrence  of  lowan  drift  was  found  along  or  north  of  the  belt  of 
thickened  drift  except  the  paha-like  ridges  near  Miles,  and  there  the 
resemblance  is  not  known  to  carry  with  it  the  interpretation  that  they  are 
of  similar  origin  or  date  to  the  paha  of  the  clearly  recognized  lowan  drift. 
At  best  the  i)aha  are  still  an  enigma  from  which  as  yet  nothing  can  be 
proved.  In  view  of  the  very  thin  and  somewhat  jiatchy  development  of 
the  Iovv;ui  drift  near  tlie  terminus  of  the  lobe  in  Ogle  and  Lee  counties, 
Illinois,  some  hesitancy  is  felt  in  declaring  the  lowan  drift  to  be  absent  from 
northern  Clinton  and  southei'n  Jackson  counties,  Iowa.  For  in  tlie  latter 
counties  tlie  heavy  deposits  of  loess  greath*  interfere  witli  the  determination 
of  its  extent.  The  occurrence  of  a  sheet  of  drift  markedly  older  than  the 
lowan  in  the  district  mapj)ed  by  McGee  as  occu])ied  only  by  upper  till  is 
abundantly  evident.     The  thickened  bc^lt  of  this  ohler  drift  merits  further 


EXTENT  OF  IOWA  PORTION  OP  lOWAK  DRIFT.  147 

investigation,  especially  since  in  some  of  its  features  it  sugg-ests  a  terminal 
moraine. 

During  the  past  season  (1897)  the  writer,  together  with  Mr.  Oscar 
Hershey,  made  further  observations  in  eastern  Clinton  County,  Iowa,  as 
well  as  in  Hem-y,  Whiteside,  and  Carroll  counties,  Illinois.  At  Clinton  the 
glacial  deposits  on  the  bluff  of  the  Mississippi  are  found  to  be  very  thin, 
amounting  usually  to  but  5  or  10  feet.  These  deposits,  however,  appear 
to  be  capable  of  separation  into  two  distinct  till  sheets.  One  is  reddened 
and  leached  at  the  junction  with  the  overl3dug  loess  and  apparently  is 
nmch  older,  while  the  other  is  scarcely  at  all  leached  or  stained  at  the 
junction  with  the  loess  and  in  one  locality  appears  to  graduate  upward  into 
loess.  The  former  deposit  is  probably  of  Kansan  age  while  the  latter 
ajDpears  to  be  lowau.  The  best  exposure  noted  is  found  a  short  distance 
northwest  of  the  Clinton  Brewery  in  sec.  1,  Clinton  Township.  The  loess 
here  has  a  thickness  of  20  to  25  feet.  At  its  base,  near  tlie  east  end  of  the 
exposure,  is  a  fresh-looking  calcareous  till,  about  4  feet  thick,  resting  upon 
a  bed  of  rotten,  deeply  stained  gravel  which  there  caps  the  older  till.  A 
few  rods  west  the  older  till  comes  up  to  the  base  of  the  loess  and  farther 
west  there  are  several  exposures  in  which  the  loess  rests  directly  upon  the 
older  till.  Had  the  exposure  of  fresh  till  not  been  observed,  there  would 
have  been  nothing  to  indicate  the  presence  of  an  lowan  drift  at  this  locality. 
Such  being  the  case  here,  where  exposures  are  extensive,  it  can  scarcely  be 
afhrmed  that  the  lowan  drift  is  not  present  in  the  district  immediately  north 
and  west,  where  only  slight  exposures  can  be  found  beneath  the  heavj^ 
covering  of  loess.  The  exposure  just  mentioned  was  visited  in  November, 
1897,  by  Messrs.  Calvin,  Udden,  Bain,  and  the  writer,  and  the  interpreta- 
tion given  above  was  assented  to  without  reserve.  Hershey  and  the/writer 
noted  two  exposures  in  the  bluff  in  the  north  part  of  North  Clinton  (formerly 
Lyons)  in  which  a  few  feet  of  fresh-looking  till  rests  directly  upon  the 
residuary  clay  of  the  underlying  limestone,  a  till  which  seems  referable  to 
the  lowan  rather  than  Kansan.  Southwest  of  Clinton  along  the  Burlington, 
Cedar  Rapids  and  Northern  Railroad  bowlders  were  noted  by  Messrs.  Cal- 
vin, Udden,  Bain,  and  the  writer  near  the  east  bank  of  the  Mississippi. 
They  are  of  the  large  angular  type  recognized  by  Calvin  as  charactei'istic 
of  the  lowan,  and  they  occur  on  a  gently  undulatory  plain,  such  as  is  also 
characteristic  of  the  lowan.     Similar  bowlders  were  observed  by  the  same 


148  THE  ILLINOIS  GLACIAL  LOBE. 

part)'  of  geologists  near  Long  Grove  in  northern  Scott  County,  and  are 
reported  to  occur  for  several  miles  farther  east.  Here  also  they  occur  on  a 
plain  referred  with  some  confidence  to  the  lowan  stage  of  glaciation.  Hav- 
ing traced  undoubted  Towan  deposits  to  the  border  of  the  Mississippi,  it 
becomes  a  matter  of  interest  to  determine  whether  the  lowan  ice  crossed 
into  Illinois. 

The  examination  made  by  Mr.  Hershey  and  the  writer  in  Whiteside 
and  CaiToll  counties,  directly  east  from  the  district  just  discussed,  brought 
to  light  several  features  of  a  puzzling  nature,  some  of  which  may  have 
direct  bearing  upon  this  question.  These  features  fall  into  live  classes,  (I) 
fresh  till;  (2)  a  tract  free  from  loess;  (3)  a  sand  border  east  of  the  fresh  till; 
(4)  a  loess  apron  outside  the  sand  border;  (5)  ridges  of  loess  with  similar 
trend  to  the  paha  of  the  lowan  drift  area.  Certain  other  features  found  in 
southern  \yhiteside  and  northwestern  Henr}'  counties  are  considered  in  con- 
nection with  the  probable  extension  of  the  Illinois  lobe  at  the  lowan  stage. 
The  features  here  considered  lie  outside  the  prol^able  limits  of  that  lobe. 

Deposits  of  fresh-looking  till  occur  on  the  elevated  upland  about  10 
miles  due  east  of  the  north  part  of  Clinton,  near  the  south  line  of  sec.  13, 
Ustick  Township,  and  near  the  west  end  of  the  line  of  sees.  18  and  19, 
Clyde  Township,  Whiteside  County.  The  till  has  a  yellowish-gray  color 
similar  to  that  of  the  lowan  near  Polo,  in  Ogle  County,  and  effervesces  at  a 
depth  of  less  than  2  feet  from  the  surface  of  the  ground.  As  the  exposures 
occur  in  the  midst  of  a  tract  nearly  free  from  loess,  there  is  nothing  to 
protect  the  till  from  leacliing.  It  is  in  marked  contrast  to  numerous  other 
till  exposures  in  the  immediate  neighborhood,  which  show  decidedlv  stronger 
surface  stain  and  are  leached  to  a  depth  of  5  or  6  feet.  These  exposures 
of  fresh-looking  till  were  visited  by  Calvin,  Udden,  Bain,  and  the  writer  in 
November,  1897,  and  by  all  were  recognized  to  present  a  much  fresher 
appearance  than  the  surrounding  exposures.  It  was  also  recognized  that 
advantages  for  erosion  here  seem  no  greater  tliau  at  })oints  where  a  stained 
and  deeply  leached  surface  is  presented.  Althougli  several  ditferent  lines 
have  been  traversed  by  Hershey  and  the  writer  in  Carroll  and  western 
Whiteside  counties,  no  otiier  exposures  of  such  fresh  till  have  been  noted 
outside  of  tlie  possible  limits  of  tlie  lowan  sheet  formed  by  the  Illinois  lobe. 
These  exposures,  it  will  be  observed,  occur  witliin  tlie  limits  of  a  single 
square  mile.     Taken  by  themselves  they  seem  a  wenk,  tliougli  perliaps  not 


EXTENT  OF  IOWA  PORTION  OF  lOWAN  DRIFT.  149 

uncertain,  prop  to  support  the  hypothesis  of  an  extension  of  ice  from  Iowa 
into  Illinois  at  the  lowan  stage  of  glaciation. 

The  elevated  tract  just  noted  stands  near  the  south  end  of  a  strip  which 
is  nearly  free  from  loess.  The  strip  extends  northward  several  miles  into 
Carroll  County  and  has  a  general  width  of  only  about  2  miles.  It  is  in 
decided  contrast  with  the  thick  belt  of  loess  on  the  west  which  follows  the 
east  bluff  of  the  Mississippi  and  probably  averages  not  less  than  30  feet  in 
average  depth.  It  is  also  in  contrast  with  the  district  on  the  east  which  for 
a  distance  of  several  miles  back  is  covered  to  a  depth  of  12  to  15  feet  with 
loess.  On  the  south  also  there  is  heavy  loess  separating  this  tract  from  a 
similar  tract  south  and  east  of  Morrison.  The  tract  with  scanty  loess  is  in 
an  exposed  situation,  but  apparently  no  more  so  than  the  bluff  of  the  Mis- 
sissippi both  to  the  west  and  south.  It,  therefore,  seems  difficult  to  account 
for  its  scant  deposition  by  the  force  of  the  wind.  It  stands  like  the  fresh 
till  as  a  feature  out  of  harmony  with  the  general  features  of  the  region. 
It  seems,  however,  to  have  a  parallel  in  the  region  of  lowan  drift  to  the 
west,  where  similar  areas  free  from  loess  are  bordered  by  loess-covered 
tracts.  In  this  connection  it  ma}"  be  remarked  that  the  belt  of  loess  along 
the  Mississippi  bluff  leads  down  the  river  from  far  to  the  north  and  may  be 
somewhat  later  than  the  loess  to  the  east,  and  possibly  subsequent  to  the 
occupancy  of  eastern  Iowa  by  the  lowan  ice  sheet. 

East  of  this  tract  characterized  by  thin  loess  is  a  narrow  sandy  belt  in 
which  dunes  are  common.  This  belt  is  best  developed  in  Clyde  Township, 
Whiteside  County,  where  it  has  a  breadth  of  fully  1  mile.  Its  southern 
end  is  found  at  Rock  Creek  Valley  about  5  miles  above  Morrison,  as  indi- 
cated on  PI.  XII.  From  this  point  it  bears  slightly  west  of  north  into 
Carroll  County,  lying  mainly  east  of  the  valley  of  Little  Creek.  Its  general 
altitude  is  slightly  lower  than  the  tract  on  the  west,  but  it  has  about  the 
average  elevation  of  the  region,  being  not  less  than  200  to  250  feet  above 
the  Mississippi  River.  It  is  so  far  removed  from  the  river  as  to  be  outside 
the  range  of  the  eeolian  deposits  which  in  places  accumulate  on  the  east 
bluff.  The  best  developed  portion,  as  may  be  seen  by  reference  to  PL  XII, 
stands  6  to  10  miles  back  from  the  river  bluff  and  is  separated  from  it  by 
the  still  more  elevated  tract  just  discussed. 

On  the  south,  east,  and  north  borders  of  the  sandy  belt  there  is  a 
blanket  of  loess  12  to  15  feet  thick  near  the  margin  of  the  sand,  but  decreasing 


150  THE  ILLINOIS  GLACIAL  LOBE. 

in  thickness  to  scarcely  lialf  that  depth  within  a  few  miles  east  or  north, 
beyond  which  for  many  miles  it  continues  thin.  The  distribution  and 
general  relations  of  this  loess  in  reference  to  the  district  west  of  it  present 
some  points  of  similarity  to  the  loess  borders  of  the  loAvan  drift  in  north- 
eastern Iowa  where  the  loess  is  considered  an  outwash  or  overwash  apron 
from  the  ice  sheet,  formed  while  it  occupied  the  neighboring  tracts  of  lowan 
drift,  which  are  nearly  free  from  loess.  The  thinning  out  of  the  loess  upon 
passing  a  few  miles  back  from  the  hypothetical  ice  margin,  as  well  as  the 
abrupt  border  next  the  ice  margin,  may  liere  find  illustration  just  as  in 
Johnson  County,  lowa.^ 

The  remaining  feature  bearing  upon  the  question  of  the  Iowa  invasion 
into  northwestern  Illinois  is  that  of  canoe-shaped  ridges  of  loess,  with 
parallel  shallow  troughs,  having  a  WNW.-ESE.  trend.  Such  ridges  and 
troughs  are  best  developed  in  a  belt  of  thick  loess  lying  between  the  strip  of 
thin  drift  just  considered  and  the  valley  of  Eock  Creek  in  western  Whiteside 
County  (see  PI.  XVIII),  There  are  other  well-defined  ridges,  as  already 
noted,  south  and  east  of  Morrison,  in  the  lowland  tract  nearly  destitute  of 
loess,  and  a  few  have  been  found  south  of  Rock  River  in  northwestern  Henrv 
County.  There  is  a  faint  development  of  this  class  of  ridging  in  northern 
Rock  Island  County,  Illinois,  and  in  southern  Scott  and  eastern  Muscatine 
counties,  Iowa.  It  is,  perhaps,  significant  that  they  are  best  developed  in 
the  district  lying  between  the  well-defined  phases  of  the  lowan  drift  of  the 
two  ice  lobes.  While  the  origin  of  this  class  of  ridofes  like  that  of  the  loess 
sheet  is  in  all  probability  attributable  to  a  combination  of  aqueous  and 
seolian  agencies  the  precise  mode-  of  action  and  relation  of  the  two  agencies 
have  as  yet  received  no  adequate  explanation.  These  ridges  and  bordering 
troughs  were  apparently  developed  before  the  present  drainage  lines  had 
been  opened  in  that  region,  if  not  while  the  ice  occupied  the  neighboring 
drift  plains  on  which  the  loess  is  a  scanty  deposit.  The  length  of  the 
ridges  ranges  from  a  fraction  of  a  mile  to  two  or  three  miles,  but  the  width 
seldom  reaches  one-eighth  of  a  mile.  In  height  they  range  from  5  feet  or 
less  up  to  about  50  feet.  While  usually  made  up  of  typical  loess  they 
occasionally  include  fine  sand,  as  noted  above  (p.  139.) 

Aside  from  the;  canoe-shaped  ridges  of  loess  there  are  found  other  forms 
of  loess  and  sand  aggregation  in  the  region  under  discussion.     On  the  east 


1  See  Calvin,  Iowa  Geol.  Survey,  Vol.  VII,  1897,  pp.  86-90;  also  iiiup  of  .lohnson  County,  p.  92. 


EELATIOK  OF  ILLIISrOIS  AND  IOWA  ICE  LOBES.  151 

bluff  of  the  Mississippi  Valley,  opposite  the  broad  sandy  bottoms,  stich  as 
occur  in  southwestern  Carroll  and  northwestern  Whiteside  counties,  sandy 
knolls  and  ridges  are  found  which  are  evidently  due  to  wind  action.  Some 
of  them  are  in  process  of  drifting-  even  to-day,  for  the  sand  is  too  barren  to 
nourish  an  adequate  protective  cover  of  vegetation.  These  ridges  are 
irregular  in  form  and  trend  and  seldom  bear  a  resemblance  to  the  canoe- 
shaped  ridg-es  of  loess.  A  few  sandy  ridges  are  found  on  the  strip  of  drift 
in  southwestern  Carroll  County,  above  noted,  where  the  loess  is  scanty, 
which  like  the  canoe-shajjed  ridges  of  loess  have  a  general  WNW.-ESE. 
trend.  They  are,  however,  more  in-egular  in  form  and  are  usually  broader 
than  the  loess  ridges.     Possibly  they  should  be  classed  with  the  dunes. 

If  all  the  features  of  the  region  just  discussed  be  considered,  it  appears 
that  positive  e^adence  of  the  invasion  of  the  Iowa  ice  into  northwestern 
Illinois  at  the  lowan  stage  of  glaciation  is  at  best  very  weak.  The  features, 
however,  appear  to  favor  rather  than  to  antagonize  the  hypothesis  of  such 
an  invasion.  The  debatable  ground  is  restricted  to  a  belt  but  10  or  15 
miles  wide  on  the  north  and  east  borders  of  unquestioned  lowan  drift.  It 
embraces  northern  Clinton  and  southern  Jackson  counties,  Iowa,  and  south- 
western Carroll,  western  Whiteside,  and  possibly  neighboring  portions  of 
Rock  Island  County,  Illinois.  Were  this  belt  low,  like  the  tracts  occupied 
by  the  lowan  drift  in  Clinton  and  Scott  counties,  Iowa,  the  extension  might 
be  granted,  even  with  a  very  limited  occurrence  of  fresh-looking  drift.  But 
the  fact  that  the  debatable  region,  both  on  the  north  and  east,  stands  100 
to  300  feet  above  the  low  plain  of  lowan  drift,  necessitates  a  very  careful 
study  of  the  evidence  in  the  light  of  all  applicable  hypotheses.  Having  set 
forth  the  available  data,  the  question  is  left  open  with  the  hope  that  either 
by  the  light  of  further  data  or  by  more  mature  reflection  a  satisfactory 
solution  may  be  reached. 

RELATION    OF    THE    ILEIJfOIS    AJSTD    IOWA    ICE    I.OBES. 

In  concluding  this  discussion  a  few  remarks  seem  necessary  concerning 
the  probable  relation  of  the  Illinois  and  Iowa  ice  lobes  at  the  lowan  stage 
of  glaciation.  In  his  paper  on  northeastern  Iowa,  above  quoted,  McGee 
considers  it  probable  that  at  the  invasion  now  called  lowan  the  ice  from  the 
Iowa  side  culminated  earlier  than  that  on  the  Illinois  side,  and  caused  a 
displacement  of  the  drainage  of  the  Mississippi  near  Clinton,  southeastward 


152  THE  ILLINOIS  GLACIAL  LOBE. 

to  Rock  River.^  He  has  rejDresented  the  Illinois  lobe  to  have  subsequently 
extended  to  the  border  of  the  Mississippi  Valley  in  Wliiteside  and  Rock 
Island  counties,  and  to  have  led  to  the  flooding  of  the  Driftless  Ai-ea, 
forming  what  is  termed  Lake  Hennepin.^  It  would  appear  from  McGee's 
discussion  that  the  dates  of  culmination  of  the  two  lobes  were  separated  l^y 
only  a  brief  interval,  an  interval  which  in  no  wise  compares  in  length  with 
that  which  has  been  found  to  have  occurred  between  the  Kansan  invasion 
of  the  Iowa  lobe  and  the  Illinoian  invasion  of  the  Illinois  lobe,  and  that  one 
lobe  held  nearly  its  maximum  extent  until  the  other  culminated.  The  rela- 
tions of  the  two  lobes  of  the  lowan  invasion  appears  to  have  been  largelv  a 
matter  of  conjecture,  for  it  is  now  found  that  the  Illinois  lobe  fell  far  short 
of  reaching  the  limits  assigned  to  it  by  McGee.  It  is  doubtful  if  evidence 
has  yet  been  collected  by  which  it  will  be  possible  to  demonstrate  clearly 
either  the  space  or  the  time  relations  of  the  two  ice  lobes. 

The  space  relations  as  well  as  time  relations  of  the  two  lobes  being  still 
unsettled,  the  influence  upon  drainage  is  at  best  a  matter  of  conjecture. 
The  Iowa  ice  lobe  appears  to  have  reached  as  far  east  as  the  Mississippi 
River  in  southern  Clinton  and  northern  Scott  counties.  Possibly  it  reached 
a  few  miles  beyond  the  river  in  southwestern  Carroll,  western  Wliiteside, 
and  northern  Rock  Island  counties,  Illinois,  though  such  an  extension  is, 
as  already  noted,  but  weakl}^  supported.  The  Illinois  ice  lobe  certainly 
extended  a  few  miles  beyond  Sterling  on  the  north  border  of  Rock  River 
Valle)^  and  probably  extended  about  to  Geneseo,  on  the  south  border  of 
that  valley.  The  debatable  tract  east  and  south  of  Morrison,  in  central 
and  southern  Whiteside  County,  was  apparently  covered  at  the  lowan  stage, 
either  by  the  Illinois  or  by  the  Iowa  ice  lobe.  If  the  latter  is  found  not  to 
have  extended  beyond  the  Mississippi  Valley,  it  would  follow  that  this 
district  was  occupied  by  the  Illinois  lobe. 

The  question  of  a  coalescence  of  the  two  lobes,  or  the  overlapping  of 
their  fields,  depends,  therefore,  upon  the  determination  of  the  extent  of  tlie 
Iowa  lobe.  If  that  lobe  did  not  extend  beyond  the  Mississippi,  there  would 
remain  a  strip  about  8  miles  in  width  along  the  east  border  of  tlie  Missis- 
sippi Valley  which  remained  uncovered  by  ice  throughout  the  lowan 
invasion.     By  including  the  valley  its  width  woilld  be  increased  to  10  or 

'  Eleventh  Ann.  Kept.,  U.  S.  Geol.  Survey,  p.  570. 
2  Op.  cit.,  PI.  lA^II;   mIso  pp.  r>70-r>77. 


THE  lOWAN  LOESS.  153 

12  miles;  it  would  embrace  the  belt  of  heavy  loess  west  of  Kock  Creek,  in 
Whiteside  Comity,  at  the  points  where  the  lobes  made  theii'  closest 
approach.  A  belt  of  this  width  would,  when  taken  in  connection  Avith  the 
valley  of  the  Mississippi  River,  apparently  have  afforded  an  adequate  line 
of  discharge  for  the  streams  of  the  Driftless  Area,  and  also  for  the  waters 
issuing  from  the  melting  ice  lobes.  If,  on  the  other  hand,  the  Iowa  lobe 
extended  to  the  ^dcinity  of  Round  Grove  and  Spring  Hill,  Illinois  (see  PL 
XII),  and  reached  this  culmination  at  the  same  time  that  the  Illinois  lobe 
had  its  maximum  extension,  there  may  have  been  a  coalescence  of  ice  for  a 
breadth  of  perhaps  15  or  20  miles.  This  appears  to  re^iresent  the  extreme 
possibility  of  coalescence.  Granting-  such  coalescence,  it  remains  question- 
able whether  a  glacial  lake  could  have  been  held  in  the  region  north  of  the 
junction  of  the  lobes.  The  existence  of  Lake  Hennepin  appears,  therefore, 
to  rest  upon  exceedingly  weak  foundations  so  far  as  the  influence  of 
coalescing  ice  lobes  is  concerned.  It  is  doubtful  if  a  body  of  water  of 
greater  depth  was  present  in  the  district  north  of  these  lobes  than  in  the 
district  south  of  them.  It  is  generally  supposed  that  the  loess  was  deposited 
under  conditions  of  very  imperfect  drainage,  and  that  the  districts  which  it 
covers  were,  in  large  part,  under  water  for  at  least  brief  intervals.  The 
extent  and  duration  of  the  flooding,  both  to  the  north  and  south  of  the 
districts  occupied  by  these  ice  lobes,  is  still  largely  a  matter  of  conjecture, 
and  a  subject  on  which  wide  differences  of  opinion  exist.  With  these 
remarks  we  pass  to  the  discussion  of  the  lowan  loess. 

THE  lOWAiy  LOESS. 

DISTRIBUTION. 

Deposits  of  silt,  tentatively  classified  with  the  loess  and  supposed  to  be 
of  lowan  age,  cover  the  entire  surface  of  the  Illinoian  didft  so  far  as  it  lies 
outside  the  limits  of  the  lowan  and  Wisconsin  drift  sheets,  not  only  in  Illi- 
nois, but  also  in  Iowa  and  in  States  to  the  east  as  far  as  Ohio.  These 
deposits  have  been  extensively  removed  by  stream  erosion  on  a  consider- 
able paii;  of  the  slopes  and  in  the  valley  bottoms,  but  still  remain  nearly 
intact  on  the  uplands.  They  have  been  traced  back  several  miles  beneath 
the  edge  of  the  Wisconsin  drift  in  central  and  eastern  Illinois,  but  the  full 
extent  has  not  been  ascertained.     A  portion  of  the  Driftless  Area  in  Illinois, 


154  THE  ILLINOIS  GLACIAL  LOBE. 

both  in  the  northwest  corner  and  in  the  southern  end  of  the  State,  were 
ahnost  entirely  covered  by  loess,  though  possibly  some  of  the  highest  knobs 
and  ridges  escaped. 

In  northern  Illinois,  where  the  lowan  drift  sheet  is  exposed  to  view 
outside  the  limits  of  the  Wisconsin,  the  loess-like  silts  are  in-egularly  dis- 
tributed. The  Pecatonica  lobe  and  the  districts  to  the  east,  in  Winnebago, 
Boone,  western  McHenry,  and  northern  Dekalb  counties,  have  scarcely 
any  typical  loess,  and  the  silt  deposits  seldom  exceed  a  depth  of  1  or  2  feet. 
It  is  not  certain  that  these  deposits  are  of  similar  origin  and  date  to  the  silt 
deposits  on  the  west  border  of  the  lowan  di-ift.  In  passing  southward  from 
the  Pecatonica  lobe  loess-like  silts  overlap  the  lowan  drift  to  a  distance  of 
several  miles.  In  northern  Lee  County  Illinois,  they  extend  some  miles  east 
of  Rock  River.  Upon  approaching  the  Green  River  Basin  sandy  deposits 
appear  which  effectually  conceal  any  silts  which  may  have  been  deposited 
farther  south.  However,  the  belt  of  drift  thought  to  be  of  lowan  age  that 
is  situated  on  the  south  border  of  the  Green  River  Basin  is  not  sand  covered. 
This  has  a  much  thinner  deposit  of  silt  than  the  lUinoian  sheet  to  the  south, 
and  much  of  its  surface  seems  never  to  have  been  coated  with  silt. 

Attention  has  been  called  to  the  existence  of  a  tract  neaidy  free  from 
loess  in  southwestern  Carroll  and  northwestern  Whiteside  counties,  Illinois, 
which  may  find  its  explanation  in  ice  occupancy  of  the  territory  up  to  a 
date  so  late  that  the  loess  was  barred  out.  There  are  quite  extensive  loess- 
covered  tracts  within  this  area,  notably  one  which  follows  the  Mississippi 
Valley.  This  belt  of  loess  seems  to  be  a  continuation  of  the  extensive  belt 
which  follows  the  west  side  of  the  Driftless  Ai-ea  throughout  almost  its  entire 
length,  and  is  perhaps  somewhat  later  than  the  loess  deposits  made  on  uplands 
below  the  Driftless  Area.  Aside  from  this  main  belt  along  the  Mississippi 
River  there  is  a  heavy  loess  deposit  in  northern  Whiteside  County,  which 
is  probably  as  old  as  the  loess  on  the  disti'icts  to  the  east.  Loess  is  also 
found  on  much  of  the  narrow  uplands  lying  between  Rock  and  Green  rivers 
from  Spinng  Hill  southwestward  to  the  junction  of  these  streams.  In  addi- 
tion to  the  loess  which  is  deposited  in  sheets  there  is  in  this  region  a  loess 
capping  the  paha  ridges.  In  some  cases  the  paha  are  coated  to  a  dejith  of 
15  feet  or  more,  while  bordering  plain  tracts  are  nearly  free  from  loess.  In 
other  cases  the  loess  appears  to  be  nearly  as  henvy  on  the  plain  tracts  as 
on  the  paha.     The  distribution  in  the  lowan  area  is  so  irregular  and  patchv 


THE  lOWAIT  LOESS.  •  155 

that  very  detailed  study  is  necessary  to  determine  its  limits.  The  general 
extent  of  the  loess  and  associated  silts  may  be  seen  by  reference  to  the 
glacial  map  (PL  VI). 

VARIATIONS    IN     THICKNESS. 

The  variations  in  thickness  of  the  loess  apparently  depend  largely 
upon  the  relation  (1)  to  the  ice  margin  and  (2)  to  the  principal  lines  of 
drainage.  On  the  margin  of  the  lowan  ice  sheets,  especially  the  one  which 
occupied  eastei'ii  Iowa,  there  is  a  thicker  deposit  of  loess  than  in  districts 
remote  from  the  ice  margin.  Also  in  Carroll  and  Whiteside  counties,  Illi- 
nois, there  is  a  belt  of  loess  extending  from  the  hypothetical  margin  of  the 
lowan  ice  sheet  above  outlined  northward  to  the  south  border  of  the 
Pecatonica  Basin  and  eastward  to  Elkhorn  Creek,  in  which  the  loess  has  a 
thickness  of  15  to  20  feet,  while  in  the  districts  immediately  north  and  east 
its  average  thickness  does  not  much  exceed  5  feet.  The  features  here  as 
well  as  elsewhere  seem  to  indicate  that  the  outwash  from  the  lowan  ice 
was  much  heavier  within  10  or  15  miles  from  its  border  than  at  ffreater 
distances.  The  ice  lobe  which  extended  southwestward  into  northern  Illi- 
nois has  a  less  marked  thickening  of  the  loess  near  its  border,  though  Mr. 
Hershey  reports  a  perceptible  thickening  on  the  borders  of  the  Pecatonica 
lobe.  On  the  south  border  of  the  Green  River  Basin  there  is,  however,  a 
marked  thickening  of  the  loess  at  the  line  supposed  to  mark  the  southern 
limits  of  the  lowan  ice  sheet.  The  thickness  is  nowhere  much  less  than  25 
feet  and  in  places  is  fully  40  feet.  Upon  passing  southward  the  thickness 
soon  decreases  to  12  or  15  feet,  and  about  this  thickness  is  maintained  over 
much  of  the  area  between  the  Illinois  and  Mississippi  rivers. 

The  thickening  of  the  loess  along  the  borders  of  the  main  drainage 
lines  is  well  illustrated  by  the  Mississippi.  On  the  borders  of  this  valley 
in  northern  Illinois  there  is  25  to  40  feet  of  loess,  but  within  5  or  10  miles 
east  of  the  bluff  the  thickness  usually  decreases  to  less  than  10  feet. 
Following  down  the  Mississippi,  there  is  found  to  be  a  heavy  deposit  of 
loess  on  its  immediate  borders,  passing  through  the  area  which  was  occupied 
or  closely  bordered  by  the  lowan,  as  well  as  in  districts  to  the  north  and 
south,  a  feature  which  seems  to  indicate  that  the  loess  deposition  occurred 
after  the  withdrawal  of  the  ice  lobe  to  the  west  side  of  the  rivei'.  Upon 
passing  into  the  district  south  of  the  limits  of  the  lowan  ice  lobe  the  loess 


15f5  THE  ILLINOIS  GLACIAL  LOBE. 

decreases  in  thickness,  especiallj"  on  the  Iowa  side  of  the  river.  From  a 
thickness  of  40  feet  at  Muscatine  it  decreases  to  but  10  or  12  feet  at 
Burhngton  and  to  about  6  feet  at  Fort  Madison.  On  the  east  side  of  the 
river,  however,  the  loess  maintains  a  thickness  somewhat  greater  than  on 
the  west,  there  being  immediately  opposite  Fort  Madison  twice  as  thick  a 
dejjosit  as  on  the  Iowa  side.  This  extra  thickness  is  perhaps  attributable 
to  wind,  for  along  the  eastern  bluff  of  the  river  there  are  dunes  composed 
of  fine  sand  drifted  by  the  wind  from  the  broad  bottoms.  The  prevailing 
wind  being  from  the  southwest,  the  dunes  are  found  only  on  this  bluff. 

The  Illinois  Valley  is  bordered  both  on  the  east  and  west  below  the 
mouth  of  the  Sangamon  River  by  heavy  accumulations  of  loess,  40  to  50 
feet  or  more.  But  upon  passing  back  a  distance  of  5  or  10  miles  from  the 
stream,  on  either  side,  the  thickness  becomes  reduced  to  8  or  10  feet.  The 
heavy  loess  of  the  Illinois  and  Mississippi  valleys,  tog-ether  with  a  belt 
along  the  Missouri  valley,  continues  down  the  Mississippi  to  the  Gulf  of 
Mexico.  On  the  borders  of  southern  Illinois  the  thick  loess  is  confined  to 
a  belt  but  5  or  10  miles  in  width,  the  thickness  farther  east  being  scarcely 
one-fourth  as  great  as  on  the  immediate  borders  of  the  stream.  In  central 
and  southern  Illinois  the  thickness  of  the  loess  seldom  exceeds  10  feet  and 
probably  averages  not  more  than  6  feet.  The  Kaskaskia,  Emban-as,  and 
other  streams  of  south-central  and  southern  Illinois  do  not  have  such  heavy 
belts  of  loess  on  their  borders  as  characterize  the  Illinois,  Mississippi,  and 
Missouri  valleys.  There  is  but  little  thickening  u^jon  approaching  the 
Wabash  River,  the  average  thickness  along  the  west  bluff'  of  tlie  stream 
being  less  than  10  feet. 

On  the  lower  portion  of  the  Ohio  from  near  Rockport,  Indiana,  to  its 
mouth,  loess  deposits  are  15  to  25  feet  in  thickness,  but  above  Rockport 
the  thickness  is  seldom  more  than  5  or  6  feet,  and  this  thickness  prevails 
over  southeastern  Indiana  and  southern  Ohio. 

STRUCTURE. 

The  loess  and  associated  silts  are  not  so  uniform  in  structure  as  might 
be  inferred  frojn  some  of  the  published  descriptions.  The  earlier  descrip- 
tions apply  to  a  very  porous  deposit  found  on  the  borders  of  the  large 
vallej's  which  was  the  first  to  attract  the  notice  of  geologists  and  which 
may  be  designated  liluff  loess.     The  great  extent  of  the  surface  silt  over 


THE  lOWAX  LOESS.  157 

the  plains  between  the  streams  has  been  known  for  only  a  few  years.  In 
the  region  under  discussion  the  first  recognition  of  the  interfluvial  silts  as 
a  deposit  distinct  from  the  glacial  drift  appears  to  have  been  made  by 
Professor  Salisbury  in  his  studies  on  the  borders  of  the  Driftless  Area  in 
1885  and  in  southern  Illinois  at  a  later  date.  The  discussion  of  loess  in 
the  Illinois  geological  reports  apply  chiefly  to  the  deposits  on  the  immediate 
borders  of  the  main  valleys,  though  some  recognition  of  its  extent  into 
the  region  about  Springfield  appears  to  have  been  made  by  Professor 
Worthen  and  his  associates. 

The  structure  of  the  loess  varies  in  vertical  sections  as  well  as  from 
place  to  place.  The  leading  vai'iations  in  the  vertical  sections  are  such  as 
to  support  a  threefold  division :  (1)  The  surface  portion,  2  to  4  feet  in 
depth,  which  has  an  earthy  structiire  due  probably  in  part  to  the  breaking 
down  of  many  of  the  grains  under  atmospheric  action.  This  phase  charac- 
terizes not  oidy  the  deposits  on  interfluvial  tracts,  but  also  those  on  the 
borders  of  the  main  valleys,  as  is  natural  if  the  earthy  appearance  is  due  to 
atmospheric  action.  (2)  The  main  body  of  the  loess,  Avhich  is  a  silt  usually 
without  definite  bedding  planes  or  stratification.  It  is  somewhat  more 
porous  on  the  borders  of  the  main  valleys  than  beneath  the  interfluvial 
tracts.  The  variation  in  texture  is  apparently  due  to  the  removal  of  the 
finer  material  on  the  borders  of  the  valleys  rather  than  to  the  presence  of 
coarser  material  there  than  in  the  interfluvial  tracts.  (3)  The  basal  por- 
tion, which  commonly  shows  a  more  distinct  bedding  than  the  body  of  the 
loess,  and  is  in  places  sandy  and  pebbly.  As  a  rule  the  pebbles  are  con- 
fined to  the  lower  2  or  3  feet,  but  in  the  thicker  portions  of  the  loess  the 
well-defined  bedding  may  occupy  a  depth  of  several  feet.  The  pebbles 
often  occur  in  jjlaces  where  the  bedding  is  not  distinct.  Indeed,  the  most 
distinctly  bedded  portions  are  iisually  almost  free  from  pebbles. 

In  following  the  loess  from  place  to  place  across  the  interfluvial  tracts 
it  is  found  to  undergo  gradual  changes  in  texture  and  color,  for  which  a 
cause  is  not  in  all  cases  manifest.  But  as  a  rule  the  more  porous  portions 
of  the  loess  are  found  in  proximity  to  a  large  valley  or  to  the  border  of  the 
lowan  drift  sheet.  Upon  passing  back  from  the  valleys  the  open  texture 
becomes  less  pronounced,  and  there  is  a  gradual  change  to  a  clayey  loam 
and  then  to  loamy  clay.  A  similar  change  in  texture  is  found  in  ^jassing 
away  from  the  border  of  the  lowan  drift  sheet.     This  is  well  shown  both  in 


158  THE  ILLINOIS  GLACIAL  LOBE. 

southeasteni  Iowa  and  western  Illinois.  In  the  vicinity  of  Iowa  City,, 
along  the  borders  of  the  lowan  drift  sheet,  the  loess  is  so  porous  that  Avater 
readily  penetrates  it  and  tile  draining  is  seldom  necessary.  But  ujjon 
j^assing  southward  across  Washing-ton,  Louisa,  Henry,  and  Des  Moines 
counties,  the  texture  becomes  g-radually  finer,  and  extensive  areas  in  the 
southern  part  of  the  State  require  tile  draining.  In  northeastern  Missouri 
the  texture  is  still  more  compact,  so  that  a  large  portion  of  the  rainfall  is 
disposed  of  by  surface  evaporation.  Similarly  in  western  Illinois  the  loess 
of  Henry,  Rock  Island,  and  Mercer  counties  is  more  porous  than  that  of 
counties  immediateh'  south.  But  in  this  region  the  belt  of  porous  loess 
along  the  Mississippi  and  that  along  the  Illinois  occupv  so  much  of  the 
interval  between  the  streams  that  there  remains  onlv  a  narrow  strip  of 
compact  loess  in  the  vicinity  of  the  divide.  East  from  the  Illinois  River, 
as  far  as  the  divide  between  this  stream  and  the  Kaskaskia,  the  loess  is 
sufficientl}^  porous  to  require  but  little  tile  draining.  The  Kaskaskia 
drainage  basin  and  much  of  southern  Illinois,  like  northern  Missouri,  has  a 
surface  silt  too  compact  to  absorb  the  rainfall.  The  loess  in  this  region  has 
become  so  puddled  (perhaps  because  of  the  process  of  soaking  and  drying 
to  which  it  has  been  subjected)  that  underdrainage  is  difficult.  Through- 
out much  of  the  region  a  hard  ferruginous  crust  immediately  underlies  the 
soil  at  a  depth  of  12  to  15  inches  or  less,  which  needs  to  be  broken  before 
underdrainage  can  be  established.  The  compact  silts  of  southern  Illinois 
present  an  ashy  appearance  near  the  surface,  which  gives  them  the  name 
of  "white  clay."  It  is  rare  to  find  even  an  inch  of  black  soil  on  their  sur- 
face. In  this  respect  they  are  in  striking  contrast  to  the  silts  west  of  the 
Kaskaskia  Basin,  in  which  a  black  soil  several  inches  in  depth  is  generally 
present.  The  white  clay  district  is  continued  eastward  into  Indiana  and 
southwestern  Ohio,  occujjying  much  of  the  interval  between  the  glacial 
boundary  and  the  southern  edge  of  the  Wisconsin  drift  sheet. 

The  mineralogical  constitution  of  the  loess  and  determinations  of  the 
size  of  its  grains  has  been  given  considerable  attention  ])v  SalisburA",  and 
the  results  are  presented  in  the  Sixth  Annual  Report  of  this  Survey.  The 
samples  selected  were  chiefly  from  localities  adjacent  to  the  Driftless  Area 
on  each  side  of  the  Mississij)pi.  It  was  found  that  of  150,<S,S7  ])articles 
measured,  146,894,  or  about  97.^  i)er  cent,  are  less  than  0.005  millimeter  in 
diii meter,  leaving  only  2jj'  per  cent  of  greater  size.     The  largest  particles 


THE  low  AN  LOESS.  159 

noted  were  of  a  flattened  form,  many  of  them  being  mica  scales.  The 
extreme  size  noted  was  0.1139  by  0.0285  millimeter.  A  prominent  charac- 
teristic of  the  loess  g-rains  is  their  angularity  and  their  irregularity.  "kSharp 
corners  and  rough  surfaces  are  the  rule  and  any  approach  to  regularit)'  or 
smoothness  the  exception."  The  mineraldgical  examination  shows  that 
quartz  greatly  preponderates,  while  particles  of  feldspar,  mica,  hornblende, 
augite,  magnetite,  dolomite,  and  calcite  are  present,  the  mineral  constitution 
being  not  greatly  different  from  that  of  the  glacial  deposits  from  which  the 
loess  is  probably  largely  derived.  It  is  found  that  loess  in  the  Driftless  Area 
has  been  modified  by  the  introduction  of  residuary  material,  and  is  therefore 
formed  in  part  of  true  loess  material  and  in  part  of  wash  from  the  residuary 
soil  of  the  surrounding  country.^ 

Samples  of  the  several  grades  of  loess  were  collected  in  1892  by  the 
writer  in  various  parts  of  western,  central,  and  southern  Illinois  and  sent  to 
Prof  Milton  Whitney,  of  the  United  States  Department  of  Agriculture,  for 
mechanical  analysis.  Several  samples  were  analyzed  under  Professor 
Whitney's '  direction  by  Prof  J.  A.  Udden.  The  separations  were  made 
substantially  after  Johnson  and  Osborn's  "beaker  method."  The  results 
have  been  published  by  Whitney  in  a  report  to  the  Illinois  Board  of  World's 
Fair  Commissioners.'  The  following  tables,  taken  from  Whitney's  report, 
are  rearranged  to  bring  out  the  distinction  between  loess  supposed  to  have 
been  wind  dejjosited  and  that  which  may  liave  been  deposited  bv  water. 
Other  changes  in  the  grouping  of  the  analyses  have  also  been  made.  The 
analyses  of  bowlder  clays  are  introduced,  in  order  that  their  physical  con- 
stitution may  be  compared  with  that  of  the  loess  and  white  clay.  It  will  be 
observed  tliat  in  the  bowlder  clay  the  percentage  of  fine  material  (0.005 
millimeter  or  less)  is  greater  than  in  typical  loess,  thus  suggesting  the  partial 
removal  of  such  material  from  the  loess.  The  tables  bring  out  clearly  the 
fact  that  the  pervious  loess  contains  a  smaller  percentage  of  fine  particles 
than  the  compact,  but  that  it  contains  no  coarse  particles.  They  also  show 
that  in  the  pervious  loess  the  soil  contains  a  larger  percentage  of  fine  particles 
than  the  subsoil.  Whitney  remarks  that  the  loess  soil  and  subsoil  show  the 
reverse  of  the  rule  in  agricultural  lands,  it  being  the  rule  that  the  subsoil 

f         

'  Sixth  Ann.  Kept.  TJ.  S.  Geol.  Survey,  pp.  278-285. 

-Report  on  the  esaniiuatiou  of  some  soils  from  Illinois,  by  Milton  Whitney.  Final  Report  of 
Illinois  Board  of  World's  Fair  Commissioners,  1893,  pp.  93-114.  Published  at  Springfield,  Illinois,  in 
1895.     H.  W.  Rokker  Priuting  Company. 


160  THE  ILLINOIS  GLACIAL  LOBE. 

contains  a  greater  percentage  of  line  particles  than  the  soil.  An  interesting 
conti'ast  between  loess  and  residnary  earths  is  thus  indicated.  As  noted 
above,  the  surface  portion  of  the  loess  probably  owes  its  finer  constitution 
in  part  to  atniosphei'ic  action,  thi-ough  a  breaking  up  of  the  particles.  It 
is  probable  also  that  dust  transported  by  the  wind,  and  very  fine  material, 
such  as  is  constantly  floating  in  the  atmosphere,  tend  to  increase  the 
percentage  of  fine  material  at  the  surface.  There  may  also  have  been  an 
original  difference  in  the  coarseness,  for  there  is  generalh*  found  to  be  ai". 
increase  in  porosity  toward  the  base  of  the  loess. 

In  the  table  of  wind-deposited  soils  two  analyses  of  fine  sand  are 
included,  one  sample  obtained  at  Mason  Citv  on  the  east  border  of  a  sand- 
covered  basin  along  the  Illinois,  the  other  from  a  belt  of  sand  which  fringes 
the  Sangamon  River  bluffs  in  northern  Christian  County.  The  entire 
absence  of  coarse  sand  in  these  deposits  distinguishes  them  from  water- 
bedded  sand  on  the  terraces  of  neighboring  streams.  Analysis  Xo.  1338, 
from  an  Illinois  River  ten-ace  where  stream  action  was  operative,  shows 
nearly  5  per  cent  of  coarse  sand. 

The  final  tabic  presents  analyses  of  a  variety  of  soils.  Two  of  these 
(the  gumbo  from  Mississippi  bottoms  near  East  St.  Louis  and  the  soil  from 
the  old  lake  bottom  near  Chicago)  contain  a  greater  percentage  of  clay 
than  is  found  either  in  the  compact  loess  or  the  bowlderv  clay.  All  other 
analyses  of  water-deposited  silts  and  sands  from  Illinois  indicate  a  partial 
removal  of  the  clay  or  fine  material,  Ijut  in  these  samples  there  appears  to 
have  been  an  accession  or  concentration  of  this  material.  The  sample  fx'oni 
Rockford  represents  a  thin  deposit  of  silt  capping  the  lowan  till  slieet.  It 
contains  coarser  particles  tlian  are  found  in  the  loess  outside  the  border  of 
the  lowan  drift. 

In  com])aring  the  measurements  given  in  these  tables  witli  those  made 
by  Salisbury  it  sliould  be  borne  in  mind  that  Sali.sbury's  measurements 
refer  to  nunilxn-  of  grains,  while  Whitney's  refer  to  tlie  bulk  of  tlie  material. 
The  percentage  in  number  of  grains  in  Whitney's  tables  may  be  readily 
estimated  from  the  data  presented  in  the  column  showing  the  nuralier  of 
gi-ains  per  gram.  Thus  at  Virginia  City  the  subsoil  analysis  (No.  1318) 
shows  about  96  ])er  cent,  and  that  at  Dubuque  (No.  1347)  .sliows  97.7  per 
cent  below  0.()().5  millimeter  in  dianreter.  As  the  average  of  Salisbury's 
analyses  show  that  alxmt  97^  per  cent  fall  below  O.OOo  millimeter  in 
diameter,  the  results  obtained  are  very  similnr  tu  those  obtainiMl  hy  Whitney. 


ANALYSES  OF  BLCTFF  LOESS. 


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-11 


162 


THE  ILLINOIS  GLACIAL  LOBE, 
Table  III. —  Upland  loess,  pervious  to  water. 


Diameter  in 
millimeters. 


2-1 

1-.5 

.5-.  25 

.25-1 

.1-.05 

.05-.  01 

.01-.  005 

.005-.  0001... 


Conventional  names. 


Fine  gravel 

Coarse  sand 

Medium  sand  .. 

Fine  sand 

Very  fine  sand  . 

Silt 

Fine  silt 

Clav 


Total  mineral  matter . 
Organic  matter,  water,  loss. 


Loss  by  direct  ignition  . 


(1328)  'Wyomingsoil,  1-15    (1307)  Carrollton  soil.  1-15 
inches.  inches. 


Per  cent. 


Percent. 


100.  00 


100. 00 
6.14 


Grains 
per  gram. 


0 
0 
1 

57 

180, 500 

13,  890,  000 

153,  000,  000 

10, 970,  000,  000 


(1308)  Carrollton  subsoil, 
24-44  inches. 


Per  cent. 


0.00 
0.10 
0.87 
1.00 
6.17 

62.58 
8.76 

12.52 


100.00 
4.16 


Grains 
per  gram. 


0 

2 

129 

1,462 

114,  600 

18, 170,  000 

162,  700,  000 

5,916,000,000 


11, 137, 070,  558  |         92.  00  :       6.  096, 986, 193 

, [       8.00 ; 


Table  IV. —  Upland  loess,  almost  impervious  to  water.''- 


Diameter 
in  mil- 

Conventional names. 

(1321)  Greenville  soil, 
2-15  inches. 

(1342)  Northern  Cum- 
berland County  soil, 
1-12  inches. 

(1345)  "Western  Jeffer- 
son County  soil, 
2-15  inches. 

(1343)  Moweaqua  *5il, 
2-18  inches. 

limeters. 

Per 
cent. 

Grains  per 
gram. 

Per 

cent. 

Grains  per 
gram. 

Per 
cent. 

Grains  per 
gram. 

Per 

cent. 

Grains  per 
gram. 

2-1 

Fine  gravel 

Coarse  sand 

Medium  sand 

0.48 

1.92 

1.22 

0.58 

5.08 

59.06 

11.09 

14.12 

1 

35 

178 

65, 130 

92,  790 

16,  870,  000 

202, 100,  (100 

6, 564, 000,  OOO 

0.30 

1.05 

3.42 

3.30 

6.47 

55.48 

11.70 

14.90 

1 

18 

483 

4,595 

114,400 

15, 340, 000 

206, 900,  000 

6,707,000,000- 

0.00 
0.07 
0.29 
0.40 
6.38 
56.92 
12.18 

0 

1 

42 

577 

116,  900 

16,  290,  000 

221.  800.  000 

0.00 
0.08 
0.77 
0.11 
4.88 
52.50 
12.15 

0 

1-.5 

.5-.  25 

25-.  1 

1 

113 

13, 110 

.1-.05 

.05-.  01  

Very  fine  sand 

Silt 

89,280 
16, 020, 000 

01-. 005 

221.600.000 

.OO5-.O001.. 

Clay  

17.06    7,948,000,000 

22. 10   10,  300,  000,  000 

Total  mineral  matter 

Organic  matter,  vrater,  loss 

93.54 
6.46 

0,  783, 128, 134 

96.62 
3.38 

6, 929,  359, 497 

93.30 
6.70 

6, 186, 206,  520 

93.39 
6.61 

10, 536,  722, 504 

100.00 
5.59 

100. 00 
3.11 

100. 00 

100.00 
5.73 

Loss  by  dir 

4.49 

^Professor  TTdden  states  that  the  coarse  particles  found  in  these  samples  are  usually  concretions  of  iron  oxide, 
instead  of  sand  grains  or  pebbles.  It  is  probable  that  the  sand  seldom  exceeds  the  diameter  .25-. 1,  or  the  grade  called  fine 
sand. 


ANALYSES  OF  BOWLDER  CLAYS,  ETC. 


163 


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164 


THE  ILLI2«J^OIS  GLACIAL  LOBE. 


Several  cliemical  analyses  of  the  loess  have  been  made  which  repre- 
sent its  structure  at  widel}^  different  points.  The  first  four  analyses  in  the 
table  below  were  made  by  R.  B.  Riggs,  of  the  U.  S.  Geological  Surve}^,  in 
connection  with  Chamberlin  and  Salisbury's  study  of  the  loess  bordering 
the  Driftless  Area,  and  were  published  in  their  paper  in  the  Sixth  Annual 
Report  of  this  Survey.  No.  1  was  taken  from  the  summit  of  a  ridge  in  the 
suburbs  of  Dubuque,  Iowa,  at  a  point  about  300  feet  above  the  Mississippi 
River.  No.  2  represents  a  7-foot  stratum  of  loess  lying  over  brown  residu- 
ary clay  near  Galena,  Illinois,  at  about  350  feet  above  the  Mississippi  River. 
No.  3,  from  Kansas  City,  Missouri,  was  chosen  as  a  representative  of  the 
most  pronounced  loessial  characters  at  that  locality.  No.  4  was  taken  from 
aear  the  center  of  Vicksburg,  Mississippi,  about  200  feet  above  the  Missis- 
sippi River,  and  probably  fairly  rejjresents  the  upper  half  of  the  stratum 
there,  but  not  the  lower  portion,  which  seemed  heterogeneous.  The  remain- 
ing two  analyses  were  made  by  Prof.  W.  A.  Noyes  for  Dr.  J.  T.  Scovell, 
and  are  published  in  the  Twenty-first  Annual  Report  of  the  Indiana  Geo- 
logical Survey.  They  are  designed  to  illustrate  the  constitution  of  the 
white  clay  east  of  the  Wabash  River,  near  Terre  Haute,  Indiana.  No.  5 
represents  the  subsoil,  the  sample  being  from  a  depth  of  about  22  inches. 
No.  6  represents  a  sample  from  a  depth  of  only  10  inches.  The  samples 
analyzed  by  Mr.  Riggs  were  dried  at  100°  C;  those  analyzed  by  Professor 

Noyes  at  135°. 

Table  of  analyses  of  loess. 


SiO, 

A1,0:,.... 

Fe.O,  .. 

FeO 

TiO:  ... 
P2O.',.... 
MnO  ... 
CaO.... 
MgO  ... 
Na;0.-. 
K,0.... 
H;0  (a) 
CO,.... 

SO3 

C 


No.  1.— Da- 
buque. 


72. 68 

12.03 

3.53 

.96 

.72 

.23 

.06 

1.59 

1.11 

1.68 

2.13 

2.50 

.39 

.51 

.09 


No.  2.— Ga- 
lena. 


64.61 

10. 64 

2.61 

.51 

.40 

.06 

.05 

5.41 

3.69 

1.35 

2.06 

2.05 

6.31 

.n 

.13 


N0.3.— 
Kansas 

Citv. 


74.46 

12.26 

3.25 

.12 

.14 

.09 

.02 

1.69 

1.12 

1.43 

1.83 

2.70 

.49 

.06 

.12 


99.78 


100.  21  99.  99 

i 

(r(.'uulains  H  of  orjiaiiir  tiiattur  in  Noa.1-4. 


No.  4.— 
Vicksbarg. 


60.69 

7.95 

2.61 

.67 

.52 

.13 

.12 

8.96 

4.36 

1.17 

1.08 

1.14 

9.63 

.12 

.19 


99.54 


No.  5.— 

Near  Terre 

Haute. 


72.87 

11.25 

6.75 


.95 


.69 
1.06 

.39 
2.26 
4.24 


No.  6.— 

Near  Terre 

Haute. 


79.77 
9.95 
3.39 


.70 


.67 

.26 

1.08 

2.05 

2.55 


100. 44 


100. 42 


THE  lOWAN  LOESS.  165 


FOSSILS. 


From  the  time  of  the  earliest  recognition  of  the  loess  in  the  Mississippi 
Basin  the  presence  of  fossils  has  been  mentioned  as  a  peculiarity  of  the 
deposit.  These  fossils  are  present,  not  as  ingredients  of  a  mixture,  like  the 
wood  or  other  organic  remains  found  in  bowlder  clay  (whose  life  was  inde- 
pendent of  the  deposits  in  which  they  are  embedded),  but  as  a  fauna  repre- 
senting the  life  of  the  region  during  the  progress  of  the  accumulation  of 
the  deposit  and  dwelling  ixpon  it  or  in  it. 

The  loess  fossils  are  found  in  greatest  abundance  along  the  immediate 
borders  of  the  main  valleys  where  the  loess  attains  its  greatest  thickness, 
notably  along  the  Mississippi,  the  Illinois,  and  the  Wabash.  They  occur 
from  the  top  to  the  bottom  of  the  deposit  and  bear  clear  evidence  of  having 
lived  during  its  deposition.  Along  the  smaller  valleys  of  the  region  they 
are  rarely  found.  On  the  interfluvial  tracts  but  few  fossils  have  been  found 
at  a  distance  greater  than  5  miles  back  from  the  borders  of  the  main  valleys. 
The  most  notable  exception  is  in  the  thickened  loess  border  south  of  the 
Green  River  Basin,  where  the  loess  is  thought  to  have  been  deposited  along 
the  lowan  ice  front,  though  here  they  are  far  less  numerous  than  along  the 
main  valleys.  Fossils  are  also  distributed  more  widely  along  the  Sangamon 
than  along  other  tributaries  of  the  Illinois,  being  found  as  far  back  as  the 
vicinity  of  Springfield. 

.The  cause  for  the  scarcity  of  fossils  along  the  small  streams  and  in  the 
interfluvial  tracts  can  as  yet  scarcely  be  decided.  It  is  not  known  whether 
they  have  been  destroyed  there  by  subsequent  leaching  and  weathering  or 
were  never  present.  Professor  Shimek,  as  indicated  more  fully  below,  has 
found  that  in  eastern  Iowa  the  living  representatives  have  about  the  same 
distribution  in  relation  to  streams  as  those  embedded  in  the  loess,  and  he 
infers  that  the  loess  fossils  were  never  present  in  abundance  at  a  great 
distance  from  the  main  valleys. 

The  most  abundant  and  widely  distributed  fossils  are  mollusks,  of 
which  terrestrial  species  predominate  over  aquatic.  By  far  the  most  com- 
mon mollusk  is  Succinea  avara,  a  form  which  is  now  found  in  swampy 
places  as  a  rule,  but  which  occasionally  occurs  in  dry  situations.  Shimek 
regards. this  as  a  strictly  terrestrial  rather  than  a  semiaquatic  form.  The 
tables  given  below  serve  to  indicate  the  proportion  of  species  of  terrestrial 
and  aquatic  forms.     The  shells  of  a  few  unios  and  other  strictly  fluviatile 


166  THE  ILLINOIS  GLACIAL  LOBE. 

mollusks  have  been  reported  from  the  loess,  but  closer  investigation  tends 
to  render  doubtful  their  occurrence  in  unmodified  loess.  In  other  cases, 
notably  in  the  deposits  near  Freeport,  from  which  collections  have  been 
made  by  Hershey,  the  relation  to  the  loess  is  not  clearly  determined  and 
the  deposits  may  prove  to  be  entirely  independent  of  the  loess  deposition. 

Concerning  the  mammalian  remains  reported  from  the  loess,  it  is  neces- 
sary to  state  that  their  relation  to  the  loess  deposition  is,  in  most  if  not  in 
all  cases,  very  vaguely  determined.  The  remains  of  a  mammoth,  found 
near  Davenport,  and  reported  by  W.  H.  Pratt,  ^  were  apparently  from  near 
the  base  of  the  loess  and  just  above  the  Sangamon  soil,  which  is  there  rep- 
resented by  a  bed  of  peat  and  soil  3  feet  in  thickness.  Possibly  the  remains 
were  derived  from  the  Sangamon  soil  horizon  and  redeposited  in  the  basal 
portion  of  the  loess.  The  remains  of  a  deer  are  reported  by  Witter^  to 
have  been  found  in  the  loess  near  Muscatine.  A  fine  fragment  of  the  jaw 
of  a  mastodon  is  reported  by  Worthen^  to  have  been  found  just  above  the 
city  of  Alton,  Illinois,  beneath  30  feet  of  loess,  and  separated  from  the 
underlying-  limestone  by  2  or  3  feet  of  local  drift.  Worth  en  also  reports* 
the  occurrence  of  the  remains  of  extinct  mammalia  in  brown  clays  overly- 
ing the  limestones,  as  well  as  in  the  crevices  of  the  limestone  in  the  driftless 
region  of  northwestern  Illinois.  Whether  these  are  beneath  or  within  the 
loess  deposit  which  covers  that  region  has  not  been  ascertained. 

As  yet  the  molluscan  fossils  have  been  collected  and  specifically 
identified  in  but  a  few  localities  within  the  region  under  discussion.  Since 
there  is  some  variation  from  place  to  place,  the  identifications  of  each 
locality  are  represented.  Those  in  List  1,  from  Savanna,  Illinois,  repre- 
sent the  fauna  in  the  southern  portion  of  the  Driftless  Area.  In  addition 
to  these,  Helicodiscus  lineatus  Anth.  has  been  found  near  Galena  and  Lim- 
nopliysa  humilis  Say  has  been  found  on  the  heights  east  of  Prairie  du  Chien. 
These  are  thought  by  Salisbury  to  be  in  unmodified  loess,  and  are  separated 
from  a  list  of  fossils  found  in  the  terraces  of  streams  traversing  the  Driftless 
Area.^ 


'Proc.  Davenport  Acart.  Sci.,  Vol.  I,  1876,  pp.  96-99.  Also  Geol.  of  Iowa,  by  C.  A.  White,  Vol. 
I,  1870,  p.  119. 

'^Proc.  Iowa  Acad.  Sci.,  Vol.  1,  1880,  p.  16.  Also  Eleventh  Ann.  Kept.  U.  S.  Geol.  Snrvey, 
1890,  p.  471. 

»Geol.  of  lUiuois,  Vol.  I,  1866,  pp.  38  and  315. 

■■  Ibid.,  p.  39. 

'■•Sixth  Ann.  Rept.  U.  S.  (Jeol.  Snrvey,  pp.  28;")  iind  286. 


LOESS  FOSSILS.  167 

The  Davenport  fossils  are  apparently  from  the  unmodified  loess  along 
the  west  bluff  of  the  Mississippi,  as  are  also  those  from  Burlington,  Iowa. 
The  list  from  Moline,  Illinois,  is  from  specimens  gathered  on  the  level  upland 
lying  between  the  Rock  and  Mississippi  rivers.  A  loess-like  silt  carrying 
fossils  has  been  found  beneath  the  glacial  deposits  in  that  vicinity.  The 
fossils,  so  far  as  identified  in  this  lower  silt,  are  strikingly  similar  to  those 
found  in  the  surface  deposit. 

The  list  from  Muscatine,  Iowa,  contains,  in  addition  to  the  usual  loess 
fauna,  several  species  of  Unio.  Unfortunately  the  evidence  is  not  clear 
concerning  the  condition  of  the  bed  of  loess  in  which  these  Unio  shells  was 
found.  It  is  Professor  Witter's  present  opinion  that  the  loess  had  suffered 
some  disturbance,  thus  leaving  it  an  open  question  whether  the  shells  are  as 
ancient  as  that  deposit. 

The  fossils  noted  in  the  list  from  near  Freeport  are  stated  by  Hershey 
to  have  been  secured  from  under  a  bed  of  loess  in  a  blue-green  silt, 
separating  the  loess  from  the  underlying  gravel.  He  further  states  that  the 
gravel  is  made  up  in  part  of  erratics,  and  is,  therefore,  not  preglacial  in  age. 
This  gravel  and  the  overlying  silt  are  described  by  Hershey  under  the 
name  "Florencia  formation,"'  and  are  referred  to  an  interglacial  stage 
between  the  loess  deposition  (which  he  correlates  with  the  lowan  glaciation) 
and  a  preceding-  period  of  glaciation  now  provisionally  referred  to  the 
Illinoian.  It  is  stated  that  great  care  was  taken  in  securing  the  shells, 
because  it  was  early  recognized  that  a  fauna  of  very  similar  facies  occurs  in 
the  modern  alluvial  deposits  of  that  region.  It  is  also  stated  that  this  blue- 
green  silt  is  overlain  with  perfect  conformity  by  the  basal  member  of  the 
lowan  loess  series,  a  feature  which  leads  the  present  writer  to  question 
whether  it  should  be  separated  from  the  loess  series.  However,  the  striking 
contrast  between  the  fauna  of  this  deposit  and  that  usually  displayed  by  the 
loess  and  the  striking  similarity  to  the  alluvial  fauna  of  that  region,  should 
have  weight  in  determining  the  classification. 

Thte  list  from  Virginia,  Illinois,  is  made  up  entirely  of  a  collection  in 
the  office  of  Dr.  J.  F.  Snyder,  at  Vii'ginia,  who  also  made  the  identifications. 

'Amer.  Jour.  Sci.,  4th  series,  Vol.  IV,  1897,  pp.  90-98. 


168 


THE  ILLINOIS  GLACIAL  LOBE. 

Lists  of  loess  fossils. 


Names  heretofore  commonly  uaed. 

Names  in  Pilshry  and  Johnson's  check 
list  of  terrestrial  mollusks  for  1898. 

List  I.  From  Savanna,  Illinois.- 

Patula  Striatella  (Anth.)  Morse... 

Pyramidula    striatella    (Anth.) 

(Collected  by  R.  D.  Salisbury 

Pils. 

and  identified  by  R.  E.  Call.)a 

Patula    strigosa   var.  C  o  o  p  e  r  i 

Pyramidula    strigosa    iowensis 

W.  G.  B. 

Pils. 

Succinea  avara  Say . 

Succinea  avara  Say. 
Succinea  obliqua  Say. 
Succinea  avara  .Say. 
Succinea  obliqua  Say. 
Helicina  occulta  Say. 
Leuchocheila  fallax  (Say)  Try. 
Pyramidula    striatella   (Anth.) 

Succinea  obliqua  Say 

List  II.  From  Davenport,  Iowa. 
(Reported  by  W.  H.  Pratt.)  i 

Succinea  avara  Say 

Succinea  obliqua  Say 

Helicina  occulta  Say 

Pupa  fallax  Say 

Patula  striatella  (Anth.)  Morse... 

Pils. 

List  III.  From  Davenport,  Iowa. 
(Collected    by   J.  A.  Udden; 
identified  by  C.  T.  Simpson.) 

Succinea  avara  Say - 

Succinea  avara  Say. 
Succinea  luteola  Gld. 

Succinea  luteola  Gld 

Succinea  lineata  ?  W.  G.  B 

Succinea  grosvenorii  Lea. 

Ferussacia      subcylindrica      (L.) 

Cochlicopa     lubrica     (M  ii  1  1.) 

Biun. 

P.  &  J. 

Patula  striatella  (Anth.)  Morse  . .. 

Pyramidula    striatella    (Anth.) 
Pils. 

Helicodiscus  lineatus  (Say)  Morse. 

Helicodiscus      lineatus      (Say) 
Morse. 

Helicina  occulta  Say 

Helicina  occulta  Say. 
Sphyradium  edentulum  alticola 
(Inger.)  P.  <fej. 

Pupa  alticola  Inger ,,  ._.■ 

List  IV.  From  Muscatine,  Iowa. 

Patula  striatella  (Anth.)   Morse; 

Pyramidula    striatella   (Anth.) 

(Identified  by  F.  M.  Witter; 

also  Helix  striatella. 

Pils. 

revised  by  B.  Sliimek.)  c 

Zonites  fulvus  (Drap.)  Binn. ;  also 
Helix  fulva. 

Conulus  fulvus  (Drap.)  Miill. 

-Vallonia  pnlchella  (Miill.)  Binn.; 

'Valloiiiapulchella(Miill.)Binn.(? 

also  Helix  pulchella. 

Helicodiscus    lineatus    (Say) 

Helicodiscus  lineatus  (Say) 

Morse ;  also  Helix  lineata. 

Morse. 

Patula  strigosa  cooperi  W.  G.  B. ; 

Pyramidula    strigosa   iowensis 

also  Helix  cooperi. 

Pils. 

Pupa  peutodon  (Say)  Gld 

Bifidariapentodon  (Say)  Sterki. 
Bifidaria  corticaria  (Say)  Sterki. 
Pupa  muscorum  L. 
Sphyradium  edentulum  alticol.i 
(Inger.)P.  &  J. 

Pupa  corticaria  Say ,. 

Pupa  muscorum  L 

Pupa  alticola  Inger 

Succinea  avara  Say 

Succinea  avara  SAy. 

oPuhlishod  in  Sixth  Ann.  Eopt.  U.  S.  Gool.  Survey,  1885,  p.  285. 

6  Published  in  Proc.  Davenport  Acad.  Sci.,  1870,  pp.  00-99;  al.so  in  Eleventh  Ann.  Kept.  V.  S.  Geol.  Survey,  1890,  p.  471. 
c  Published  in  Proc.  Iowa  Acad.  Sci.,  1880,  p.  16;  also  in  Kleventh  Ann.  Kept.  U.  S.  Geol.  Survey,  1890,  p.  471. 
dSee  footnote  a  on  next  page. 


LOESS  FOSSILS. 
Lists  of  loess  fossils — Continued. 


169 


List  IV.  I^om  Mnscatine,  Iowa. 
(Identified  by  F.  M.  Witter ; 
revised  by  B.  Shimek.) — Con- 
tinued. 


List  V.  From  Burlington,  Iowa. 
(Collected  by  Frank  Leverett ; 
identified  by  C.  T.  Simpson.) 


List  VI.  From  near  Freeport, 
Illinois.  (Collected  by  Oscar 
Hersbey ;  identified  by  W.  H. 
Dall,)6.   1.  Terrestrial  species. 


Names  heretofore  commonly  used. 


Succinea  obliqua  Say 

Helicina  occulta  Say 

Limnaea  bumilis  Say 

Unio^ibenus  Lea 

Unio  ligamentinus  Lea 

XJnio  rectus  Lam 

Campeloma    subsolidum^  (Auth.) 

Call ;  also  Melantho  subsolida. 
Margaritana  confragosa  Say. 

Succinea  obliqua  Say 

Succinea  lineata  W.  6.  B 

Helicina  occulta  Say 

Patula  strigosa  cooperi  W.  G.  B. ; 

also  Pyramidula  strigosa. 
Pyramidula  striatella  Antb. ;  also 

Patula  striatella  (Anth.)  Morse. 
Pyramidula    perspectiva    (Say) 

Binn. 
Vallonia  costata  Miill. ;  also  Vallo- 

nia  pulchella  var.  costata. 

Vallonia  perspectiva  Sterki 

Zonitoides    arboreus    Say;    also 

Zonites  arboreus  (Say)  Binn. 
Zonites  radiatulus  Aid ;  also  Hya- 

llna  radiatula  Aid. 
Zonites  minusculus  Binn;   also 

Hyalina  minuscula  Binn. 
Zonites   indentatus   (Say)   Binn; 

also  Hyalina  indentata  Say. 
Patula  alternata  (Say)  Binu;   also 

Pyramidula  alternata  Say. 
Patula  striatella  (Antb.)    Morse; 

also  Pyramidula    st-riatella 

(Antb.)  Morse. 
Helicodiscus  liueatus  (Say)  Morse. 

Stenotrema  birsutum  (Say)  Try. ; 
also  Polygyra  hirsuta  Say. 


Names  inPilsbryand  Johnson's  check 
list  of  terrestrial  moUusks  for  1898. 


Succinea  obliqua  Say. 
Helicina  occulta  Say. 


Succinea  obliqua  Say. 
Succinea  grosvenorii  Lea. 
Helicina  occulta  Say. 
Pyramidula     strigosa   iowensis 

Pils. 
Pyramidula    striatella    (Anth.) 

Pils. 
Pyramidula  perspectiva    (Say) 

Pils. 
Vallonia  costata  Miill.  a 

Vallonia  perspectiva  Sterki. 
Zonitoides  arboreus  (Say)  P. <fc  J. 

Vitrea  bammouis  (Striim.) 

P.  &  J. 
Zonitoides    minusculus  (Binn.) 

P.  &J. 
Vitrea  indentata  (Say)  P.  &  J. 

Pyramidula    alternata     (S  a  y) 

Pils. 
Pyramidula    striatella   (Anth.) 

Pils. 

Helicodiscus      lineatus      (Say) 

Morse. 
Polygyra  hirsuta  (Say)  Pils. 


alt  is  no K^  difficult  to  ascertain  the  correctness  of  the  earlier  identifications  of  the  species  of  Vallonia.  The  species 
were  all  formerly  referred  to  T.  pulchella  or  to  T.  ptdchella  var.  costata,  hut  Dr.  Sterki's  investigations  have  brought  to 
light  a  greater  number  of  species  than  was  at  first  recognized.  Most  of  the  forms  formerly  called  T.  pulchella  from  the 
loess  west  of  the  Mississippi  are  T.  gracilicosta,  and  those  called  T.  pulchella  var.  costata  are  at  least  in  part  Y.  parvula 
Sterki.  This  difficulty  in  mating  the  identifications  does  not  in  any  manner  aflect  the  general  discussion,  as  all  the  species 
are  strictly  terrestrial  in  habit.     (Shimek.) 

6  Published  in  Am.  Jour.  Sci.,  4th  series,  Vol.  IV,  1897. 


170 


THE  ILLINOIS  GLACIAL  LOBE. 

Lists  of  loess  fossils — Continued. 


List  VI.  From  near  Freeport, 
Illinois.  (Collected  by  Oscar 
Hershey,  identified  by  W.  H. 
Dall.)  1.  Terrestrial  species — 
Continued. 


2.  Fluviatile  species  (gill-bear- 
ing univalves). 


3.  Fluviatile  bivalves  (some  oc- 
casionally in  ponds). 


4.  Pond    species    air-breathing 
(some  fluviatile). 


List  VII.  From  Moline,  Illinois. 
(Collected  by  J.  A.  Udden; 
identiiied  by  C.  T.  Simpson.) 


Names  heretofore  commonly  used. 


Names  in  Pilsbry  .ind  Jolinson's  clieck 
list  of  terrestrial  moUnskB  for  1898. 


Strobilops  virgo  Pils 

Pupa  contraclaSay 

Pupa  corticaria  Say 

Pupa  armifera  Say 

Pupa  holzinoeri  Sterki 

Vertigo  tridentata  Wolf 

Succinea  avara  Say 

Carychium  esiguum  (Say)  Gld  ... 

Carychium  exile  (?)  Pils 

Plenrocera  subulare  (Lea)  Try 

Campeloma  decisa  (Say)  Call 

Bythinella  tenuipes  (Coop.)  Binn. 

Amnicola  cincinniitiensis  Anth 

Amnicola  porata  (Say)  Hald 

Somatogyrus depressus  (Try.)  Gill. 

Valvata  tricarinata  Say 

Pisidium  compreasum  Prime 

Pisidium  cruciatum  Sterki 

Pisidium  fallax  Sterki 

Pisidium  punctiitnm  Sterki 

Pisidium  variabile  Prime 

Pisidium  virginicum  Gmel 

Pisidium  walkeri  Sterki 

Sphserium  Btamineum(Cou.)  Prime 
Sphiierium  striatiuum(Lam.)  Prime 

Sphaerium  simile  Say , 

Spha?rium  solidnlum  Prime 

Plauorbis  parvus  Say 

Pl.anorbis  bicarinatus  Say 

Pbysa  beterostropha  Say 

Segmentina  armigera  (Say)  .\d... 

Limuaea  bumilis  Say 

Aucylus  tardus  Say 

Ancy luB  rivularis  Say 

Ancylus  parallelus  Hald 

Siiccinea  avara  Say 

.Succinea  luteola  Gld 

Succinea  obli(]ua  Say 

Helicina  occulta  Say 

Patula  striatella  (Anth.)   Morse; 
al.so  Pyramidula  striatella. 


Strobilops  virgo  Pils. 
Bifidaria  contracta  (Say)  Sterki. 
Bifidaria  corticaria  ( Say)  Sterki . 
Bifidaria  armifera  (Say)  Sterki. 
Bifid,aria    holzingeri   (Sterki) 

Sterki. 
Vertigo  tridentata  Wolf. 
Succinea  avara  Say. 
Carychium  exiguum  (Say)  Gld. 
Carychium  exile  Pils. 


Succinea  avara  Say. 
Succinea  luteola  Gld. 
Succinea  obliqua  Say, 
lleliciua  occulta  Say. 
Pyramidula    striatella    (Anth.) 
Pils. 


LOESS  FOSSILS. 
Lists  of  loess  fossils — Continued. 


17] 


Kames  heretofore  commonly  used. 

Name3  in  Pilsbry  and  Johnson's  check 
liat  of  terrestrial  molluslis  for  1898. 

List  VII.  From  Mo 

ine^.  Illinois. 

Pupa  alticola  Inger 

Sphyradium  edentulum  alticola 
(Inger.)  P.  &  J. 

(Collected  by  J. 

A.  Udden; 

identified  by  C.T. 
Continued. 

Simpson.) — 

Pupa  muscorum  L 

Pupa  muscorum  L. 
Bifidaria pentodon  (Say)  St. 
Vallonia  pulchella  (Miill.)  Binn. 

Pupa  pentodon  ( Say)  Gld 

Vallonia  pulchella  (Mull.)  Binn.. . 

List  VIII.  From  Virginia,  Illi- 

Patula striatella   (Anth.)   Morse; 

Pyramidula    striatella    (Anth.) 

nois.     (Collected 

and  identi- 

also  Helix  striatella. 

Pils. 

fled  by  J.F.Snyder.) 

Helix  orbiculata?     Perhaps  Heli- 

? 

cina  orbiculata  or  Helicina  oc- 

culta Say. 

Macrocyclis  coucava  (Say)  Morse; 

Circinaria  concava  (Say)  P.  &  J, 

also  Helix  concava. 

Mesodon  clausa  (Say)  Try.;   also 

Polygyra  clausa  (Say)  Pils. 

Helix  clausa. 

Helix  solitaria?     Perhaps   Pyra- 

? 

midula  strigosa  iowensis  Pils. 

Stenotrema     monodon    (Eack.) 

Polygyra    monodon    (Rack. ) 

Morse;   also  Helix  monodon. 

Pils. 

Mesodon  multllineata  (Say)  Try; 

Polygyra     multiliueata    (Say) 

also  Helix  multiliueata. 

Pils. 

• 

Mesodon   penusylvanica    (Green) 

Polygyra  penusylvanica  (Green) 

Try ;  also  Helix  penusylvanica. 

Pils. 

Patula  alternata  (Say)  Binn. ;  also 

Pyramidula     alternata    (Say) 

Helix  alternata. 

Pils. 

Arionta  exarata  Pfeiff . ;  also  Helix 

Epiphragmophora        exarata 

exarata. 

(Pfeiff.)  P.  &  J. 

Succinea  obliqua  Say 

Succinea  obliqua  Say. 

Limnaea  hurailis  Say. 

Bulinus  dealbatus ;  probably  Buli- 

Bulimulus  dealbatus  ?. 

nu8  hypnorum  or  Bulimus  deal- 

batus. 

Professor  Shimek  has  furnished  the  following  notes  in  reference  to  the 
fossils  given  in  the  foregoing  lists. 

Of  the  foregoing  lists  I,  II,  III,  IV  (except  the  last  five  species),  V, 
and  VII  contain  typical  loess  fossils  and  may  be  considered  together.  The 
species  mentioned  are  the  following : 

1.  Conulus  fulvus  (Drap.)  Miill. 

2.  Helicodiscus  lineatus  (Say)  Morse. 

3.  Pyramidula  striatella  (Anth.)  Pils. 

4.  Pyramidula  strigosa  iowensis  Pils. 


172  THE  ILLINOIS  GLACIAL  LOBE. 

5.  Pyramidula  perspectiva  (Say)  Pils. 

C.  Yallouia  pulcbella  (Miill.)  Biun.' 

7.  Cochlicopa  lubiica  (Miill.)  P.  &  J. 

S.  Leucbochila  fallax  (Say)  Try. 

9.  Pupa  muscorum  L. 

10.  Bifidaria  corticaria  (Say)  St. 

11.  Bifidaria  arinifera  (Say)  St. 

12.  Bifidaria  pentodon  (Say)  St. 

13.  Sphyradium  edentulum  alticola  (luger.)  P.  &  J, 

14.  Succiuea  avara  Say. 

15.  Succinea  obliqua  Say. 

16.  Succinea  luteola  Gld. 

17.  Succinea  grosvenorii  Lea. 

18.  Heliciua  occulta  Say. 

19.  Limnaea  humilis  Say. 

Of  these  species  all  but  the  last  one  are  strictly  terrestrial  in  habit. 
One  species,  No.  5,  rare  in  northern  loess,  is  very  common  in  the  loess  of 
Mississippi.  The  last  species.  No.  19,  is  an  aquatic  pulmonate,  occurring  in 
pockets  or  restricted  parts  of  the  loess  as  though  deposited  at  the  edge  of 
a  pool  or  pond.^  As  for  the  last  five  species  in  List  IV  this  may  be  said: 
They  are  strictly  fluviatile.  There  are  reasons  for  believing,  however,  that 
they  did  not  come  from  unmodified  loess,^  and  morever  they  and  their 
relatives  have  thus  far  not  been  found  in  any  other  locality  except  in  what 
is  clearly  modified  loess.  Thei-e  still  remain  lists  VI  and  VIII  which  will 
be  discussed  separately. 

The  fossils  of  List  VI  are  in  all  probability  from  alluvium,  and  not 
ft-om  the  loess,  for  two  reasons — one  positive,  the  other  negative: 

1.  The  list  very  closely  resembles  lists  of  species  found  in  alluvium 
along  several  streams,  notably  along  Rock  River  near  its  mouth,  along  the 
Cedar  River  at  Cedar  Rapids  and  near  Mount  Vernon,  and  along-  the  Iowa 
near  Iowa  City.*  It  will  be  observed  that  the  species  in  this  list  are 
grouped  according  to  habit.  The  first  section  or  group  contains  the  terres- 
trial forms,  nearly  all  of  which  also  occur  in  the  loess.  All  row  live  on 
alluvial  bottom  lands  or  the  adjacent  hills,  and  their  shells  are  often  washed 
down  for  short  distances. 

2.  The  list  in  its  entirety  is  unlike  any  undoubted  loess  fauna  which 
has  been  reported  by  trustworthy  observers. 

'  Seo  footnote  a  on  p.  169. 

''See  (lispussioii  of  Liiiiiiira  by  Sliiinek,  in  Proc.  Iowa  Acad.  Sci.,  Vol.  V,  1898,  pp.  34,  .35. 
^  ProfosKor  Shimck  reached  this  couclnsion  after  a  eouversatiou  with  Professor  Witter. 
<Tlie  Rock  River  list  wiis  published  in  Iowa  University  Bulletin,  Vol.  II,  pp.  170  iind  171. 


LOESS  FOSSILS.  173 

The  shells  iu  List  VIII  are  for  the  most  part  terrestrial,  and  most  of 
them  occur  in  ordinary  loess  more  or  less  commonly.  The  list  is  striking- 
because  of  the  number  of  large  Helices  and  the  absence  of  small  forms, 
in  this  respect  being  more  like  the  southern  loess. 

It  is  probable  that  the  "■Helix  solitaria^^  of  the  list  is  our  Pyramidula 
strigosa  iowensis,  a  frequent  loess  fossil.  Helix  orbiculata  may  really  be 
Helicina  orhiculata,  a  species  much  like  our  Helicina  occulta,  to  which  the 
specimens  may  possibly  belong.  Helicina  orhiculata,  however,  is  common 
in  the  loess  of  Natchez.  Helix  exarata,  of  this  list,  is  a  west  coast  species, 
and  if  the  determination  is  correct  it  must  have  been  transported  a  great 
distance  overland.  It  is  out  of  place.  As  for  the  remaining  species,  all  the 
species  of  "Helix"  are  strictly  terrestrial.  Succinea  obliqua  and  Limnaea 
liumilis  have  already  been  discussed. 

Bulinus  dealhatus  should  be  either  Bulimus  dealbatus,  a  southern  terres- 
trial species,  or  it  is  Bulinus  hypnorum,  a  pond  snail  like  Limnsea  and  Physa 
in  habit.  Valvata  tricarinata  and  Vivipara  intertexta  are  fluviatile,  or  may 
be  found  in  ponds.  It  will  be  of  interest  to  ascertain  their  relation  to  the 
other  fauna  as  to  abundance  and  distribution.  On  the  whole  the  shells  are 
unlike  those  of  our  northern  loess,  but  differ  still  more  from  the  southern 
loess  fauna,  which,  so  far  as  I  have  been  able  to  determine,  is  absolutely 
without  aquatic  forms. 

"To  these  lists,"  writes  Professor  Shimek,  "I  can  add  but  few  names. 
From  Davenport  I  have  specimens  of  Limncea  liumilis ;  from  Muscatine 
Zonitoides  mimisculus  (Binn.)  P.  &  J.;  from  Moline  Limncea  liumilis  Say, 
and  Folygyra  clausa  Say." 

Since    the   foregoing    statement    was    written    Professor    Shimek    has 

received  several  collections  of  fossils  from  Prof  J.  A.  Udden,  and  reports 

upon  them  as  follows : 

From  Division  street,  Daveniiort,  Iowa,  near  base  of  loess.  Collected  by  Prof. 
J.  A.  Ucldeu: 

Helicina  occulta  Say. 

Succiuea  avara  Say. 

Spbyradium  edentulum  alticola  (Inger.)  P.  &  J. 

Pyramidula  striatella  (Antb.)  Pils. 

Bifldaria  peutodon  (Say)  Sterki. 

Limniea  palustris  Milll.  (fragment.) 

Limnaea  caperata  Say. 

SpbiBrium — fragment  of  a  valve. 


174  THE  ILLINOIS  GLACIAL  LOBE. 

The  last  three  species  in  this  list  are  pond  species. 

"  Prom  loess  iu  bluil'  above  Hershey  aveuue,  Muscatine,  Iowa."  (Prof.  J.  A. 
Uddeu's  note.) 

Helicina  occulta  Say. 

Polygyra  multiliueata  (Say)  Pils.     (Probably  this  species;  specimen  young.) 

Polygyra  monodon  (Eack.)  Pils. 

Strobilops  virgo  Pils. 

Bifiidaria  pentodon  (Say)  St. 

Pupa  muscorum  L. 

Coclilicopa  lubrica  (MilU.)  P.  &  J. 

Pyramidula  alteruata  (Say)  Pils. 

Pyramidula  perspectiva  (Say)  Pils. 

Pyramidula  striatella  (Anth.)  Pils. 

Succiuea  obliqua  Say. 

Succiuea  avara  Say. 

Succinea  ovalis  Gld. 

Limuaea  caperata  Say. 

Yalvata  siucera  Say. 

Succinea  ovalis,  of  which  one  specimen  was  submitted,  lives  on  mud 
flats,  etc.;  Limncea  caperata  and  Valvata  sincera  are  pond  species — the  latter 
now  for  the  first  time  reported  from  the  loess ;  all  the  others  are  terrestrial 

From  base  of  loess  iu  bluff  of  Mill  Creek,  about  5  miles  south  of  Milan,  Illinois, 
collected  by  Prof.  J.  A.  Udden : 
Succinea  avara  Say. 

Limufea  stagualis  L.     A  fragment,  probably  this  species. 
Limnrea  rel3exa  Say. 

Planorbis  albus  Miill.     Not  heretofore  reported. 
Plauorbis  parvus  Say. 
Valvata  tricariuata  Say. 
Valvata  sincera  Say. 
Pisidium .  Five  fragments  of  valves,  jirobably  belonging  to  two  species. 

With  the  exception  of  the  first,  all  of  these  are  pond  species. 

These  lists,  remarks  Shimek,  are  of  special  interest  because  of  the 
comparatively  large  number  of  pond  sjiecies  which  they  contain.  The 
presence  of  these  forms,  however,  does  not  strengthen  the  aqueous  theory 
of  loess  formation.  Both  the  distribution  of  these  aquatic  forms  in  the 
loess  and  their  habits  in  life  indicate  this.  They  do  not  represent  the  average 
loess-fauna  even  of  the  Mississippi  River,  but  occur  in  restricted  areas  and 
seem  to  have  been  collected  chieflj^  from  the  lower  part  of  the  loess.  In 
habits  these  forms  are  pond-inhabiting,  air  or  water  breathers,  which  do  not 
require  or  favor  large  bodies  of  water,  but  which  flourish  in  smaller  ponds. 


LOESS  FOSSILS.  175 

Their  presence  rather  only  serves  to  emphasize  my  contention  that  the 
fauna  of  the  loess  is  in  all  cases  very  similar  to  the  fauna  of  the  surface  in 
the  same  region.  Pond  species  are  more  abundant  and  of  greater  variety 
in  eastern  Iowa  and  Illinois,  especially  along  river  courses,  than  they  are 
westward.  Probably  during  the  deposition  of  the  loess  the  same  conditions 
existed,  and  the  agency  chiefly  concerned  in  the  work  of  deposition,  whether 
wind  or  water,  buried  more  of  these  aquatic  species  in  the  eastern  loess, 
simply  because  there  were  more  of  them,  proportionately,  upon  the  surface. 
The  following  quotation^  bears  upon  this  point: 

No  distinction  can  be  made  between  the  origin  of  eastern  and  western  loess. 
The  finer  quality  and  lesser  thickness  of  the  former  rather  suggest  that  there  had 
been  more  moisture  (i.  e.,  a  shorter  dry  period  during  each  year)  and  hence  less  dust; 
that  the  winds  were  less  violent,  and  that  there  were  greater  areas  completely  covered 
with  vegetation,  this  resulting  in  the  necessity  of  transporting  dust  much  greater 
distances,  which  would  therefore  be  finer. 

It  should  be  borne  in  mind  that  the  above  noted  diiierences  between  the  regions 
in  question  actually  exist  to-day.  There  is  more  rain — there  are  larger  areas  closely 
covered  with  vegetation,  and  less  violent  winds  prevail  in  eastern  Iowa  and  eastward — 
and  considering'  the  position  of  mountain  chains  and  seas,  the  same  differences  must 
have  existed  for  a  long  time.  That  they  did  exist,  during  the  deposition  of  the  loess, 
is  also  indicated  by  the  proportionately  somewhat  larger  number  of  species  in  the 
eastern  loess  which  prefer  or  require  moist  habitats.  But  the  fauna  of  the  eastern  or 
Mississippi  River  loess  is  essentially  a  terrestrial  fauna.  The  great  fluviatile  groups, 
now  everywhere  common  in  the  streams  of  eastern  Iowa,  are  wanting  in  the  loess,  and 
the  few  fossil  aquatic  species  are  such  as  to-day  prefer  ponds,  and  are  often  found 
even  in  those  which  dry  up  during  the  summer. 

In  addition  to  these  notes  furnished  by  Professor  Shimek,  a  few  remarks 
are  taken  from  his  discussion  of  the  loess  in  a  recent  paper  published  in 
Proceedings  of  the  Iowa  Academy  of  Sciences:^ 

The  majority  of  the  geologists  who  have  given  attention  to  the  loess  of  the 
Mississippi  Valley  have  ascribed  its  deposition  to  water  in  lakes  or  sluggish  streams 
Some  have  also  contended  that  this  occurred  in  a  glacial  climate,  or  at  least  in  a 
climate  much  colder  than  that  of  to-day  in  the  same  region. 

That  fresh  water  has  been  regarded  as  the  agent  of  deposition  is  due  in  no  small 
degree  to  the  belief  that  a  very  considerable  portion  of  the  species  and  individuals 
found  in  the  deposit  consist  of  aquatic  or  semiaquatic  forms,  although  the  fact  has 
long  been  recognized  that  terrestrial  species  prevail.  There  is,  however,  absolutely 
nothing  in  the  loess  fauna  to  indicate  that  the  loess  land  surfaces  were  more  moist,  or 
to  any  extent  more  widely  or  more  deeply  covered  with  waters,  than  are  the  surfaces 

'  Shimek:  Proc.  la.  Acad.  Sci.,  vol.  vi,  1898,  p.  110. 
::Proc.  Iowa  Acad.  Sei.  for  1897,  Vol.  V,  1898,  pp.  32-45. 


176  THE  ILLIKOIS  GLACIAL  LOBE. 

of  Iowa  and  Nebraska  to-day — the  evidence,  if  it  suggests  any  difference,  indicating 
rather  less  moisturt  than  is  found  iu  eastern  Iowa  at  the  preseut  time.  This  state- 
ment, which  can  not  be  too  strongly  emphasized,  is  based  upon  the  study  of  the  modern 
mollusks  of  Iowa  and  Nebraska  and  their  fossil  prototypes,  extending  over  a  period 
of  nearly  twenty  years.    *     *     * 

Moreover  the  molluscan  loess-fauna  of  any  region  is  ou  the  whole  like  the 
modern  fauna  of  the  same  regiou.  For  example,  Binney  reports  a  number  of  species 
from  the  "post- pliocene "  (evidently  the  loess)  of  the  lower  Mississippi  Valley,  of 
which  eleven  are  southerly  species,  and  all  now  live  iu  the  same  region.  Call  reports' 
fifteen  species  from  the  loess  of  Arkansas,  three  of  them  included  iu  the  southerly 
list,  and  all  belong  to  the  modern  molluscan  fauna  of  that  State.  The  same  is  true 
of  the  faunas  of  Iowa  and  Nebraska,  as  has  been  stated. 

This  does  not  indicate  transportation  from  a  distance.  It  is  interesting  and 
noticeable  that  for  the  most  part  the  species  of  the  loess  are  common  over  the  same 
region  now.  There  are  some  exceptions,  for  there  have  been  changes  no  doubt,  but 
these  changes,  as  indicated  by  the  distribution  of  the  shells,  are  no  greater  than  may 
now  be  observed  in  any  limited  region  in  the  course  of  a  few  years.  Species  are 
sometimes  disposed  to  appear,  disappear,  and  reappear  in  a  surprising  manner  in  a 
given  locality,  and  if  we  may  judge  from  the  vertical  distribution  of  the  fossil  shells, 
the  same  was  true  during  the  deposition  of  the  loess. 

The  horizontal  distribution  of  the  fossils  is  likewise  such  that  it  suggests  at  once 
that  they  are  deposited  in  situ. 

As  there  are  surface  areas  to-day  which  have  no  mollusks,  lying  in  close  proximity 
to  those  on  which  mollusks  are  abundant,  so  there  are  deposits  of  loess  without  fossi  s 
adjacent  to  those  which  are  fossiliferous.  As  the  lands,  high  or  low,  lying  adja- 
cent to  larger  streams  have  greater  numbers  of  mollusks  to  day  than  the  outlying- 
prairies,  so  the  loess  bordering  these  streams  is  usually  much  more  fossiliferous  than 
that  which  covers  more  remote  areas,  but  the  distribution  of  the  fossils  is  not  iu 
bands,  as  if  drifted,  but  is  similar  to  that  of  the  modern  specimens  at  the  surface.- 
Summing  up  the  evidence  of  the  fossils,  we  may  assert  that  it  points  to  conditions  not 
unlike  those  which  exist  to-day,  and  that  geologists  in  seeking  for  the  cause  aud 
manner  of  the  deposition  of  the  loess  must  give  up  the  assumption  of  widely  submerged 
areas  over  which  fossiliferous  loess  now  occurs,  and  of  a  cold  climate. 

MODE    OF    DEPOSITION. 

The  mode  of  deposition  of  the  loess  still  remains  one  of  the  most 
puzzling  problems  of  Pleistocene  geology.  Both  the  aeolian  and  aqueous 
hypothesis  have  strong  adherents  among  the  students  of  the  Mississippi 
Valley  portion  as  well  as  of  other  portions  of  this  formation.  The  students 
of  the  Mississippi  Valley  portion,  however,  all  grant  that  the  influence  of 
wind  has  been  important,  and  probably  all  would  concede  that  water  has 

'  Geol.  Survey  Ark.,  Vol.  IT,  pp.  49, 165,  aud  106. 

■'In  a  recfut  jiaper  Sbimek  li:is  discussed  more  fully  the  distributiou  of  loess  fossils:  Jonr.  Geol. 
Vol.  VII,  1899,  pp.  122-110.     Also  Proc.  Iowa  Acad.  Sci.,  Vol.  VI,  1898,  pp.  98-113. 


MODE  OF  DEPOSITION  OF  THE  LOESS.  177 

been  influential.  The  division  of  opinion,  therefore,  is  concerned  with  the 
relative  importance  of  wind  and  water  in  the  distribution  of  the  loess.  The 
question  of  the  influence  of  the  atmosphere  as  an  agent  of  erosion,  trans- 
portation, and  sedimentation  has  been  very  carefully  examined  by  Udden, 
with  the  result  of  showing  that  a  large  part  of  the  loess  may  have  been 
deposited  tlxrough  this  agency.^  In  a  recent  paper^  Chamberlin  has  dis- 
cussed the  peculiarities  of  distribution  and  considered  the  difficulties  attending 
the  application  of  either  hypothesis  to  the  entire  deposit.  The  distribution 
of  the  thickest  and  coarsest  loess  along  the  main  valleys,  with  its  great 
extent  down  the  Mississippi,  creates  a  strong  conviction  "that  the  deposition 
of  the  loess  was  in  some  vital  way  connected  with  the  great  streams  of  the 
region."  The  abrupt  border  of  the  loess  at  the  edge  of  the  lowan  drift  sheet 
both  in  Illinois  and  Iowa  gives  it  a  "more  or  less  direct  genetic  relationship 
with  the  ice."  The  graduation  of  loess  into  glacial  clays  "further  tends  to 
confirm  the  association  of  the  loess  with  glacial  action."  The  infliience  of 
glacial  action  is  also  shown  in  the  presence  of  silicates  which  are  decom- 
posable under  prolonged  weathering  and  of  calcium  and  magnesian  car- 
bonates, none  of  which  can  be  supposed  to  come  from  the  residuary  clays. 
An  illustration  from  the  Lower  Mississippi  Valley  is  given  which  strengthens 
this  inference: 

Above  the  Lafayette  gravels  and  below  the  loess  there  is  a  stratum  of  silt  which 
does  not  habitually  coutain  the  characteristic  silicate  particles  of  the  loess.  This 
stratum  has  been  by  most  observers  associated  with  the  loess,  but  it  is  separated 
from  it  by  a  soil  horizon,  as  abundantly  affirmed  by  the  observations  of  Salisbury  and 
the  writer.  On  the  other  hand,  it  graduates  more  or  less  freely  into  the  Lafayette 
sands  and  gravels.  The  stratum  is,  as  we  interpret  it,  the  last  deposit  of  the  Lafayette 
stage.  It  is  a  typical  finishing  deposit  succeeding  a  fluvial  sand  and  gi-avel.  Now 
this  has  special  significance  in  this  relationshii)  in  that  it  shows  that  in  the  stage 
closely  preceding  the  loess  deposition  the  Mississippi  did  not  lay  down  silts  of  the 
same  constitution  as  the  loess.  The  inference,  therefore,  is  that  the  loess  is  not  simply 
a  fluvial  silt  brought  down  from  the  surface  of  the  river  basin,  nor  common  wind  drift 
borne  into  it,  but  that  it  had  a  special  origin  connected  with  the  glacial  action  which 
was  com])etent  to  supply  precisely  the  kind  of  silt  of  which  the  loess  was  made. 

'  The  main  results  of  Uddeu's  studies  are  presented  in  the  following  ijapers:  "Erosion,  trans- 
portation, and  sedimentation  performed  by  the  atmosphere":  .Jour.  Geol.,  Vol.  II,  1894,  pp.  318-331. 
"Loess as  aland  deposit":  Bull.  Geol.  Soo.  Amer.,  Vol.  IX,  1897,  pp.  6-9.  "The  mechanical  composition 
of  wind  deposits,"  Augustana  Library  Publications,  No.  1,  1898.  Lutheran  Augustana  Book  Concern, 
Rock  Island,  Illinois. 

-Supplementary  hypothesis  respecting  the  origin  of  the  loess  of  the  Mississippi  Valley,  by  T.  C. 
Chamberlin  :  Jonrn.  Geol.,  Vol.  V,  1897,  pp.  795-802. 

MON  XXXVIII 12 


178  THE  ILLINOIS  GLACIAL  LOBE, 

The  leading  difficulties  cited  by  Chamberlin  as  attending  the  hypoth- 
esis that  the  loess  is  simply  an  outwash  of  glacial  griudings  distributed  by 
glacio-fluvial  waters,  are  its  vertical  distribution  and  the  presence  of  shells 
of  land  moUusks.  "  The  extreme  vertical  range  is  not  far  from  1,000  feet. 
The  range  within  a  score  of  miles  is  frequently  from  500  to  700  feet."  In 
its  interfluvial  phase  it  mantles  an  undulatorj^  surface  and  apparently 
reaches  a  greater  elevation  on  the  east  than  on  the  west  side  of  the 
main  valleys.  It  is  difficult  to  bring  its  boi'der  into  strict  accord  with  a 
horizontal  plain  as  required  by  the  lacustrine  and  marine  phases  of  the 
hypothesis,  or  even  into  a  consistent  gradient  as  required  by  the  fluvial 
phase,  without  an  arbitrary  warping  of  the  surface.  It  seems  also  extremely 
difficult  to  conceive  how  a  great  flood  which  had  the  ice  sheet  for  its  northern 
border  could  have  been  peopled  so  widely  with  land  mollusks.  In  view  of 
these  difficulties,  Chamberlin  proposes  to  divide  the  influence  of  wind  and 
water  as  follows.  He  adopts  the  glacio-fluvial  hypothesis  as  the  funda- 
mental explanation,  assuming,  (a)  the  presence  of  the  lowan  ice  at  the  chief 
stage  of  deposition;  (b)  a  very  low  slope  of  the  land  and  consequent  wide 
wandering  of  the  glacial  waters;  (c)  the  development  of  extensive  flats  over 
which  the  glacial  silts  were  spread;  (d)  great  periodic  extension  of  glacial 
waters  caused  by  (1)  periods  of  warm  weather  in  the  melting  season,  and 
(2)  by  warm  rains.  He  considers  it  probable  that  the  periodic  extensions 
of  the  floods  were  not  always  destructive  to  vegetation  over  the  flat  region, 
and  that  land  mollusks  and  other  animals  dependent  upon  the  vegetation 
may  have  found  temporary  retreat  from  the  flood  on  the  taller  vegetation. 
Upon  the  retreat  of  the  waters,  extensive  silt-covered  flats  would  become 
exposed  to  the  sweeping  influence  of  the  wind,  and  when  dried  the  silt 
would  be  borne  in  great  quantities  over  the  adjoining  iiplands. 

This  hypothesis  demands  an  accommodation  between  the  breadth  of 
the  fluvial  deposits  and  the  extent  and  massiveness  of  the  seolian  deposits, 
for  a  restriction  of  the  glacial  floods  to  narrow  channels  would  render  the 
sweeping  ground  for  the  winds  too  limited  in  area  to  supply-  material  for 
the  great  mantle  of  silt  found  on  the  uplands.  In  proportion  as  the  river 
work  is  narrowed  the  wind  work  is  expanded.  It  follows  that  the  c-Bolian 
factor  will  cut  away  its  own  ground  if  pushed  too  far.  It  is  further  urged 
that  the  ajolian  deposits  are  measured  not  by  the  quantity  of  silt  borne  by 
the  winds  and  lodged  on  the  surface,  but  by  the  difference  between  such 


MODE  OF  DEPOSITION  OF  THE  LOESS.  179 

lodgment  and  the  erosion  of  the  surface.  "  Erosion  is  ordinarily  more  than 
a  match  for  the  dust  accumulations.  The  conditions  must  have  been 
extraordinary  which  would  give  a  dust  deposition  sufficient  to  supply 
erosion  and  still  leave  such  a  large  residuum  as  the  loess  mantle  implies. 
The  unleached  and  imweathered  nature  of  the  body  of  the  loess  is  specially 
in  point  here.  These  considerations  warn  us  of  the  theoretical  danger  of 
too  greatly  circumscribing  the  fluvial  action."^ 

An  undue  extension  of  the  fluvial  hypothesis  is  thought  to  be  antago- 
nistic to  the  existence  of  molluscan  life  and  also  encounters  the  topograph- 
ical and  physical  difficulties  previously  urged.  In  conclusion  Chamberlin 
calls  attention  to  the  efforts  made  by  himself  and  colleagues  to  find  criteria 
of  discrimination  between  aqueous  and  seolian  loess,  and  remarks  that 
"  while  individual  types  of  both  deposits  are  not  difficult  to  find,  a  crite- 
rion or  series  of  criteria  of  general  applicability  which  shall  distinguish  the 
two  and  assign  to  each  its  appropriate  part  are  wanting." 

Turning  now  to  the  region  binder  discussion  in  order  to  test  the  appli- 
cability of  the  hypothesis  suggested  by  Chamberlin,  it  is  found  that  the 
variations  in  level  are  sufficiently  great  to  put  the  hypothesis  of  fliivial 
deposition  to  severe  tests,  though  they  are  not  so  conspicuous  as  in  border- 
ing districts  on  the  east  or  west.  The  district  covered  by  the  Illinois  glacial 
lobe  is  largely  embraced  between  the  levels  of  contours  lying  800  and  500 
feet  above  tide,  the  general  elevation  in  the  northern  portion  of  the  district 
being  about  800  feet  and  the  southern  jDOrtion  about  500  feet.  This  descent 
of  300  feet  in  passing  from  the  northern  to  the  southern  portion  of  the  State 
is  about  the  same  as  the  fall  of  the  Mississippi  River  along  its  western  borders. 
The  Mississippi  Valley,  however,  is  cut  to  an  average  depth  of  about  200  feet 
below  the  bordering  uplands.  A  small  portion  of  northern  Illinois  slightly 
exceeds  1,000  feet  and  portions  of  southeastern  Illinois  and  southwestern 
Indiana  fall  below  400  feet,  thus  giving  a  range  of  fully  600  feet  within 
the  limits  of  the  State,  aside  from  the  deepening  of  valleys  since  the  loess 
deposition.  The  most  conspicuous  abrupt  variation  in  elevation  of  loess- 
covered  districts  is  found  in  the  southern  end  of  the  State,  where,  as  above 
noted,  a  ridge  rises  300  feet  or  more  above  border  tracts.  A  few  conspicu- 
ous reliefs  occur  along  the  border  of  the  Mississippi  in  northwestern  Illinois 
and  in  the  portion  south  from  Quincy. 

'  For  a  partial  dissent  from  Chamberlin's  views  see  Udden:  Bull.  Geol.  Soc.  Amer.,  Vol.  IX,  1897, 
pp.  7-8 ;  also  Siiimek :  Proc.  Iowa  Acad.  Sci.,  Vol.  VI,  pp.  109-110,  and  Jour.  Geol.,  Vol.  VII,  1«99,  p.  135. 


180  THE  ILLINOIS  GLACIAL  LOBE. 

The  streams  of  southern  lUinois  are  flowing  in  broad  shallow  troughs 
in  which  a  rise  of  30  or  40  feet  would  cause  an  expansion  of  the  stream  to 
a  width  of  several  miles.  Such  is  notably  the  case  in  the  valleys  of  the 
Kaskaskia,  Big  Muddy,  Saline,  Little  Wabash,  Bon  Pas,  and  Embarras 
rivers.  The  same  is  ti-ue  of  the  lower  course  of  the  Wabash  and  of  a  por- 
tion of  White  River  below  Worthington  and  of  the  lower  course  of  East 
Wliite  River.  The  valleys  of  western  Illinois  and  southeastern  Iowa  were 
apparently,  at  the  time  of  the  loess  deposition,  cut  down  only  to  a  level 
60  to  100  feet  above  the  present  level  of  the  streams,  as  is  shown  by  the 
level  of  the  lowest  loess-capped  terraces.  This,  however,  is  50  to  100  feet 
below  neighboring  uplands.  A  rise  similar  to  that  which  would  cause 
extensive  flooding  in  southern  Illinois  would  not  carry  them  beyond  the 
limits  of  their  present  valley  bottoms.  Unless,  therefore,  a  rise  much 
greater  than  30  or  40  feet  be  assumed,  the  glacial  waters  would  have 
been  confined  to  the  immediate  channels  of  the  larger  streams,  and,  as 
urged  by  Chamberlin,  the  sweeping  ground  of  silt  for  the  winds  to  work 
VLpon  would  have  been  too  restricted  to  supply  the  great  mantle  of  silt 
covering  the  neighboring  uplands.  The  problem  here  puts  both  the 
■  fluvial  and  geolian  hypotheses  to  severe  test.  It  seems  necessary  to 
grant  a  rise  of  water  sufficient  to  overspread  the  neighboring  uplands  in 
order  to  afford  a  sufficient  sweeping  ground  to  supply  material  for  the 
portion  of  the  loess  mantle  found  along  the  divides.  In  southeastern  Iowa 
and  neighboring  portions  of  Illinois  and  Missouri  a  rise  of  100  to  150  feet 
would  be  necessary  to  cause  a  wide  expansion  of  the  glacial  streams. 
However,  with  the  assumed  low  altitude  of  the  loess-covered  region,  and 
resulting  low  gradient  of  the  streams,  a  depth  of  100  feet  of  water  over  the 
main  valleys  may  be  within  the  limits  of  probability.  A  rise  of  this 
amount  in  the  southern  Illinois  district  would  carry  the  waters  over  the 
greater  part  of  the  interfluvial  districts. 

The  evidence  relied  upon  to  demonstrate  the  agency  of  water  in  con- 
nection with  the  deposition  of  the  loess  and  associated  silts  is  the  presence 
of  material  too  coarse  to  have  been  transported  by  wind,  and  the  occur- 
rence of  water-laid  beds  of  sand,  silt,  or  coarser  material.  Such  evidence 
must  be  weighed  very  carefully  to  guard  against  including  irdqwsifcd 
material,  in  which  the  loess  and  the  coarser  material  have  been  brought 
down  from  higher  ground.  It  may  not  in  all  cases  be  possible  to  decide 
whether  there    has   been   a   redeposition.     But   the   present   writer  feels 


MODE  OF  DEPOSITION  OF  THE  LOESS.  181 

confident  that  he  has  seen  not  a  few  places  where  the  basal  portion  of 
unmodified  loess  carries  sand  and  coarser  material.  It  is  found  that 
on  the  borders  of  the  Mississippi  Valley  in  southeastern  Iowa,  and  also  for 
some  distance  back  from  the  stream,  pebbles  are  of  frequent  occurrence  in 
the  lower  portion  of  the  silts,  which  there  cap  the  Sangamon  soil  or  rest 
upon  the  slightly  eroded  surface  of  the  Illinoian  till.  Well-defined  bedding 
planes  also  appear,  especially  in  the  basal  portion  of  the  silt,  in  which  thin 
sand  partings  alternate  with  clay,  giving  an  appearance  similar  to  that 
found  in  the  fine  deposits  of  alluvium  on  the  bottoms  bordering  the  large 
streams.  These  pebbles  and  bedding  planes  have  been  found  in  Lee  and 
Des  Moines  counties,  Iowa,  at  an  elevation  of  slightly  more  than  700  feet 
above  tide,  or  fully  200  feet  above  the  present  level  of  the  Mississippi  River, 
and  about  130  feet  above  the  level  of  the  lowest  known  deposits  of  loess  in 
that  region.  The  breadth  of  the  glacial  waters  along-  the  Mississippi  Valley, 
must  have  been  25  to  50  miles  if  the  deposits  just  noted  mark  the  highest 
level;  possibly  a  still  higher  level  was  reached.  Whether  there  was  clear 
evidence  of  the  spreading  of  glacial  waters  over  the  entire  divide  between 
the  Avatersheds  of  the  Mississippi  and  Illinois,  can  not  be  stated.  But  the 
known  extent  of  the  glacial  waters  seems  adequate  to  have  furnished  material 
for  mantling  the  higher  portions  of  this  divide  by  seolian  agencies.  Exami- 
nations in  southern  Illinois  have  brought  to  light  the  general  prevalence  of 
small  pebbles  in  the  silt  which  covers  that  district.  There  seems  little  ques- 
tion that  from  the  base  of  the  elevated  ridge  in  southern  Illinois  northward, 
as  far  as  these  silts  are  exposed,  outside  the  Wisconsin  drift,  the  aqueous 
agencies  have  been  influential  and  were  probably  the  chief  agencies  of 
deposition. 

To  what  extent  the  elevated  ridge  in  southern  Illinois  was  covered  by 
glacial  waters  has  not  been  determined.  Possibly  a  portion  of  the  silt  which 
caps  this  ridge  was  deposited  while  the  Illinoian  ice  rested  upon  its  northern 
slope,  though  no  positive  evidence  of  such  deposition  has  been  noted. 

The  extent  of  the  glacial  waters  on  the  borders  of  the  Mississippi  in 
northwestern  Illinois  and  northeastern  Iowa  is  also  undetermined.  Mr.  Oscar 
Hershey  has  found  water-bedded  silt  along  the  Pecatonica  River  and  Yel- 
low Creek  valleys,  in  Stephenson  County,  Illinois,  which  he  thinks  imme- 
diately preceded  the  loess  in  deposition.  This  silt  is  confined  to  low  levels 
along  the  valleys  rising  scarcely  above  the  present  water  level.  The  full 
extent  of  water  action  in  this  basin  has  not  been  determined.     It  seems 


182  THE  ILLINOIS  GLACIAL  LOBE. 

probable  that  the  loess  on  the  immediate  borders  of  the  Pecatonica  lobe  is 
water-bedded,  even  at  levels  800  feet  or  more  above  tide.  Possibly  this 
lobe  held  a  body  of  water  in  the  Pecatonica  Basin  at  a  level  nearly  as  high 
as  the  bordering  uplands  (900  feet  above  tide). 

The  relation  of  the  bluff  loess  to  the  iipland  loess  is  a  question  of  prime 
importance.  It  has  been  commonly  assumed  that  deposition  was  completed 
at  nearly  the  same  date  on  the  uplands  and  on  the  valley  borders,  and  that 
the  difference  in  porosity  is  due  to  a  greater  strength  of  the  current  along 
the  line  of  the  main  valle3^s.  It  is  probably  true  that  the  main  valleys 
were  the  line  of  strongest  ciuTent  during  the  deposition  of  the  upland  loess, 
and  possibly  the  deposition  of  the  bluff  loess  was  completed  at  a  date  nearly 
as  early  as  that  of  the  water-laid  deposits  on  the  bordering  uplands.  There 
is  thought,  however,  to  be  evidence  pointing  to  a  continuance  of  loess  depo- 
sition along  the  main  valleys  after  deposition  had  practically  ceased  on  the 
uplands.  The  evidence  referred  to  consists  of  an  excessive  filling  by  loess 
of  the  valley  recesses  and  lower  courses  of  tributaries,  such  as  seem  explain- 
able as  a  result  of  transportation  down  the  valley  after  the  flooding  of  the 
uplands  had  ceased.  Accumulations  of  this  class  are  especially  noticeable 
on  the  lower  course  of  the  Wabash  and  Ohio  rivers,  and  they  are  found  to 
some  extent  along  the  Illinois  and  Mississippi.  Mr.  H.  F.  Bain  also  reports 
that  the  same  feature  is  noticeable  along  the  borders  of  the  Missouri  River 
in  western  lowa.^  It  is  found  that  the  blocking  is  most  conspiciious  on  the 
east  side  of  the  valleys,  a  feature  which  sug-gests  that  wind  action  has  been 
effective  in  causing  the  blocking  of  the  mouths  of  tributaries,  for  the  pre- 
vailing winds  are  from  the  west.  Upon  the  retirement  of  the  glacial  waters 
to  the  limits  of  the  main  valleys  or  to  their  immediate  borders  the  material 
available  for  transportation  would  be  chiefly  loess,  and  the  loess  would  have 
had  little  opportunity  to  become  leached.  We  may  suppose,  therefore,  that 
a  deposition  of  unleached  loess  continued  until  tlie  glacial  waters  had  retired 
completely  and  the  streams  were  fed  only  by  the  rainfall  of  the  region. 
This  may  have  been  maintained  for  some  time  after  the  disappearance  of 
the  lowan  ice  sheet,  though  it  appears  not  to  have  continued  sufficiently  long 
to  have  overlapped  to  any  marked  degree  the  valley  excavation  which 
followed  the  loess  deposition. 

As  noted  above,  the  fossils  of  the  loess  are  confined  largely  to  the 


'  DiscUBsidii  111  Twelfth  Amuial  Jleetiiig  hnvii  Acad.  Sci.,  lU'c,  18i'7. 


MODE  OF  DEPOSITION  OF  THE  LOESS.  183 

immediate  borders  of  the  valleys,  i.  e.,  to  the  portion  of  the  loess  which 
may  have  been  deposited  after  the  retirement  of  the  floods  from  the  uplands. 
The  most  notable  exceptions  are  their  occurrence  in  the  paha  ridges  and  in 
the  heavy  loess  bordering  the  lobes  of  lowan  ice  in  eastern  Iowa  and  west- 
ern Illinois.  It  seems  difficult  to  refer  the  latter  deposits  to  a  much  later 
date  than  the  culmination  of  the  glacial  flood,  though  it  is  possible  that  the 
filling  was  continued  along  the  immediate  borders  of  the  ice  lobes  to  a  time 
considerably  later  than  the  culminating  stage  of  the  flood  and  even  to  a 
time  when  vegetation  had  obtained  a  foothold  on  the  neighboring  silt- 
covered  tracts.  If  the  deposition  of  the  portion  of  the  loess  containing 
fossils  can  be  shown  to  have  continued  down  to  a  time  when  the  floods  had 
retired  to  the  limits  of  the  main  valleys,  objections  drawn  from  the  char- 
acter of  the  fossils  against  the  aqueous  deposition  of  loess  on  the  bordering 
uplands  would  be  fully  met.  It  becomes,  therefore,  a  matter  of  much 
importance  to  settle  definitely  the  age  of  the  fossil-bearing  deposits  with 
reference  to  the  culminating  stage  of  the  glacial  water. 

Before  leaving  this  subject  a  few  remarks  seem  in  place  concerning  the 
deposits  of  loess  which  are  evidently  seolian.  The  first  aeolian  loess  to  attract 
the  writer's  attention,  as  such,  is  found  along  the  east  border  of  the  Missis- 
sippi Valley  opposite  Burlington,  Iowa.  The  loess  there  has  accumulated 
in  dunes  which  give  it  a  relief  of  25  to  75  feet  above  the  neighboring 
uplands  on  the  east.  When  viewed  from  the  uplands  it  a23pears  as  a  bil- 
lowy ridge  fringing  the  river  bluff.  This  loess  is  found  to  be  fossiliferous 
and  calcareous,  and  were  it  not  for  its  topography  and  for  a  slight  admix- 
ture of  sand  recently  drifted  to  it  from  the  broad  bottoms  of  the  Mississippi 
River  it  would  present  no  essential  difference  from  the  flat-surfaced  portions 
of  the  loess  along  the  borders  of  the  river  elsewhere.  A  similar  relief  of 
the  loess  on  the  brow  of  the  bluft',  above  uplands  to  the  east,  has  been  since 
noted  just  beloAV  Alton,  Illinois.  It  also  occurs  to  a  slight  degree  on  the 
east  border  of  the  Mississippi  above  Burlington.  It  is  now  known  that  the 
general  thickness  of  the  loess  on  the  east  side  of  the  Mississippi  Valley,  from 
the  Driftless  Area  southward  through  the  entire  length  of  the  State  of  Illi- 
nois, is  markedly  greater  than  on  the  west  side  of  the  valley  in  Iowa  and 
Missouri,  probably  twice  as  great.  A  similar  difference  is  found  on  the 
east  and  west  sides  of  the  Wabash  Valley;  on  the  Illinois  the  difference  is 
not  so  marked.     It  is  thought  that  this  extra  thickness  of  the  loess  on  the 


184  THE  ILLINOIS  GLAOIAL  LOBE. 

east  borders  of  the  valleys  is  the  result  of  seolian  agencies,  for  there  seems 
no  reason  to  suppose  that  the  glacial  waters,  while  overspreading  the  uplands 
on  the  borders  of  the  valleys,  would  have  deposited  an  excessive  amount 
of  sediment  on  the  east  side.  Whether  the  aeolian  action  is  to  be  measured 
simply  by  the  excess  of  the  accumulation  on  the  east  bluff  or  should  be 
made  to  include  a  portion  on  both  bluffs  of  the  stream  is  not  as  yet  mani- 
fest. The  west  winds  may  have  carried  material  from  one  valley  across  to 
its  neig'hbor  where  valleys  approach  closely,  as  in  the  case  of  the  Illinois 
and  Mississippi,  in  Calhoun  County,  Illinois,  where  seolian  loess  appeal's  to 
have  covered  the  entire  interval.  The  calcareousness  of  the  seolian  loess  is 
significant  and  has  an  important  bearing  upon  the  determination  of  the 
source  of  supply  and  the  date  of  deposition.  The  supply  can  hardly  have 
been  derived  fi-om  the  great  western  plains,  where  the  material  available 
for  wind  transportation  is  largely  leached  of  its  calcareous  iugi-edients.  It 
can  not  be  referred  to  a  much  later  date  than  the  close  of  the  lowau  stage 
of  glaciation,  since  leaching  would  have  rendered  the  sui-face  portion  of  the 
silts  noncalcareous.  It  can  not  be  referred  to  a  much  earlier  date,  for  it  is 
separated  from  the  Illinoian  drift  sheet  by  the  Sangamon  soil  and  weathered 
zone.  As  urged  by  Chamberlin,  the  seolian  deposition  appears  closely 
connected  with  glacial  and  fluvial  deposition. 


CHAPTER    VTII. 

THE    PEORIAN    SOIL    AND    WEATHERED    ZONE    (TORONTO 

FORMATION!). 

GB^STERAL  STATEMENT. 

The  interval  between  the  lowan  and  Wisconsin  stage  of  glaciation  has 
been  provisionally  named  Toronto  by  Chamberlin  because  of  excellent 
exposures  of  interglacial  fossiliferous  beds  along  the  Don  Valley  in  Toronto, 
Ontario,  which  may  prove  to  have  this  age.^  Chamberlin  remarks  in  con- 
nection with  the  introduction  of  this  name  that  the  grounds  for  this  corre- 
lation are  not  very  strong  and  that  further  investigation  may  show  them  to 
be  erroneous.  He  further  remarks  that  "whether  the  beds  on  the  Don 
belong  to  the  horizon  suggested  or  not,  it  is  certain  that  vegetal  beds  were 
formed  in  the  interval  of  the  retreat  between  the  formation  of  the  lowan 
till  and  the  formation  of  the  Wisconsin  till,  and  some  of  these  less  well 
developed  and  less  known  deposits  must  be  looked  to  as  a  type  of  this 
interglacial  horizon  if  the  Toronto  beds  prove  unavailable." 

In  view  of  the  uncertainty  attached  to  this  correlation  it  seems  advis- 
able to  employ  for  the  present  a  substitutional  name  (Peorian)  which  is 
known  to  be  applicable  to  the  interval  between  the  lowan  and  the  early 
Wisconsin.  In  case  the  correlation  suggested  by  Chamberlin  is  demon- 
strated to  be  correct,  the  name  Toronto  has  precedence. 

SOIL  AND  PEAT  BETWEEN  THE  lOWAN  AND  WISCONSIN  DRIFT  SHEETS. 

Extensive  deposits  of  muck  and  peat  occur  at  the  base  of  the  Wis- 
consin drift  in  northern  Illinois,  notably  in  McHenry,  Kane,  Dekalb, 
Lasalle,   and  Bureau   counties,  which  are  in  all  probability  immediately 

''Classification  of  American  glacial  deposits,  by  T.  C.  Chamberlin :  .Jour.  Geology,  Vol.  Ill,  1895, 
pp.  270-277. 

185 


186  THE  ILLESTOIS  GLACIAL  LOBE. 

underlain,  in  some  cases  at  least,  by  lowan  drift.  In  central  and  eastern 
Illinois  the  soil  is  in  places  underlain  by  a  fossiliferous  silt,  refen-ed  with 
some  confidence  to  the  lowan  loess.  In  eastern  Illinois,  as  noted  above, 
the  lowan  till  may  be  present.  This  soil  horizon,  together  with  lower  soil 
horizons,  was  discussed  by  the  writer  in  a  paper  presented  at  the  Cleveland 
meeting  of  the  American  Association  for  the  Advancement  of  Science.^ 
At  that  time  the  separation  of  the  lowan  sheet  from  the  Illinoian  had  not 
been  made  and  all  the  soils  were  refen-ed  to  a  single  horizon.  The  later 
developments  have  led  the  writer  to  separate  the  soils  found  at  or  slightly 
below  the  base  of  the  Wisconsin  drift  into  two  classes,  one  class  being 
thrown  into  the  Sangamon  stage,  while  the  other  is  thrown  into  the  stage 
under  discussion.  It  is  not  possible  in  all  cases  to  decide  to  which  class  a 
buried  soil  should  be  referred,  for  in  some  cases  its  existence  is  known  only 
through  well  records.  Such  separations  as  have  been  made  may  be  foimd 
in  the  discussion  of  the  wells  of  Illinois,  in  the  latter  part  of  this  report, 
and  in  the  discussion  of  the  lowan  till  above. 

In  selecting  a  name  for  the  horizon  the  ideal  locality  would  be  one  in 
which  the  earliest  sheet  of  Wisconsin  till  overlies  the  lowan  till.  In  the 
vicinity  of  Marengo,  in  McHenry  County,  a  black  muck  has  been  found  at 
the  base  of  the  Wisconsin  drift,  and  it  apparentlv  rests  on  lowan  till.  This 
might  be  taken  as  a  type  locality  were  it  not  that  the  Wisconsin  drift  at 
that  point  may  not  include  the  Shelbyville  or  earliest  Wisconsin  sheet  of 
till.  The  same  objection  may  be  urged  against  bmied  soils  found  in  Kane, 
Dekalb,  Lasalle,  and  Bureau  counties,  for  in  all  these  counties  the  outer 
Wisconsin  ridge  appears  to  be  the  Bloomington  moraine,  and  the  limits  of 
the  Shelbyville  may  be  to  the  east  of  this  ridge.  It  has  seemed  advisable, 
therefore,  in  the  selection  of  a  type  locality  to  pass  to  central  Illinois,  where 
the  Shelbyville  sheet  extends  beyond  the  later  sheets  of  Wisconsin  di'ift. 
This  unfortunately  cames  us  beyond  the  lowan  till,  but  the  loess  whose 
deposition  seems  to  be  connected  closely  with  the  lowan  glaciation  is  there 
well  developed.  The  interval  between  the  loess  and  Shelbyville  till  sheet 
probably  marks,  as  well,  the  time  between  the  culmination  of  the  lowan 
and  Wisconsin  glaciations,  as  if  taken  where  the  Shelbyville  sheet  overlies 
lowan  till. 


'  For  .abstract  of  paper,  see  Proo.  Am.  Assoc.  Adv.  Sci.,  Thirty-seventh  Meeting,  1888,  pp.  183, 184. 


THE  PEORIA^r  SOIL  AND  WEATHERED  ZONE.  187 

LEACHED   LOESS  BENEATH  THE  WISCONSI]?f  DRIFT. 

The  loess  has  been  traced  back  ha  valley  exposures  several  miles 
beneath  the  Shelbyville  till  sheet  in  northern  Tazewell  County,  Illinois, 
and  beneath  the  combined  Shelbyville  and  Bloomington  sheets  in  Woodford 
and  Bureau  counties.  Farther  south  it  has  been  recognized  in  well  sections 
in  southern  Tazewell,  northeastern  Logan,  western  Dewitt,  southern  Macon, 
and  western  Sullivan  counties,  Illinois.  The  phase  known  as  white  clay 
has  been  traced  several  miles  up  the  Kaskaskia  and  Embarras  valleys,  in 
Shelby  and  Coles  counties,  beneath  the  Shelbyville  till  sheet. 

Of  the  several  exposures  in  which  the  loess  appears  below  the  Shelby- 
ville drift,  those  east  of  Peoria,  in  northern  Tazewell  County,  are  the  best 
displayed.  Decisive  evidence  is  also  found  at  these  exposures  of  an  interval 
of  some  length  between  the  deposition  of  the  loess  and  the  deposition  of 
the  overlying  Shelbyville  till  sheet.  In  view  of  these  conditions  in  the 
vicinity  of  the  city  of  Peoria,  it  has  seemed  appropriate  to  apply  the  name 
Peorian  to  the  interval  between  the  lowan  loess  and  the  Shelbyville  till  sheet. 

In  exposures  along  the  Toledo,  Peoria  and  Western  Railway  east  of 
Peoria,  and  also  on  the  east  bluiF  of  the  Illinois  opposite  that  city,  the 
Shelbyville  sheet  is  tmderlain  by  a  bed  of  fossiliferous  loess,  similar  to  that 
found  on  the  surface  of  the  Illiuoian  outside  the  limits  of  the  Shelbyville 
drift  sheet,  both  in  textui'e  and  in  age.  The  loess  is  8  to  12  feet  in  thick- 
ness, or  about  the  same  as  on  the  uplands  outside  the  Shelbyville  sheet. 
It  occurs  at  a  corresponding  elevation  of  about  200  feet  above  the  Illinois 
River.  Beneath  it  there  is  exposed  fully  100  feet  of  the  older  or  Illinoian 
drift  sheet.  In  places  the  upper  pai't  of  the  loess  to  a  depth  of  2  or  3  feet 
presents  a  darker  brown  color  than  the  lower  portion  and  is  partially  leached 
of  its  calcareous  ingredients.  In  one  place,  about  3  miles  west  of  Wash- 
ington, a  thin  soil  carrying  fragments  of  wood  is  exposed  in  the  bluff  of 
Farm  Creek  at  the  top  of  the  loess.  These  exposures  east  of  Peoria  were 
thought  to  afford  excellent  opportunities  for  a  comparison  of  the  Peorian 
and  Sangamon  weathered  zones,  and  were  consequently  visited  in  May^ 
1898,  by  a  party  of  geologists  in  company  with  the  writer,  including  Profs. 
T.  C.  Chamberlin,  Samuel  Calvin,  J.  A.  Udden,  Dr.  S.  W.  Beyer,  and  Dr. 
H.  F.  Bain.  It  seenied  to  all  present  that  the  Sangamon  weathered  zone 
calls  for  more  time  in  its  formation  than  appears  to  have  been  required  in 


188  THE  ILLINOIS  GLACIAL  LOBE. 

the  development  of  the  Peorian  zone  as  there  displayed.  It  is  possible, 
however,  that  other  lines  of  evidence  next  to  be  considered  maj?^  call  for  a 
period  of  greater  length  between  the  lowan  and  Wisconsin  stages  of  glaci- 
ation  than  these  exposures  of  the  Peorian  weathered  zone  seem  to  require. 

lOWAK    OUTLIlSrE    COMPARED    WITH    SUCCEEDING    AND    PRECEDING 

GLACIATIONS. 

Evidence  of  an  interval  between  the  lowan  and  early  Wisconsin  g-laci- 
ations  is  found  in  the  great  dissimilarity  in  the  outline  of  the  two  ice  sheets. 
The  outline  is  more  out  of  harmony,  both  with  the  early  Wisconsin  and 
the  Illiuoian,  than  the  outline  of  these  sheets  with  each  other.  The  srreat 
extension  toward  the  south  border  of  the  Driftless  Area,  both  in  the  Iowa 
and  Illinois  lobes  of  lowan  ice,  is  singularly  out  of  harmony  with  both 
succeeding  and  preceding  glaciations.  The  shifting  of  lobes  involved  in 
the  change  from  the  lowan  to  the  early  Wisconsin  can  scarcely  be  assumed 
to  have  occurred  in  a  brief  interval.  The  moraine-forming  habit  of  the 
Wisconsin  and  absence  of  distinct  morainic  belts  in  the  lowan  also  implies 
a  change  in  glacial  conditions  that  can  hardly  have  taken  place  suddenly. 

CHANGE  IN  ATTITUDE  OF  THE  IjAND. 

Evidence  of  an  interval  between  the  deposition  of  the  lowan  loess  and 
associated  silts,  and  that  of  the  Shelbyville  till,  is  found  in  a  change  in  the 
attitude  of  the  land,  which  resulted  in  a  marked  deepening  of  the  valleys. 
There  appears  to  have  been  a  greater  depth  of  excavation  during  the 
Peorian  stage  than  during  the  Sangamon.  The  breadth  of  excavation, 
however,  amounted  to  but  a  fraction  of  that  in  the  Sangamon  stage. 

LENGTH  OF  THE  PEORIAN  STAGE. 

The  amount  of  change  in  altitude  can  as  yet  scarcely  be  even  conjec- 
tured, much  less  demonstrated,  but  its  effects  on  the  drainage  are  such  as  to 
support  the  view  that  it  denotes  a  time  interval  of  considerable  length,  a 
view  which  is  also  supported  by  the  work  accomplished  in  deepening  the 
valleys.  Comparing  the  w(~)rk  with  substages  of  the  Wisconsin  it  appears 
that  the  interval  may  not  greatly  exceed  that  between  the  Shelbyville  and 
Bloomington  ice  advances.     The  Shelbyville  sheet  had  become  channeled 


THE  TOBONTO  FORMATION.  189 

by  streams  prior  to  the  Bloomiiigton  substage  of  glaciation  to  nearly  as 
marked  a  degree  as  the.  channeling  below  the  level  of  the  loess  effected  in 
the  Peorian  stage  of  deglaciation.  There  was  also  a  marked  increase  in  the 
stream  gradients,  the  Bloomington  drift  sheet  being  accompanied  by  a  much 
more  vigorous  gravel  outwash  than  that  which  accompanies  the  Shelby- 
ville  sheet.  In  the  writer's  opinion  it  is  questionable  if  the  interval  between 
the  lowan  and  early  Wisconsin  invasions  covers  more  than  a  small  fraction 
of  the  time  occupied  by  those  between  the  lowan  and  lUinoian  and  between 
the  lUinoian  and  Kansan.  The  union  of  the  several  lines  of  evidence  just 
cited  would  seem  to  support  the  view  that  it  is  longer  than  the  interglacial 
substag-es  of  the  Wisconsin.  The  view  of  a  brief  interval  between  the 
lowan  and  Wisconsin,  however,  meets  a  strong  objection  in  the  supposed 
attendant  deposits  at  Toronto. 

THE  TOROKTO  FORMATIO^ST. 

Turning  to  the  Toronto  formation  it  is  found  that  a  fossiliferous  silt 
occupying  a  hoi'izon  between  bowldery  glacial  clays  has  a  fauna  and  flora 
which  denote  a  climate  fully  as  mild  as  that  which  at  present  characterizes 
that  region.^  In  discussing  this  formation  Dr.  A.  P.  Coleman  remarks  that 
unless  the  Labrador  gathering-  ground  is  shown  to  have  stood  much  higher 
than  at  present,  it  can  scarcely  be  supposed  that  a  widespread  sheet  of  ice 
was  maintained  there  while  oaks  and  maples  and  pawpaws  flourished  on 
the  land  and  Mississippi  unios  in  the  waters,  within  400  to  600  miles  to  the 
southwest.  In  the  absence  of  any  evidence  of  such  uplift,  he  concludes  that 
the  ice  fields  were  completely  melted  during  this  interglacial  epoch. 

The  extent  of  deglaciation  suggested  by  these  beds,  so  far  as  space  is 
concerned,  can  scarcely  be  supposed  to  have  been  exceeded  either  by  the 
Sangamon  or  the  Yarmouth  stage  of  deglaciation.  The  Toronto  beds  con- 
stitute probably  the  most  decisive  evidence  yet  brought  forward  in  sujDport 
of  an  extensive  deglaciation  within  the  Glacial  period.  The  time  involved 
may  reasonably  be  supposed  to  cover  a  portion  of  the  Glacial  period  by  no 
means  small.     Its  rank  should  be  as  high  as  that  of  any  of  the  interglacial 

'  See  descriptions  by  Dr.  A.  P.  Coleman  and  Prof.  D.  P.  Penhallow:  Am.  Geologist,  Feb  ,  1894, 
Vol.  XIII,  pp.  85-95.  See  also  additional  interpretation  by  Dr.  Coleman :  Jour.  Geol.,  Vol.  Ill,  pp.  274, 
622-645.  For  description  of  fossiliferous  beds  at  Scarborough  Heights  aud  other  localities  near 
Toronto,  by  Dr.  George  J.  Hinde,  see  .Tour.  Canadian  Inst ,  April,  1877. 


190  THE  ILLINOIS  GLACIAL  LOBE. 

stages,  even  if  less  prolonged  thau  some  of  the  earlier  stages  of  deglacia- 
tion.  Should  it  be  proved  to  represent  the  interval  between  the  lowan  and 
Wisconsin  deposits,  as  now  seems  probable,  the  evidence  above  cited,  from 
the  peripheral  portion,  may  aid  in  determining  its  length,  namely,  the 
leaching  and  erosion  of  the  Peoriau  stage.  As  yet  the  fauna  and  flora 
buried  beneath  the  peripheral  portion  of  the  Wisconsin  drift  have  received 
little  or  no  attention.  Possibly  by  the  aid  of  this  line  of  study  the  ques- 
tion of  correlation  may  be  settled. 


CHAPTER   IX. 
THE  EARLY  WISCONSIN  DRIFT  SHEETS. 

GENERAL  STATEMENT. 

The  northeastern  fourth  of  Illinois  and  adjacent  portions  of  Indiana  are 
covered  by  a  sheet  of  drift  somewhat  fresher  than  the  lowan,  which  has  its 
terminus  in  the  Shelbyville  moraine,  but  which  embraces  several  morainic 
systems  of  considerable  prominence  that  lie  between  the  Shelbyville  moraine 
and  the  border  of  Lake  Michigan.  The  term  "early  Wisconsin"  is  restricted 
to  the  moraines  which  lie  outside  the  bulky  moraine  that  encircles  the  head 
of  the  lake  and  which  was  discussed  by  Chamberlin  in  the  Third  Annual 
Report  as  the  terminal  moraine  of  the  second  Grlacial  epoch.  In  that  report 
Chamberlin  referred  briefly  to  the  occurrence  of  morainic  lines  outside  the 
moraine  which  formed  the  theme  of  his  paper,,  and  recognized  the  general 
freshness  of  the  drift  and  unsculptured  contour  of  its  surface  compared 
with  that  of  the  districts  nearer  the  glacial  boundary  and  outside  the  limits 
of  the  Wisconsin  drift.-^  The  group  here  recognized  as  the  early  Wisconsin 
forms  a  somewhat  concentric  series,  as  may  be  seen  by  reference  to  the 
glacial  map  (PL  VI).  The  moraines  included  in  the  late  Wisconsin  are  not 
concentric  with  the  earlier  group.  On  the  contrary,  they  cross  the  earlier 
moraines  in  western  Indiana  and  overi-ide  the  greater  portion  of  the  district 
which  the  early  Wisconsin  occupies.  In  Illinois  the  early  Wisconsin  is  well 
exposed  outside  the  late  Wisconsin  series,  probably  better  than  in  any 
other  part  of  the  glaciated  district.  If  our  interpretations  are  correct,  it  is 
only  represented  by  a  single  moraine  in  eastern  Indiana  and  southwestern 
Ohio,  while  farther  east  it  is  entirely  concealed  by  the  later  deposits  or  so 
merged  with  them  as  to  have  escaped  recognition. 

'Third  Ann.  Kept.  U.  S.  Geol.  Survey  (for  1881-82),  1883,  p.  S31. 

191 


192  THE  ILLINOIS  GLACIAL  LOBE. 

SBCTIOK  I.     SHEIiBYVILLE  MORAINIC   SYSTEM. 

EXTENT    OF    THE    SHELBYVILLE    SHEET. 

The  outer  border  of  the  Shelbyville  sheet  is  found  in  the  Shelbyville 
moraine,  an  outline  of  whose  position  is  given  below.  This  moraine  is  but 
the  thickened  edge  of  a  drift  sheet,  which  not  only  covers  the  territory 
occupied  by  the  moraine  and  the  plain  between  it  and  the  next  succeeding 
morainic  belt,  but  apparently  extends  many  miles  to  the  north  beneath  the 
later  moraines,  for  the  fresh  di'ift  which  characterizes  this  moraine  is  found 
to  extend  below  the  base  of  the  later  moraines.  As  shown  by  Chamberlin 
in  his  discussion  of  the  di'ift  of  North  America  in  the  last  edition  of  Greikie's 
Great  Ice  Age,  there  is  an  imbricate  arrangement  of  drift  sheets  by  which 
the  later  to  some  extent  overlap  the  earlier.  This  is  found  to  be  true  of 
the  several  di%'isions  of  the  Wisconsin  sheet  as  well  as  of  the  main  divi- 
sions of  the  drift,  known  as  the  Wisconsin,  lowan,  Illinoian,  etc.,  though 
the  extent  of  overlapping  is  much  less  than  in  the  main  sheets.  As  already 
remarked,  the  several  moraines  appear  to  have  been  formed  by  readvances 
of  the  ice  of  more  or  less  consequence  rather  than  by  simple  halts  during 
its  recession. 

SHELBYVILLE  MORAINE. 

The  oldest  moraine  of  the  Wisconsin  drift,  so  far  as  recognized,  is  one 
exposed  to  view  in  central  and  eastern  Illinois  and  western  Indiana,  but 
which  is  overridden  bv  later  moraines  in  districts  farther  north  and  east. 
This  has  for  some  3rears  been  known  as  the  Shelbyville  moraine,  the  name 
being  derived  from  a  city  in  central  Illinois  which  is  situated  on  the  extreme 
southwest  point  of  the  morainic  loop.  If  we  may  judge  from  the  amount  of 
erosion  and  weathering,  it  is  somewhat  older  than  the  Altamont  moraine  of 
the  "  Minnesota  Valley  glacier"  ^  as  well  as  the  outer  Wisconsin  moraine  in 
the  eastern  United  States. 

The  thickened  edge  of  this  drift  sheet  has  usually  a  breadth  of  several 
miles,  and  merges  gradually  into  the  plain  on  the  inner  border,  so  that  it 
becomes  difficult  to  limit  the  extent  of  the  moraine.  The  crest  usually  is 
found  within  1  or  2  miles  of  the  outer  border,  and  is,  as  a  rule,  much  nearer 
the  outer  than  the  inner  border  of  the  thickened  portion  of  the  drift  sheet. 


I  See  Third  Ann.  Kept.  U.  S.  Geo!.  Survey,  p.  388. 


THE  SHELBYVILLB  MORAINE.  193 


DISTRIBUTION. 


From  Shelbyville  the  moraine  bears  eastward  to  the  Indiana  hue,  and 
deviates  but  slightly  from  a  straight  course.  There  is  a  slight  lobation  at 
the  Embarras  Valley  which  carries  the  moraine  perhaps  5  miles  south  of  a 
direct  line.  There  is  also  a  slight  reentrant  angle  south  of  Paris,  Illinois, 
carrying  it  2  or  3  miles  north  of  a  direct  line.  The  following  villages  are 
situated  near  the  south  border  of  the  moraine:  Shelbyville,  Windsor,  Para- 
dise, Trilla,  Janesville,  Diona,  Westfield,  Swango,  and  Nevins.  The  cities 
of  Mattoon,  Charleston,  and  Paris  are  situated  near  the  inner  border  of  the 
moraine. 

The  moraine  enters  Indiana  immediately  west  of  the  city  of  Terre 
Haute  and  bears  northward  along  the  west  side  of  the  Wabash  Valley  to 
northern  Vigo  County,  where  it  crosses  to  the  east  side  of  the  river,  but  con- 
tinues northward  into  Parke  County  along  the  narrow  uplands  between  the 
Wabash  River  and  Big  Raccoon  Creek  as  far  as  the  mouth  of  the  creek  near 
Montezuma.  Here  it  turns  abruptly  to  the  east  and  maintains  an  eastward 
course  across  Parke  County  and  nearly  to  Bainbridge  in  Putnam  Count}^, 
where  it  turns  southward  for  a  few  miles,  crossing  Walnut  Creek  near  the 
city  of  Greencastle.  From  Greencastle  the  course  is  eastward  past  Mount 
Meridian,  Little  Point,  and  Monrovia  to  the  vicinity  of  Mooresville,  in  north- 
ern Morgan  County.  From  Mooresville  the  course  is  southward  through 
eastern  Morgan  County,  but  the  moraine  is  so  feebly  developed  that  the  posi- 
tion is  difficult  to  outline.  The  Shelbyville  drift  sheet  apparently  extends 
into  southeastern  Morgan  and  southwestern  Johnson  counties,  its  limits  in 
these  counties  being  a  few  miles  outside  a  later  moraine.  But  in  southern 
Johnson  County  the  later  moraine  extends  to  the  extreme  limits  of  the 
Shelbyville  sheet.  A  moraine  thought  to  be  the  Shelbyville  reappears  a  few 
miles  southeast  of  Columbus,  Indiana,  and  has  been  traced  from  that  point 
eastward  into  southern  Ohio.  But  that  portion  of  the  moraine  lies  outside 
the  limits  of  the  district  covered  by  the  present  report. 

From  Shelbyville,  Illinois,  the  moraine  is  found  to  take  a  northward, 
course,  passing  a  few  miles  west  of  the  cities  of  Decatur  and  Clinton,  the 
villages  of  Macon,  Harristown,  Warrensburg,  Hallsville,  and  Waynesville 
being  situated  on  it.     From  Waynesville  the  course  is  northwestward  past 
Atlanta  to   Delavan.      The  moraine    here  takes  a  northward  course  and 

MON  XXXVIII 13 


194  THE  ILLINOIS  GLACIAL  LOBE. 

crosses  the  Illinois  River  immediately  above  tlie  citv  of  Peoria.  In  Peoria 
County  it  passes  immediately  west  of  Alta,  Dunlap,  and  Edelstein,  leaving 
the  county  near  the  corners  of  Stark  and  Marshall  counties.  It  thei'e 
becomes  merged  with  a  later  moraine  (the  Bloomington),  and  is  apparently 
covered  by  the  later  sheet  of  .drift  throughout  northern  Illinois. 

RELIEF. 

Throughout  much  of  its  course  in  Illinois  this  moraine  presents  a  bold 
relief  \\'lien  viewed  from  the  outer-border  district.  It  is  seldom  less  than 
60  feet,  and  in  places  reaches  fully  150  feet,  above  the  outer-border  plain. 
It  ordinarily  presents  a  relief  of  75  to  100  feet.  The  greatest  relief  (150 
feet)  is  found  in  Edgar  County,  between  Paris  and  Kansas.  In  Indiana 
tlie  relief  is  much  less  than  in  the  Illinois  portion  of  the  moraine.  Along 
the  Wabash  Valley  it  amounts  to  scarcely  50  feet,  while  east  from  the 
Wabash  it  is  iisually  but  20  to  40  feet. 

When  viewed  frouT  the  inner  border  the  moraine  presents  a  perceptible 
relief  only  along  a  small  portion  of  its  course.  It  usually  merges  into  the 
inner-li(irder  plain  so  gradually  that  the  border  can  scarcely  be  mapped. 
The  relief  on  the  inner-border  plain  is  more  pronounced  for  a  few  miles 
north  and  south  of  the  Illinois  River  than  elsewhere  in  its  course,  but  even 
there  it  scarcely  exceeds  75  feet. 

EANGE   IN   ALTITUDE. 

Occuin'ing  as  it  does  a  comparatively  smooth  country,  the  moraine 
presents  but  a  small  range  in  altitude.  In  the  Indiana  portion  the  highest 
points  crossed  by  it  are  near  Bainbridge,  and  have  an  elevation  of  about 
950  feet  above  tide.  At  White  River  Valley  it  but  little  exceeds  600  feet, 
and  at  the  Wabash  Valley  it  falls  slightly  below  600  feet.  At  the  Illinois- 
Indiana  line  tlie  highest  points  on  the  moraine  are  scarcely  675  feet,  but  at 
the  Kansas  geodetic  station,  only  about  20  miles  west  from  the  State  line, 
a  point  on  the  moraine  has  a  measured  altitude  of  839  feet  alcove  tide. 
.Westward  from  this  geodetic  station  the  altitude  soon  declines  to  775  feet, 
and  throughout  much  of  the  interval  between  Kansas  and  Shelb}'ville  it 
stands  750  to  775  feet  above  tide.  At  the  blutfs  of  the  Embarras  River, 
however,  it  scarce) V  exceeds  700  feet,  and  at  the  Kaskaskia  bluffs  in  Sliel- 
bvville  it  is  but  675  to  700  feet.  Throughout  much  of  the  distance  from 
SliclbAville  to  the  Sangamon  River  near  Decatur  the  altitude  is  little  more 


THE  SHELBYVILLE  MORAINE.  195 

than  700  feet,  while  at  the  river  bluff  it  is  about  650  feet.  Between  the 
Sangamon  River  and  Peoria  the  highest  points  along  the  crest  are  about 
800  feet,  and  the  crest  seldom  falls  below  700  feet.  Near  the  east  bluif  of 
the  Illinois,  at  Grrovelaud,  the  altitude  is  785  feet,  or  more  than  350  feet 
above  the  Illinois  River;  but  in  the  northeast  part  of  Peoria  the  moraine 
appears  on  the  west  bluff  of  the  river  at  an  altitude  scarcely  200  feet  above 
the  stream.  Passing  northward  the  moraine  soon  rises  to  a  height  of  800 
feet  and  stands  near  this  elevation  throughout  its  course  in  northern  Peoria 
Coimty  and  in  eastern  Stark  County  to  where  it  is  overridden  by  the 
Bloomington  moraine. 


SURFACE    CONTOURS. 


Although  this  moraine  constitutes  the  margin  of  a  thick  sheet  of  drift 
and  has  usually  considerable  relief  on  its  outer  border,  it  pi-esents  in  general 
a  comparatively  smooth  surface,  sharp  knobs  being  developed  only  at  a  few 
points,  and  sAvells  or  undulations  of  the  surface  being  of  a  gentle,  unobtru- 
sive type.  In  places  it  has  no  more  undulation  than  has  the  plain  north  of 
it.  Were  one  not  aware  of  the  great  relief  above  the  outer-border  district 
and  certain  that  this  relief  is  due  entirel}^  to  the  presence  here  of  a  sheet 
of  drift  not  found  in  the  outer-border  district,  one  might  well  question  the 
propriety  of  considering  this  a  moraiuic  belt.  But  tliese  criteria  place 
beyond  question  the  termination  of  the  ice  invasion  along  this  line,  and  no 
better  term  than  moraine  seems  applicable  to  such  a  thickened  drift  ter- 
minus. In  this  connection  it  may  be  remarked  that  where  there  is  an 
attenuated  drift  border  at  the  margin  of  the  glaciated  district,  the  term 
glacial  boundary  seems  preferable  to  moraine,  but  in  the  case  of  the  margin 
of  a  later  drift  sheet  which  lies  back  some  distance  from  the  glacial  bound- 
ary it  would  seem  necessary  to  substitute  some  definition  or  explanatory 
term.  In  case  the  later  drift  sheet  under  discussion  should  have  an  attenu- 
ated border  the  tenn  moraine  scarcely  seems  applicable,  and  it  would  be 
preferable  to  substitute  the  term  Wisconsin  boundary,  but  if  the  drift  sheets 
have  a  thick  edge  and  bold  relief,  as  is  generally  the  case,  the  term  moraine 
seems  applicable  even  though  no  sharp  morainic  contours  are  present.  As 
it  is,  however,  a  portion  of  the  margin  of  this  drift  sheet  ]5resents  charac- 
teristic morainic  features,  and  these  features  pass,  by  insensible  gradations, 
into  the  more  nearl}-  plane  portions  of  the  border.  To  set  forth  fuUv  the 
topography  of  this  border  a  somewhat  detailed  description  is  necessary. 


196  THE  ILLINOIS  GLACIAL  LOBE. 

At  very  few  points  between  Shelbyville  and  Peoria  are  there  knolls  or 
ridges  worthy  of  note,  almost  the  entire  surface,  both  along  the  crest  and 
the  outer  face  of  the  moraine  as  well  as  its  inner  slope,  being  nearly  plane. 
The  outer  face  occupies  a  Avidth  of  a  mile  or  more.  It  shows  slight 
irregularities  of  outline  in  the  form  of  projecting  points  and  bay-like  reces- 
sions, which  cause  a  deviation  of  a  half  mile  to  a  mile  or  more  from  a  direct  line. 
North  from  the  Sangamon  River  the  surface  is  somewhat  more  undulatory 
than  in  the  interval  between  the  Kaskaskia  and  Sang-amon  rivers,  but  the 
drift  swells  are  usually  but  10  to  20  feet  in  height.  The  sharpest  drift  knoll 
noted  is  about  2  miles  north  of  Decatur  and  is  scarcely  50  feet  in  height. 
Knolls  and  ridges  west  of  Forsythe  are  30  feet  or  more  in  height.  In  south- 
western McLean  and  southeastern  Tazewell  counties  there  are  several 
sharply  outlined  small  ridges  lying  back  6  or  G  miles  from  the  outer  border 
of  the  drift  sheet  and  trending  parallel  with  it.  They  rise  20  or  30  feet, 
and  in  places  50  feet  or  more,  above  the  bordering  jjlains.  In  the  portion 
of  the  plain  between  the  Mackinaw  and  Illinois  rivers  there  is,  in  addition 
to  the  relief  of  50  or  60  feet  on  the  inner  Ijorder,  an  undulatory  surface 
with  SAvells  10  to  25  feet  in  height.  The  portion  north  from  Peoria  has 
only  gentle  swells  10  to  15  feet  in  height,  but  with  these  swells  there  are 
occasional  basins  3  to  6  feet  in  depth,  which  add  somewhat  to  the  expression 
of  the  moraine.  The  moraine  here  is  narrowed  to  a  belt  only  2  miles  or  so 
in  width,  and,  as  the  relief  is  50  or  60  feet,  the  expression  is  more  pro- 
nounced than  throughout  the  greater  part  of  the  border  of  this  drift  sheet. 

Eastward  from  Shelbyville  the  moraine  is  found  to  have  ver}'  little 
expression  in  eastern  Shelby  County,  the  surface  being  nearly  as  smooth 
as  that  of  the  plain  on  the  north.  Upon  approaching  the  Embarras  Valley 
in  Coles  County,  the  moraine  is  found  JEO  be  separable  into  at  least  three 
distinct  ridges  with  east-west  trend.  The  ridges  each  have  a  nearly  plane 
surface,  with  smooth  slopes,  but  present  a  relief  of  30  to  50  feet  above  the 
intervening  sags.  On  the  east  side  of  the  Embarras  River,  near  the  line  of 
Coles  and  Cumberland  counties,  a  few  knolls,  10  to  25  feet  in  height, 
appear  on  the  outer  face  of  the  outer  ridge.  In  Edgar  County  the  moraine 
consist  of  two  more  or  less  distinct  ridges.  They  are  more  distinct  in  the 
southwestern  than  in  the  southeastern  part  of  the  county.  In  the  vicinity 
of  Grand  View  and  westward  into  Coles  Count}'  the  ridges  stand  about 
50  feet  above  the  sag  which  separates-  them.     The  south  ridge  is  forest 


THE  SHELBYVILLE  MOEAINE.  197 

covered,  while  the  north  ridge  was  a  prairie  at  the  settlement  of  the 
county.  Each  ridge  is  characterized  by  low  knolls  and  shallow  basins. 
Occasionally  the  knolls  reach  a  height  of  30  feet,  but  they  are  usually  only 
10  or  15  feet  in  height.  In  the  vicinity  of  NeAdns  a  narrow  outer  ridge 
appears  for  a  few  miles,  which  has  sharp  knolls  30  feet  or  more  in  height. 

Upon  passing  into  Indiana  the  moraine  loses  the  definite  ridging  which 
it  displays  in  Coles  and  Edgar  counties,  Illinois,  and  is  represented  in 
northwestern  Vigo  County  by  a  sheet  of  drift  carrying  only  occasional 
knolls.  In  a  few  cases  the  knolls  reach  a  heig'ht  of  nearly  50  feet.  The 
portion  of  the  moraine  lying  between  the  Wabash  River  and  Big  Raccoon 
Creek  is  gently  nndulatory  and  more  definitely  ridged  than  that  in  north- 
western Vigo  County.  Froni  the  Wabash  Valley  eastward  to  Greencastle 
the  moraine  has  generally  a  gently  undulating  surface,  with  few  knolls 
exceeding  20  feet  in  height.  From  Grreencastle  eastward  the  drift  sheet 
seems  to  be  represented  in  places  only  by  small  knolls  and  ridges,  standing 
but  15  to  25  feet  above  the  outer  border.  Among  these  knolls  and  ridges 
are  plains  of  considerable  extent  in  Avhich  the  Shelbyville  sheet  seems  to 
be  very  attenuated.  It  becomes  difficult  to  trace  the  border  by  the  topog- 
raphy, and  it  has  been  found  necessary  to  rely  mainly  upon  the  structure 
of  the  drift  deposits.  As  indicated  below,  the  removal  of  the  loess  and 
the  replacement  by  a  bowldery  drift  gives  the  line  at  which  this  invasion 
terminated  sufficient  definiteness  to  admit  of  mapping. 

STKUCTURE    AND    THICKNESS    OF    THE    DRIFT. 

With  the  exception  of  the  surface  portion,  which  is  variable  in  structure 
because  of  local  deposits  of  silt,  sand,  or  gravel,  the  drift  in  this  moraine 
is,  in  the  main,  a  typical  till.  For  a  depth  of  8  to  12  feet,  and  occasionally 
for  20  or  25  feet,  from  the  surtace  it  presents  a  brownish-yellow  color, 
which  changes  below  to  a  grayish  yellow  and  yellowish  gray  and  finally  to 
a  blue  gray.  The  blue-gray  till  constitutes  the  main  body  of  the  drift 
sheet.  It  as  about  as  thick  as  the  measure  of  the  relief  of  the  drift  sheet 
above  the  outer-border  plain,  which  in  Illinois,  as  above  noted,  ranges 
from  60  to  about  150  feet,  and  in  Indiana  seldom  exceeds  40  feet.  In 
places  a  bed  of  sand  or  gravel  is  found  at  the  junction  of  the  yellow  and 
blue  tills,  suggesting  that  they  may  represent  distinct  deposits,  but  there 
are  many  more  places  exposed  to  view  where  the  yellow  till  grades  down- 
ward into  the  blue  till.     Furthermore,  tliere  are  included  within  both  the 


198  THE  ILLINOIS  GLACIAL  LOBE. 

yellow  and  the  blue  till  local  beds  of  sand  or  gravel  similar  to  those  at 
their  junction.  It  seems  on  the  whole  probable  that  the  two  clays  consti- 
tute but  a  single  deposit,  and  that  the  color  distinction  has  been  largely 
acquired  since  deposition.  This  view  seems  supported  by  the  fact  that  the 
deposits  are  similar  in  structure,  even  in  the  number  of  striated  stones  and 
in  the  calcareous  rock  flour  which  they  contain.  The  surface  portion  of 
the  yellow  clay  to  a  depth  of  4  to  6  feet  is  more  highly  oxidized  and  shows 
greater  discoloration  than  the  lower  portion,  and  contains  but  little  cal- 
careous material,  but  these  features  seem  to  be  due  in  the  main  to  weather- 
ing subsequent  to  deposition  and  not  to  original  differences. 

Surface  bowldei's  are  irregularly  distributed  over  the  moraine.  They 
are  nowhere  rare,  and  occasionally  become  so  numerous  as  to  be  trouble- 
some in  cultivating  the  land.  In  eastern  Illinois  they  are  most  conspicuous 
in  the  southwestern  part  of  Edgar  County.  The  bowlders  consist  almost 
entirely  of  Canadian  rocks,  and  few  of  them  exhibit  striae  or  glacial  planing. 
Some  are  sharply  angular,  a  feature  which  indicates  that  but  slight  surface 
change  has  been  produced  since  they  were  deposited.  This  being  the  case 
the  absence  of  striae  is  due  not  so  much  to  weathering  and  removal  after 
striation  had  occurred  as  to  an  escape  from  striating  agencies.  It  is  thought 
that  their  transportation  may  have  been  at  a  level  considerably  above  the 
base  of  the  ice  sheet.^ 

The  portion  of  the  Shelbyville  moraine  north  of  Shelbyville  carries  a 
larger  amount  of  surface  silt  than  the  portion  east  of  that  city.  Not  only 
the  moraine  but  the  district  to  the  east,  for  a  distance  of  perhaps  20' miles, 
has  a  coating  of  silt  so  thick  that  bowlders  are  completely  concealed,  for  it 
not  infrequently  reaches  a  depth  of  5  or  6  feet.  On  the  portion  east  from 
Shelbyville  the  silt  is  usually  but  1  to  2  feet  in  depth,  so  that  bowlders  are 
frequently  seen  at  the  surface.  In  the  vicinit}'  of  the  Wabash  ^^alley,  how- 
ever, the  thickness  is  4  to  6  feet.  The  silt  is  usually  of  a  brownish-yellow 
color,  much  like  that  of  the  oxidized  till  underneath  it,  though  slightly  paler 
than  the  till.  Where  thickest  it  is  somewhat  calcareous  in  the  lower  portion 
and  carries  small  molluscan  shells  of  land  and  water  species,  similar  to 
those  foun<l  in  the  lowan  loess.  The  silt,  however,  is  usually  leached  to  a 
depth  of  3  or  4  feet.     This  silt  appears  to  have  been  deposited  very  soon 

'  Comp.  Cliiuulierliti,  .lour.  Geol.,  Vol.  I,  pp.  47-fiO. 


THE  SHELBYVILLB  MORAINE.  199 

after  the  till  whicli  underlies  it,  for  the  latter  is  not  leached  except  where 
the  sm'face  leacliiug  has  extended  below  the  base  of  the  silt.  As  to  the 
origin  of  this  silt,  it  may  be  remarked  that  the  ealcareousness  seems  to  indi- 
cate derivation  from  the  Shelbyville  drift  rather  than  from  the  lowan  loess. 
The  loess  of  the  outlying  districts  is  so  thoroughly  leached  to  a  depth  of 
several  feet  that  it  can  liardly  he  the  source  of  supply.  Exposures  were 
found  near  Princeville,  in  the  district  west  of  the  Shelbyville  moraine, 
where  a  fresh  calcareous  silt  such  as  caps  the  moraine  overlies  the  lowau 
loess.  Acid  tests  also  indicate  that  the  surface  silt  is  more  calcareous  than 
the  underlving  loess. 

Beneath  this  drift  sheet,  at  about  the  level  of  the  district  outside  the 
moraine,  the  earlier  or  Illinoian  drift  is  struck.  The  junction  between  the 
earlier  and  later  drift  is  often  marked  by  a  soil  or  other  equally  clear  indi- 
cation of  an  old  land  surface.  The  passage  from  one  drift  to  the  other  is 
readily  recognized  by  well  di-illers  because  of  the  difference  in  hardness, 
the  earlier  di-ift  being-  partially  cemented  and  much  inore  difficult  to  pene- 
trate than  the  overlying  later  drift  sheet.  As  noted  below,  exposures  of 
the  earlier  di-ift  ^vere  found  in  the  Illinois,  Kaskaskia,  and  Embarras  valleys 
in  Illinois.  The  majority  of  the  streams  in  Illinois  fail  to  reach  the  level 
of  the  earlier  drift  in  their  passage  through  the  moraine.  Those  of  Indiana 
more  often  have  cut  into  the  older  di-ift. 

The  thickness  of  the  Shelbyville  drift  in  the  Illinois  portion  of  the 
moraine  is  much  greater  than  that  of  the  underlying  older  di-ift,  the  aver- 
age thickness  of  the  former  being  nearlv,  if  not  quite,  100  feet,  while  the 
latter  attains  that  thickness  only  in  the  valleys  or  lowland  tracts  which  it 
filled,  and  has  in  this  region  a  general  thickness  scarcely  half  as  great  as 
that  of  the  Shelbyville  drift  sheet.  Our  knowledge  of  the  thickness  of  the 
Shelbyville  sheet  is  based  mainly  upon  the  relief  of  the  moraine,  and  the 
estimate  of  the  thickness  of  the  older  di-ift  is  based  upon  its  thickness  in 
districts  outside  the  moraine,  rather  than  upon  borings  within  the  limits  of 
the  moraine,  there  being  few  wells  which  have  reached  its  bottom.  There 
are,  however,  a  sufficient  number  of  records  of  deep  wells  along  the 
moraine,  or  in  the  districts  north  of  it,  to  furnish  a  fair  knowledge  of  this 
earlier  drift  sheet. 

As  may  be  inferred  from  previous  statements,  the  Shelbyville  drift 
sheet  is  much  thinner  in  the  Indiana  than  in  the  Illinois  portion  of  the 


200  THE  ILLINOIS  GLACIAL  LOBE. 

moraiue.  Several  of  the  valleys  have  been  cut  tln-(ni<ili  it  to  tlie  iinder- 
lyiug  older  diift,  and  ra%'ines  heading  in  the  newer  drift  ver\-  frequentlv 
reach  a  level  below  its  base  before  emerging-  into  the  older  drift  disti-ict. 
Wells  also  not  infrequently  pass  into  the  older  ch-ift  before  obtaining  a 
supply  of  water.  It  is  estimated  that  the  thickness  of  the  Shelbvville 
di-ift  sheet  along  the  coui'se  of  the  moraine  in  western  Indiana  averaaes 
only  25  or  30  feet  and  rarely  exceeds  40  feet.  On  the  plain  north  of  the 
moraine  it  apparently  falls  below  20  feet.  Before  the  deposition  of  this 
sheet  shallow  interglacial  valleys  appear  to  have  been  opened  and  where 
the}'  were  filled  the  thickness  of  the  Shelbyville  drift  is  in  some  places 
perceptiblv  greater  than  on  the  neighboring  uplands,  so  that  valleys  40 
feet  or  more  in  depth  have  in  some  cases  failed  to  cut  down  to  its  bottom. 
The  older  di-ift  in  western  Indiana  fills  the  preglacial  valleys  to  consider- 
able depth,  often  exceeding  100  feet.  But  on  uplands  its  thickness  is  much 
less  and  apparently  averages  but  little  greater  than  the  Shelbvville  sheet. 

In  the  latter  part  of  this  rejjort,  and  in  Water-Supjily  and  Irrigation 
Paper  No.  26,  on  Wells  of  Southern  Indiana,  numerous  sections  will  be 
found  which  set  forth  the  structure  of  the  drift  along  the  line  of  this 
moraine.  It  is  necessary,  therefore,  to  call  attention  to  l)ut  a  few  of  the 
more  important  sections  in  this  place.  These  are  presented  in  order  from 
the  east  w^estward. 

A  well  showing  a  large  amount  of  drift  was  sunk  by  L.  B.  liumplnies 
in  the  west  part  of  the  village  of  Rockville.  For  about  40  feet  the  till  was 
found  to  be  of  fresh  color  and  easy  to  penetrate.  This  probably  marks  the 
depth  of  the  Shelbyville  di'ift  sheet,  for  a  hard  till  was  then  entered,  wdiich 
continued  to  a  depth  of  168  feet.  Some  wells  in  the  village  of  Rock^^lle 
have  passed  thr(mgli  a  black  soil  at  the  base  of  the  Shelbyville  sheet.  In 
some  cases  wdiere  the  ground  is  slightly  lower  than  at  the  well  just  noted, 
it  is  found  at  a  depth  of  but  17  to  20  feet.  With  the  soil  there  is  usually 
consideral)le  wood.  In  western  Parke  County,  in  the  portion  oi  the  moraine 
between  Big  Raccoon  Creek  and  the  Wabash  River,  wells  at  several  farm 
houses  have  passed  through  a  black  soil  at  the  base  of  the  Shelbyville  ilrift 
sheet.  On  a  tril1utar^-  of  Big  Raccoon  Creek,  on  tlie  farm  of  E.  D.  Wicks, 
in  sec.  H,  T.  14,  R.  8  W.,  nn  exposure  of  soil  below  till  is  found  at  a  lower 
elevation  tlian  that  struck  in  tlie  neighboring  wells,  there  being  fully  50  feet 
of  till  ;il)ove  the  soil,  while  in  the  wells  there  is  usuallv  but  20  or  26  feet. 


THE  SHELBYVILLB  MORAINE.  201 

It  is  probable  that  the  lower  elevation  of  the  soil  is  due  to  its  being  formed 
in  an  interglacial  valley,  thoug-h  possibly  it  marks  a  lower  horizon  than  the 
base  of  the  Shelbyville  sheet.  The  soil  contains  much  wood  and  mats  of 
decayed  leaves.  A  spring  issues  from  this  soil  bed  which  carries  a  small 
amount  of  inflammable  gas. 

An  artesian  well  drilled  by  the  Roman  Catholic  Sisters  of  Providence 
at  St.  Mary's  penetrates  100  feet  of  drift,  of  which  the  upper  75  feet  is  till 
and  the  remainder  clay  and  quicksand.  The  full  section  of  the  well  to  a 
depth  of  1,955  feet  is  published  in  the  Twenty-first  Annual  Report  of  the 
Indiana  Geological  Survey  (p.  524). 

At  Sanford,  on  the  State  line  of  Indiana  and  Illinois,  the  drift  is  found 
to  have  a  thickness  of  147  feet.  It  is  thought  that  onl}^  the  upper  25  feet 
belongs  in  the  Shelbyville  drift  sheet.  The  following  record,  except  the 
parenthetical  portions,  which  are  added  by  the  writer,  appears  in  the  Indiana 
Greological  Report  for  1875  (p.  94): 

Section  of  drift  in  a  well  at  Sanford,  Illinois. 

Ft.  in. 

Surface  (yellow  till) 15  o 

Saud - . , 6  0 

Sand  and  cl.ay 4  o 

Hardpan  (Illinoian?) 66  0 

Brown  clay _  _ lo  3 

Bine  clay ' g  4 

Sand 0  4 

Blue  clay 37  q 

'J"otal 147    5 

At  Paris  the  waterworks  well  was  sunk  to  a  depth  of  60  feet,  of  which 
the  upper  50  feet  is  till  and  the  remainder  sand  and  gravel.  At  the  base  of 
the  till  considerable  wood  is  found.  It  seems  probable  that  the  well  extends 
to  the  base  of  the  Shelbyville  drift  sheet. 

At  Charleston  the  distance  to  rock  ranges  from  30  feet  or  less  to  at 
least  127  feet,  a  well  in  the  north  part  of  the  city  having  reached  no  rock 
at  that  depth.  Along  the  Embarras  Valley,  south  of  Charleston,  several 
exposures  were  found  in  which  the  Illinoian  drift,  with  the  capping  of  white 
clay,  appears  below  the  till  of  the  Shelbyville  sheet.  The  northernmost 
exposure  noted  is  a  few  rods  Avest  of  the  iron  bridge,  3  miles  southeast  of 
Charleston.  At  that  point  the  Shelbyville  drift  sheet  extends  to  within 
about  20  feet  of  the  river  level.  Near  the  south  line  of  Coles  County  the 
older  (Illinoian)  drift  is  found  to  reach  an  elevation  50  or  60  feet  above  the 


202  THE  ILLINOIS  GLACIAL  LOBE. 

river  bed.  Exposures  of  the  older  drift  with  the  capping-  of  white  clay  Avere 
also  noted  In  northern  Cumberland  County,  along  western  tributaries  of 
the  Embarras  River. 

Records  of  several  wells  in  the  vicinity  of  Lerna  were  obtained  in 
which  no  rock  was  entered  at  a  depth  of  100  feet,  and  one  boring  reached 
a  depth  of  132  feet  without  striking  rock.  A  large  part  of  the  drift  appears 
to  belong  to  the  Shelbyville  sheet. 

At  Mattoon  a  coal  shaft  lias  the  following  section,  as  reported  in  the 
Geology  of  Illinois,  which  suggests  that  the  Shelbyville  sheet  there  may 
be  but  a  few  feet  in  depth  : 

Section  of  drift  in  a  coal  shaft  at  Mattoon,  Illinois. 

Feet. 

Surface  soil 5 

Yellow  clay 8 

Sand  (l)lue) 3 

Harclpan  (Illinoiauf ) 35 

Sand  and  gravel 17 

Blue  clay  and  gravel 38 

Total  drift 106 

At  Windsor  the  town  well  has  a  depth  of  127  feet  and  does  not  reach 
rock.  It  is  reported  that  a  soft  blue  till  sets  in  within  10  feet  of  the  surface, 
and  extends  to  a  depth  of  90  feet.  Here  a  hard,  stony,  brown  clay,  prob- 
ably Illinoian,  was  entered,  which  changed  within  a  few  feet  to  sandy 
water-bearing  clay,  and  the  amount  of  water  gradually  increased  until  a 
good  supply  was  obtained  at  a  depth  of  127  feet.  Several  prospect  borings 
for  water  have  been  made  in  Windsor  hj  Jerry  Linnville,  in  one  of  which  a 
black  muck  was  found  at  about  100  feet.  This  was  probably  at  the  base 
of  the  Shelbyville  drift  sheet,  and  at  the  same  horizon  as  the  brown  clay 
struck  at  90  feet  in  the  town  well.  A  slight  amount  of  gas  was  found  near 
the  level  of  tlii.s  muck.  It  appears  to  have  been  at  a  level  slightly  lower  than 
the  muck,  and  lience  is  less  likely  to  have  been  derived  from  It  than  if 
found  at  !i,  higlier  level.  Possibly  its  source  is  from  underlying  shale.  It  is 
thought  that  one  boring-  reached  the  shale  at  170  feet. 

Along  the  Kaskaskia  Valley  in  the  vicinity  of  Shelbyville  there  are 
exposures  of  the  Illinoian  drift,  capped  by  a  white  clay  similar  to  the 
surface  white  c-la}-  of  tlu^  outer-border  district,  but  hei-e  overlain  by  about 
20  feet  of  till  of  tlic  Sh('ll)yville  sheet      One  exposure  Is  found  within  the 


THE  SHELBYVILLE  MORAINE.  203 

citv  of  Shelby  ville,  in  the  street  g-rading  leading  from  the  court-house  east- 
ward to  the  wagon  bridge.  Another  is  found  about  a  half  mile  east  of  the 
wagon  bridge,  where  a  road  leads  off  to  the  south.  At  this  place  there  is 
a  well-defined  soil  (Sangamon)  between  the  white  clay  and  the  underlying 
Illinoian  drift.  The  contrast  in  hardness  of  the  drift  sheets  is  very  striking, 
the  drift  of  the  ShelbyA'ille  sheet  being  fresh  and  easily  penetrated  by  spade 
or  trowel,  while  the  older  drift  is  partially  cemented  and  its  brownish-blue 
till  is  traversed  by  veins  of  deep-brown  color  not  seen  in  the  blue  till  of  the 
Shelbyville  sheet.  No  better  place  to  study  the  two  drift  sheets  has  been 
found  than  is  afforded  in  the  vicinity  of  this  city.  There  are  exposed  in 
vertical  section  numeroiis  cuttings  and  exposures  of  both  drift  sheets, 
including  also  the  buried  soil  and  the  buried  white  clay  which  caps  the  older 
drift.  The  topographic  features  of  the  two  sheets  are  also  well  displayed. 
The  contrast  is  not  exceptionally  striking  here,  but  the  opportunity  for 
making  comparisons  is  exceptionally  good. 

In  the  vicinity  of  Macon,  the  first  town  of  importance  situated  on  the 
moraine  north  from  Shelbyville,  an  inexhaustible  supply  of  water  is  found 
in  sand  and  gravel  near  the  base. of  the  Shelbyville  diift  sheet  at  a  depth 
of  100  to  120  feet.  The  quantity  of  water  is  so  great  as  to  have  jjrevented 
the  sinking  of  a  coal  shaft  at  this  town.  Gas  in  considerable  amount  has 
been  encountered  in  wells  between  Macon  and  Decatur,  and  also  over  a 
considerable  area  east  of  Macon.  The  gas  is  found  in  beds  of  sand  and 
gravel,  which  are  in  some  instances  located  in  the  lower  part  of  the  Shelby- 
ville drift  sheet,  but  more  often  in  beds  associated  with  the  underlying 
Illinoian  drift.  In  some  cases  the  gas  is  found  in  the  shale  which  immedi- 
ately underlies  the  drift.  Well  drillers  can  readily  distinguish  the  Shelby- 
ville drift  sheet  from  the  underlying  Illinoian  drift,  and  they  report  that  it 
is  not  imcommon  to  find  a  bed  of  white  clay,  such  as  caps  the  district 
outside  the  Shelbyville  sheet,  at  a  corresponding  elevation  under  the 
Shelbyville  sheet.  The  thickness  of  the  Shelbyville  sheet  ranges  from 
60  to  120  feet  or  more,  and  there  is  usually  so  little  sand  and  gravel  asso- 
ciated with  it  that  the  tubular  wells  are  sunk  into  the  underlying  older 
drift. 

At  Decatur  the  records  of  a  coal  shaft  and  air  shafts  show  marked  con- 
trasts in  the  drift  sections.     The  distance  between  the  shafts  is  about  one- 


'  Published  in  the  Geology  of  Illinois,  Vol.  VIII,  pp.  15  and  48. 


204  THE  ILLINOIS  GLACIAL  LOBE. 

half  mile.     The  following  is  the  section  of  the  air  shaft  as  furnished  by 
Charles  Hansel,  of  Decatur: 

Section  of  drift  in  an  air  shaft  at  Decatur,  Illinois. 

Feet. 

Soil  and  loamy  clay 25 

Sand  and  water,  flow  of  400  gallons  per  minute 30 

Blue  clay 4 

1  )rLft wood  and  soil 2 

Green  sand 4 

( ■  ray  sand 6 

Hard  blue  clay 9 

Sand  and  gravel,  fine  strata 37 

Hardpan 23 

Total  drift = 140 

The  bed  of  driftwood  and  soil  was  struck  at  about  the  level  of  the  sur- 
face of  the  older  drift  sheet  outside  the  moraine;  it  may  be  either  Peoriau 
or  Sangamon.  In  the  coal  shaft  two  soils  are  reported,  of  which  the  lower 
one  appears  to  be  in  the  midst  of  the  older  drift;  at  least  it  is  placed  below 
a  gravelly  hardpan,  such  as  is  commonly  reported  when  the  older  drift  is 
struck.     The  following  is  the  section  as  published  in  the  Geology  of  Illinois : 

Section  of  drift  in  a  coal  shaft  at  Decatur,  Illinois. 

Ft.    ill. 

Soil  and  clay 31  0 

Sand  with  two  clay  bands 11  0 

Quicksand 2  6 

Tough  clay : 4  0 

Black  soil 2  6 

Sand 2  0 

Clay 1 3  0 

Greenish  sand 6  0 

Gravelly  hardpan 11  0 

Black  soil 2  0 

Quicksand 4  0 

Gravelly  clay 24  0 

Quicksaud C  6 

Total  drift 109     0 

Many  wells  iu  the  vicinity  of  Decatur  are  sunk  to  a  depth  of  about  80 
feet  l)efore  obtaining  a  strong  supply  of  water.  The  till  is  apparently  a 
nearly  unbroken  sheet.  On  the  moraine  west  of  Decatur,  in  the  vicinit}'  of 
Harristown,  wells  are  often  sunk  through  blue  till  to  a  depth  of  100  or  125 
feet.  It  is  tliought  that  they  obtain  their  supply  of  water  at  or  near  the 
base  of  the  Shelb\-ville  sheet.  North  from  Decatur,  in  the  vicinitv  of 
Maroa,  about  60  feet  of  blue  till  is  penetrated  before  water-bearing  saud  or 


THE  SHBLBYVILLE  MORAINE.  205 

gravel  Is  reached.  The  waterworks  wells  at  Maroa  have  a  depth  of  about 
1 00  feet  and  terminate  in  gravel. 

At  Clinton  the  drift  is  found  to  have  the  remarkable  thickness  of  352 
feet,  making  the  altitude  of  the  rock  surface  there  but  380  feet  above 
tide.  In  the  record  published  by  Worthen^  twenty-seven  changes  in  drift 
structure  are  reported.  The  lower  140  feet  of  the  drift  is  entirely  sand  and 
gravel,  while  in  the  remaining  212  feet  there  are  thin  beds  of  sand  and 
gravel  whose  combined  thickness  amounts  to  but  47  feet,  the  bulk  of  the 
deposit  being  of  clayey  constitution.  Another  boring  about  one-half  mile 
north  of  the  one  recorded  is  reported  to  have  penetrated  only  270  feet  of 
drift.  In  the  vicinity  of  Hallsville,  6  miles  west  of  Clinton,  several  gas 
wells  have  been  obtained  in  beds  of  gravel  below  blue  till  at  depths,  ranging 
from  96  feet  to  about  140  feet.  Some  of  these  wells  furnished  a  sufficient 
amount  of  gas  to  supply  fuel  for  one  or  more  stoves,  but  at  last  accounts 
(1897)  the  supply  was  decreasing. 

The  section^  of  one  of  these  i>-as  wells  on  James  Barnett's  farm  shows 


& 


an  interesting  series  of  drift  sheets  separated  by  buried  soils,  as  follows : 
Section  of  a  gas  u-eJl  in  drift  near  Clinton,  Illinois. 

Feet. 

1.  Soil  anil  yellow  clay , 15 

2.  Blue  clay 30 

3.  Black  soil,  with  wood 3 

4.  Drab  clay _ y 

5.  Black  mold  and  driftwood 8 

6.  Drab-colored  day 20 

7.  Driftwood  (log?) 2 

8.  Drab-colored  clay ■  21 

9.  Hardpan 12 

10.  Drab-colbred  clay _ J 

11.  Greenisb  clay _ lo 

12.  Saud,  etc 5 

Total ~^ 

In  this  section  it  is  probable  that  only  1  and  2  are  to  be  included  in 
the  Shelbyville  drift.  Number  3  apj^ears  to  be  the  Peorian  soil  Avhich  caps 
the  loess  in  the  region  outside  the  moraine,  while  4  probably  represents  the 
loess  and  5  the  Sangamon  soil  between  the  loess  and  Illinoian  drift. 

In  the  vicinity  of  Atlanta  the  drift  has  a  known  tliickness  of  over  200 
feet.     Records  of  several  wells  were  obtained  which  range  from  125  to  210 

'  Geology  of  Illinois,  Vol.  VIII,  p.  34. 
'Published  in  the  Geology  of  Illiiioi 


)  Geology  of  Illinois,  Vol.  VIII,  pp.  58,59;  al.so  p.  13. 


206  THE  ILLINOIS  GLACIAL  LOBE. 

feet  ill  depth,  and  none  of  tlieni  reached  the  rock.  They  penetrate  about 
100  feet  of  soft  till  of  hlue  color,  probably  referable  to  the  Shelby ^alle 
sheet,  beneatli  which  a  harder,  brownish -blue  till  is  entered,  which  seems 
referable  to  the  Illinoian  drift.  The  village  of  Atlanta  obtains  its  water- 
works supply  from  two  8-iiich  Avells  151  feet  in  depth.  The  following 
detailed  record  of  the  drift  beds  penetrated  was  furnished  by  J.  S.  Bevan, 
mayor  of  Atlanta: 

Section  of  a  trell  at  the  iratericorln  at  Atlanta,  Illinois. 

Feet. 

Black  soil 3 

Yellow  clay 13 

Blue  clay 10 

Gray  saiul  aud  gravel - 10 

Blue  clay - 2 

Sand  aud  gravel 9 

White  clay  and  sand 7 

Blue  clay  with  gas 3 

White  sand  aud  gravel 10 

Sand - 6 

Dry  sand  aud  gravel  with  gas 13 

Blue  clay 1 

Clay,  sand,  gravel,  aud  gas 16 

Hardpan - 9 

Black  drift  dirohably  Peorian  soil) 6 

White  clay  (probably  lowan  silt) 2 

Green  clay  (probably  lowau  silf ) i 

Hardpan  (probably  Illinoian  till) - -.  10 

Gravel  and  water 12 

Total - 151 

The  black  drift  noted  in  this  Avell  section  has  about  tlie  level  of  the 
plain  outside  the  Shelby ville  drift  sheet,  and  is  probably  a  soil  formed  above 
the  lowan  silt. 

In  the  ^'icinity  of  Dela^-an  the  drift  over  an  area  of  several  square 
miles  may  exceed  300  feet  in  depth,  for  the  Shelbyville  sheet  here 
encroaches  on  a  preglacial  valley;  the  thickness  in  one  well  is  313  feet. 
The  city  Avaterworks  well  is  'l-iO  feet  in  dei)tli  and  has  tlie  following  section, 
furnished  hx  J.  I).  Mount,  citA'  marshal: 

Section  of  the  a-cll  at  n-atcra-orhs  in  J)elaraii,  Illinois. 

I'cut. 

Yellow  bowlder  clay  (Shelliy ville  sheet) 15 

Blr.e  bowlder  day  (Sbelbyvillo  sheet) 60 

lilack  111  lick  with  wood  (probably  Peorian  soil) 6 

Solt  green  clay  (probably  lowau  silt) 8 

Hard  gray  bowlder  day  (jirobably  Illinoian  till) SO 

Gray  sand  containing  water 122 

Total 240 


THE  SHELBYVILLE  MOKAII«fE.  207 

The  black  muck  penetrated  in  this  well  is  at  the  base  of  the  Shelb}-- 
ville  drift  sheet.  Mr.  Mount  reports  that  several  wells  in  the  vicinity  of 
Delavan  have  encountered  a  similar  bed  of  muck  at  this  horizon. 

Attention  was  called  above  to  exposures  along-  the  Toledo,  Peoria  and 
Western  Railwaj  east  of  Peoria,  and  also  on  the  east  bluff  of  the  Illinois 
opposite  that  city,  where  the  Shelbyville  sheet  is  underlain  by  a  bed  of 
fossiliferous  loess  similar  in  texture  and  in  age  to  that  found  on  the  surface 
of  the  lUinoian  drift  outside  the  limits  of  the  Shelbyville  drift  sheet.  The 
loess  is  8  to  12  feet  in  thickness,  or  about  the  same  as  on  the  uplands  outside 
the  Shelbyville  sheet.  It  occurs  at  a  corresponding  elevation  of  about  200 
feet  above  the  Illinois  River.  Beneath  it  there  is  exposed  full}-  100  feet  of 
the  older  drift  sheet.  The  thickness  of  the  Shelbyville  drift  sheet  above 
this  loess  varies  greatly,  being  in  places  but  20  feet,  while  elsewhere  it  is  75 
or  100  feet.  The  variation  is  due  in  part  to  erosion  and  in  part  to  original 
inequalities  of  thickness.  As  previously  noted,  these  exposures  afford 
excellent  opportunity  for  contrasting  the  Shelbyville  sheet  with  the  older 
drift  and  for  studying  soils  formed  on  tlie  surface  of  the  older  drift. 

In  the  portion  of  the  Shelbyville  moraine  west  of  the  Illinois  River 
there  are  several  wells  150  feet  or  more  in  depth  which  penetrate  a  blue  till 
until  the  level  of  the  base  of  this  drift  sheet  is  reached. .  In  places  its  depth 
is  more  than  100  feet,  and  seldom  does  it  fall  below  70  feet.  A  large  well 
was  dug  by  William  Dickison  on  the  crest  of  the  moraine  2J  miles  west  of 
Alta.  The  well  entered  blue  till  at  less  than  10  feet,  winch  continued  to  a 
depth  of  117  feet.  Here  a  very  bowldery  bed  4  feet  in  thickness  was 
passed  through,  under  which  a  bed  of  loess  was  found,  specimens  of  which 
were  examined  by  the  Avriter.  Beneath  the  loess  there  is  a  hard  pebbly 
claj-,  apparently  lUinoian  till,  alternating  with  sand  beds.  Gravel  con- 
taining water  was .  struck  at  a  depth  of  156  feet.  A  well  made  by  John 
Holmes,  jr.,  one-half  mile  west  of  Alta  obtained  an  abundance  of  water 
at  125  feet  in  gravel  Ijelow  till.  But  a  boring  made  for  John  Holmes,  sr., 
1  mile  east  of  Alta  failed  to  obtain  water,  though  it  reached  a  depth  of  370 
feet.  It  apparently  did  not  strike  rock,  but  terminated  in  a  fine  sand.  A 
bed  of  muck  with  -^^-ood  and  leaves  was  found  at  the  remarkable  depth  of 
245  to  247  feet.  The  sand  below  the  muck  is  perhaps  an  allu^nal  deposit 
of  pre-Illinoian  ag-e. 

In  the  -sdcinity  of  Dunlap  the  best  supply  of  water  is  obtained  at  100 
to  112   feet,  in   gravel   and  sand    associated  with  the   older   drift.     In  the 


208  THE  ILLINOIS  GLACIAL  LOBE. 

village  the  base  of  the  Shelbyville  drift  sheet  is  reached  at  fi5  or  70  feet, 
and  a  few  wells  are  obtained  at  this  depth.  A  well  at  Harrison  Harlan's,  2 
miles  south  of  Dunlap,  at  a  level  about  40  feet  lower  than  the  village,  has 
a  depth  of  117  feet.  It  is  mainlj^  through  the  older  drift,  which  is  largely 
till,  and  Avater  is  obtained  in  sand  and  gravel  at  the  bottom. 

CHARACTER    OF    THE    OtTTWASH. 

Considerable  attention  has  been  given  the  deposits  and  valley  terraces 
immediately  outside  this  drift  sheet  and  on  its  outer  slope  in  order  to  ascer- 
tain the  character  of  the  outwash.  It  is  found  that  silt  deposits,  as  well  as 
sand  and  gravel,  cap  the  surface  of  the  outer  face  of  the  moraine  and 
extend  out  onto  the  border  plain.  Tlie  silt  depo.sits  are  loess  like  and  fos- 
siliferous,  and  suggest  a  feeble  drainage.  The  sand  and  gravel  deposits  are 
very  limited  in  tlieir  extent,  and,  on  the  whole,  favor  the  view  of  feeble 
drainage.  The  amount  of  coarse  outwash  is  very  much  less  than  is  found 
to  characterize  the  Bloomington  morainic  system,  as  is  shown  farther  on. 
In  some  portions  of  the  border  the  close  association  of  silt  and  gravelly  out- 
wash  renders  the  interpretation  somewhat  puzzling.  The  features  can  per- 
haps best  be  set  forth  by  giving  attention  to  each  valley  in  turn  which  leads 
away  from  the  Shelbyville  sheet  into  the  outer-border  district,  beginning 
with  the  Wabash  Valley  and  proceeding  westward. 

In  the  vicinity  of  the  Wabash  Valley  the  Shelbyville  drift  sheet  is 
found  to  be  generallv  coated  to  a  depth  of  several  feet  with  a  yellowish 
loess-like  silt.  This  is  especially  well  shown  on  the  west  side  of  the  valley 
in  the  vicinity  of  St.  Mary's,  Indiana.  This  silt  is  better  developed  on  the 
border  of  the  river  than  at  points  a  few  miles  back,  there  being  scarcelj^ 
enough  silt  in  the  latter  situation  to  conceal  the  bowlders  which  cap  the  till. 
The  distribution  of  the  silt  seems  such  as  would  be  expected  if  drainage 
conditions  Avere  inadequate  to  carry  off  the  water  from  the  melting-  ice. 
There  are,  however,  other  features  which  seem  to  indicate  good  drainage 
conditions.  At  the  point  where  the  moraine  crosses  the  river,  near  Ather- 
ton,  a  gravel  })laiu  is  liuilt  up  to  a,  height  of  about  75  feet  above  the  present 
stream,  whose  surface  carries  basins  such  as  occur  on  gravel  plaii\s  or  ter- 
races leading  awav  from  a  niorainc,  aud  -avv  found  ouIa"  near  the  moraine. 
Tliere  is  at  least  a.  suggestion  tltat  this  gravel  plain  is  to  l)e  correlated  with 
the   Shelbyville  moraine.     This  V\e\v  is  strengthened   1)}'  the  fact  that  the 


THE  SHBLBYVILLE  MOEAmE.  209 

material  is  very  coarse  at  this  point  compared  with  that  above  or  below, 
there  being  many  bowlders,  as  well  as  cobblestones,  embedded  in  the 
gravel.  Were  there  no  basins,  the  coarse  material  found  in  this  portion  of 
the  terrace  might  be  explained  as  a  product  of  subsequent  streams  working 
upon  the  portion  of  the  Shelbyville  moraine  which  had  been  laid  down 
within  the  valley,  but  the  basins  favor  the  view  that  this  portion  of  the 
terrace  is  the  product  of  the  headwaters  of  a  glacial  stream.  The  removal 
of  fine  material  from  this  terrace  seems  to  indicate  that  there  was  good 
drainage  at  the  time  it  was  forming,  a  view  which  does  not  readily  har- 
monize with  the  silt  deposition  along  the  valley. 

Passing  west  to  the  Embarras  Valley,  which  leaves  the  Shelbyville 
drift  near  the  line  of  Coles  and  Cumberland  counties,  one  finds  evidence  of 
a  moderate  discharge  of  water  down  the  valley.  The  outer  face  of  the 
moraine  contains  knolls  of  gravelly  constitution  in  the  immediate  vicinity 
of  the  Embarras  River,  and  among  these  knolls  there  are  plane-surfaced 
tracts  of  gravelly  material  having  the  appearance  of  being  the  dejjosit  of 
streams  issuing  from  the  ice  margin.  On  the  immediate  borders  of  the 
Embarras  Valley  there  is  still  better  evidence  of  glacial  outwash.  Gravel 
deposits  foi'm  a  sheet  which  caps  the  till  to  a  depth  of  several  feet  and  which 
declines  rapidly  from  the  crest  of  the  main  ridge  southward  to  the  plain 
outside  the  moraine,  occupying  a  very  shallow  valley  in  the  passage  down 
the  slope  of  the  moraine.  Remnants  of  this  gravel,  preseiwed  along  the 
brow  of  the  bluffs,  stand  90  feet  above  river  level  at  the  northernmost  point 
noted  (2  miles  north  of  the  county  line),  and  but  70  feet  opposite  the  ford 
at  the  county  line,  and  45  feet  at  the  south  edge  of  the  moraine  about  2 
miles  farther  south,  and  35  feet  above  the  river  at  the  oxbow  curve  a  mile 
farther  south.  The  rate  of  descent  is,  therefore,  about  10  feet  to  the  mile 
more  rapid  than  that  of  the  present  stream.  At  the  north  the  gravel  over- 
wash  stands  35  feet  above  the  level  of  the  base  of  the  Shelbyville  drift 
sheet,  whose  limits  are  here  well  defined  by  a  white  clay  such  as  caps  the 
older  drift  outside  the  Shelbyville  sheet.  At  the  south  border  of  the  Shel- 
byville drift  the  surface  of  the  gravel  stands  25  feet  below  the  level  of  the 
white  clay;  it  therefore  cuts  right  down  across  the  plane  of  the  white  clay. 
The  valley  of  the  Embarras  above  the  south  edge  of  the  Shelbyville  sheet 
has   probably  been    excavated    entirely  since    the    Shelbyville   drift  was 

MON  XXXVIII 14 


210  THE  ILLINOIS  GLACIAL  LOBE. 

deposited.  The  depth  of  the  gravel  deposits  on  the  outer  face  of  the  Shel- 
byville  moraine  is  but  a  few  feet,  seldom  so  much  as  15  feet,  and  the 
gravelly  belt,  including  the  knolls  as  well  as  plane-surfaced  tracts,  has  a 
width  of  scarcely  more  than  2  miles.  The  gravel  has  been  carried  but  a 
few  miles  south  of  the  limits  of  the  moraine,  there  being  only  sand  from 
the  vicinity  of  Greenup  southward  in  the  terrace  remnants  found  along  the 
valley.  These  terrace  remnants  stand  20  to  40  feet  below  the  border 
ujjlands  and  have  apparently  been  built  up  at  least  from  the  level  of  the 
stream,  25  feet  or  more.  The  moderate  transportation  of  gravel  seems  to 
indicate  that  the  discharge  was  not  vigorous  and  that  drainage  conditions 
were  rather  imperfect,  except  on  the  slope  of  the  moraine. 

Passing  westward  to  the  Kaskaskia  Vallej^,  which  leaves  the  Shelby- 
ville  drift  at  the  city  of  Shelbyville,  one  finds  that  the  valley  below  the 
border  of  the  moraine  contains  scarcely  any  deposits  coarser  than  sand  in 
the  terraces  built  up  during  the  Shelbyville  or  later  stages.  Light  deposits 
of  gravel  were  found  on  small  tributaries  at  the  points  where  they  leave  the 
Shelbyville  drift  sheet,  but  these  are  only  a  few  feet  in  depth  and  are  not, 
as  a  rule,  continued  down  to  the  river  valley.  Within  the  limits  of  the 
moraine  immediately  above  Shelbyville  there  is  a  terrace  standing  about  25 
feet  above  the  river  which  contains  gravel  and  cobble.  In  places  the  gravel 
and  cobble  are  found  to  rest  upon  till  and  to  have  a  depth  of  but  8  or  10 
feet.  In  other  places  the  gravel  apparently  extends  to  the  underlying  shale, 
which,  as  shown  by  the  bridge  piers  east  of  Shelbyville,  sets  in  at  15  or  20 
feet  below  low  water.  It  is  not  entirely  clear  that  this  gravel  and  cobble 
was  formed  as  an  outwash  from  the  ice  sheet  at  the  Shelbyville  stage.  On 
the  contrary,  it  seems  quite  as  probable  that  it  is  a  residue  resulting  from 
the  cutting  down  of  the  valley  since  the  Shelbyville  stage.  In  the  process 
of  cutting  down,  the  coarse  material  would  become  concentrated  while  the 
fine  material  would  be  transportod  down  the  valley.  In  liarmony  with 
this  view  it  is  found  that  the  surface  of  the  terrace  is  somewhat  below  the 
level  of  the  Shelbyville  drift  sheet  and  occupies  a  valley  cut  in  that  and  the 
older  drift  sheet.  The  evidence  from  this  valley,  therefore,  indicates  a 
fee])le  outwash  from  the  ice  sheet  at  the  Shelbyville  stage. 

The  next  valley  of  importance  leading  away  from  the  Shelbyville  drift 
sheet  is  that  of  the  Sangamon  River.     Along  this  valley  from  the  edge  of 


THE  SHELBY VILLE  MORAINE.  211 

the  Shelbyville  sheet  down  as  far  as  Springfield  the  terraces  are  composed 
of  a  gravelly  sand  with  a  few  large  pebbles.  It  is  not  certain,  however, 
that  these  terraces  should  be  correlated  with  the  Shelbyville  drift  sheet,  for 
they  seem  to  be  quite  as  well  developed  above  the  point  where  the  river 
leaves  the  moraine  as  they  do  below  that  point.  As  indicated  farther  on, 
these  deposits  may  be  correlated  with  the  Cerro  Grordo  moraine.  At  the 
point  where  the  river  crosses  the  Shelbyville  moraine,  south  of  Decatur, 
and  also  south  of  Harristown,  the  terrace  remnants  are  found  to  lie  in  a 
valley  cut  to  considerable  depth  into  the  Shelbyville  sheet,  and  no  over- 
wash  gravels  were  found  at  higher  levels.  It  should  be  stated,  however, 
that,  owing  to  the  absence  of  wagon  roads  following  along  the  valley  and 
the  inclemency  of  the  weather  at  the  time  the  writer  was  there,  the  valley 
was  examined  only  at  the  two  road  crossings  south  of  Decatur  and  south  of 
Harristown.  Further  study  at  intermediate  points  or  below  Harristown 
may  bring  to  light  gravels  which  can  be  con-elated  definitely  with  the 
Shelbyville  moraine. 

Along  the  valley  of  Salt  Creek,  the  first  stream  of  importance  issuing 
from  the  Shelbyville  moraine  north  of  the  Sangamon  River,  a  light  deposit 
of  gravel  was  found  immediately  outside  the  moraine  on  the  road  between 
Kenne}^  and  Hallsville,  but  the  main  deposits  of  the  terraces  along  the 
valley  are  sand.  This  stream,  like  the  Kaskaskia  and  Embarras,  seems, 
therefore,  to  have  carried  only  a  weak  discharge  at  the  time  the  Shelby^dlle 
moraine  was  forming. 

Two  tributaries  of  Salt  Creek — Kickapoo  Creek  and  Sugar  Creek — 
which  cross  the  Shelbyville  moraine  farther  north  than  the  main  creek, 
have  their  sources  in  the  Bloomington  morainic  system  and  carry  terraces, 
whose  head  is  found  in  that  moraine.  The  valleys  were  not  given  sufficient 
study  to  enable  the  writer  to  determine  whether  they  also  have  terraces 
which  may  be  connected  with  the  Shelbyville  moraine.  If  such  terraces 
are  present,  they  are  far  less  conspicuous  than  those  which  head  in  the 
Bloomington  moraine. 

On  the  Mackinaw  River  a  terrace  has  been  traced  into  connection  with 
the  Bloomington  drift  sheet,  but  none  has  been  found  which  can  be  corre- 
lated with  the  Shelbyville.  A  deposit  of  loess  several  feet  thick  caps  the 
Shelbyville  moraine  in  the  interval  between  the  Mackinaw  and  Illinois 


212  THE  ILLINOIS  GLACIAL  LOBE. 

rivers,  aud  also  farther  nortli  and  south,  which,  as  above  noted,  seems  to 
have  been  derived  from  the  Shelbyville  drift  rather  than  brought  by  wind 
from  the  plain  of  lowan  loess  on  the  west. 

On  Farm  Creek,  which  enters  the  Illinois  River  opposite  Peoria,  and  on 
small  western  tributaries  of  the  Illinois  just  north  of  Peoria,  as  well  as 
on  the  borders  of  the  Illinois  Valley  in  the  vicinity  of  that  city,  there  are 
gravel  deposits  which  it  is  thought  are  derived  in  the  main  from  the  Bloom- 
ington  moraine,  though  some  of  the  deposits  west  of  the  river  may  prove 
to  be  connected  with  the  Shelbyville.  Those  along-  Farm  Creek  may  be 
traced  with  but  slight  interruption  eastward  into  connection  with  the  Bloom- 
ington  moraine.  These  gravel  deposits  have  a  remarkably  high  altitude 
above  the  Illinois  Valley,  their  elevation  being  about  175  feet  above  that 
sti-eam  on  each  side  of  the  Illinois  Valley  at  Peoria.  It  would  seem,  there- 
fore, that  the  Illinois  and  its  tributaries  have  been  cut  down  this  great 
amount  at  the  point  where  the  Shelbyville  moraine  crosses  the  river,  since 
the  Shelbyvalle  stage,  and  probably  since  the  Bloomington.  However,  the 
valley  was  apparently  filled  here  to  a  greater  height  than  at  points  above 
and  below.  A  view  of  the  gravel  at  Peoria  is  given  in  PI.  XIII.  It  is  of 
medium  coarseness,  and  in  this  respect  harmonizes  with  that  usually  found 
in  terraces  that  head  in  the  Bloomington  morainic  system.  It  is  coarser 
than  is  commonly  displayed  by  the  terraces  that  head  in  the  Shelbyville 
diiffc  sheet. 

Kickapoo  Creek  and  its  tributaries,  which  lead  away  from  the  Shelby- 
ville moraine  in  northern  Peoria  County,  have  terraces  of  sandy  gravel 
which  are  doubtfully  refeiTed  to  the  Shelbyville  stage.  They  may  prove 
to  be  simply  incidents  in  the  cutting  down  of  the  valleys  through  the  some- 
what sandy  drift  deposits  outside  the  Shelbyville  moraine.  There  appears 
to  be  no  gravel  teiTace  along  Kickapoo  Creek  that  can  be  correlated  with 
the  Bloomington  moraine,  though  the  stream  heads  in  that  moraine. 

In  view  of  the  evidence  just  cited  concerning  the  character  of  the  out- 
wash,  it  appears  that  in  general  it  was  weak,  and  it  is  doubtful  if  a  vigorous 
outwash  at  any  point  can  be  proved. 


THE  SHELBY  VILLE  MORAINIC  SYSTEM.  213 


INNER-BORDER  TRACT. 
TOPOGRAPHY. 


The  topography  for  some  distance  north  and  east  from  the  border  of 
the  Shelbyville  drift  is  of  a  gently  undulating  type,  not  markedly  different 
from  that  of  the  thickened  border.  North  and  west  from  the  Sangamon 
River  there  is  a  triangular  tract  included  between  the  Shelbyville  and 
Bloomington  moraines  in  which  swells  10  to  30  feet  high  are  not  uncom- 
mon, but  no  well-defined  morainic  belt  has  been  found.  East  from  the 
Sangamon  River  there  are  several  small  drift  ridges  lying  between  the  Shel- 
byville and  Bloomington  moraines,  but  the  greater  part  of  the  surface  is 
plane.  Aside  from  the  ridges,  the  surface  is  les?  undulating  than  in  the 
tract  west  of  the  Sangamon,  just  mentioned.  These  ridges  are  discussed 
individually  and  in  some  detail  farther  on. 


THICKNESS    OF    DRIFT. 


The  Shelbj^ville  till  sheet  covers  this  inner-border  tract  to  a  depth  gen- 
erally of  50  or  75  feet,  and  in  places  100  feet  or  more.  The  depth  seldom 
falls  below  50  feet.  It  is  usually  not  difficult  to  ascertain  the  thickness  of 
the  Shelbyville  sheet,  for  well  drillers  report  that  it  is  much  easier  to  pene- 
trate than  the  underlving*  older  drift.  In  •  the  detailed  discussion  which 
follows,  these  differences  are  set  forth. 

STRUCTURE    OF    DRIFT. 

In  the  district  west  of  the  Illinois  River  the  Shelbyville  moraine  is 
separated  from  the  Bloomington  moraine  by  a  narrow  lowland,  nowhere 
more  than  3  miles  in  width,  and  running  to  a  point  in  northern  Peoi'ia 
County  and  also  at  the  border  of  the  Illinois  Valley.  Apparently  the  drift 
beneath  this  lowland  is  mainly  till  and  has  considerable  depth,  one  well 
having  gone  down  218  feet  without  entering  rock.  The  well  referred  to  is 
located  oil  the  farm  of  John  Miller,  4  miles  north  of  Dunlap.  The  well 
driller  reports  that  the  upper  69  feet  was  a  soft  till,  mainly  of  blue  color, 
and  probably  to  be  referred  to  the  Shelbyville  drift  sheet.  The  remainder 
was  a  hard,  brownish-gray  till,  apparently  Illinoian. 


214  THE  ILLINOIS  GLACIAL  LOBE. 

Passing-  to  the  east  side  of  the  IlUnois,  we  find  the  Shelbyville  and 
Bloomington  moraines  closely  associated  at  the  east  bluff  of  the  inver,  but 
becoming  separated  within  a  few  miles  southeast  to  a  distance  of  10  or  12 
miles.  An  interval  of  this  width  separates  them  from  the  Mackinaw  River 
southeastward  to  Kickapoo  Creek,  near  the  meridian  of  Bloomington.  The 
Shelbyville  moraine  there  turns  south  and  the  Bloomington  moraine  turns 
east,  thus  leaving  a  wider  interval  between  the  two  morainic  systems.  In 
the  remaining  75  miles  from  the  meridian  of  Bloomington  eastward  to  the 
Indiana  line  the  interval  between  these  morainic  systems  is  40  to  60  miles. 
This  interval,  however,  as  stated  above,  is  not  entirely  occupied  by  a  plain, 
but  is  crossed  by  several  diift  ridges,  which  form  the  Champaign  morainic 
system  and  the  Cerro  Grordo  moraine,  and  these  ridges  are  found  mainly 
east  of  the  Sangamon  River.  A  wide  tract  west  of  that  stream  has  a 
generally  plane  surface,  with  only  occasional  swells,  and  these  but  10  to  30 
feet  or  less  in  height. 

This  tract  included  between  the  Shelbyville  moraine  on  the  west,  the 
Bloomington  moraine  on  the  north,  and  the  Sangamon  River  Valley  on  the 
east,  is  underlain  by  a  very  thick  deposit  of  drift.  Records  of  several  wells 
which  penetrate  more  than  200  feet  were  obtained,  and  it  is  probable  that 
the  average  thickness  of  drift  exceeds  200  feet  throughout  the  entire  ti-act. 
The  following  represent  the  deepest  wells  of  which  records  were  obtained. 

At  the  village  of  Morton  the  waterworks  well  terminates  in  sand  at  a 
depth  of  230  feet,  and  three  other  wells  within  2  miles  northwest  have  about 
the  same  depth,  and  none  reach  the  rock.  The  engineer  at  the  waterworks 
states  that  for  about  100  feet  the  di'ift  is  soft  and  easily  penetrated,  and  is 
mainly  of  blue  color.  This,  presumably,  is  the  dejith  of  the  Shelbyville 
drift  sheet.  The  next  100  feet  is  mostly  a  hard,  gray  till,  though  a  bed  of 
sand  20  feet  in  depth  is  included.     The  lower  30  feet  is  white  sand. 

At  Hopedale,  12  miles  south  of  Morton,  near  the  inner  border  of  the 
Shelbyville  moraine,  a  well  made  by  the  railway  compan}^  reached  a  depth 
of  195  feet.  It  was  mainly  till,  except  the  lower  35  feet,  which  was  a  fine 
sand.  A  bed  of  black  muck  was  passed  through  between  till  sheets,  but 
the  precise  depth  at  which  it  occurred  could  not  be  ascertained. 

In  southwestern  McLean  County  a  few  wells  have  reached  a  depth  of 
200  feet  without  entering  rock,  but  the  majorit}'  of  tubular  wells  are  75  feet 
or  less  in  depth.     The  Shelbyville  drift  sheet  apparentl}^  has  at  least  this 


THE  SHELBTVILLB  MOEAINIG  SYSTEM.  215 

depth  (75  feet),  for  the  wells  are  entirely  tlirough  soft  till  to  the  water- 
bearing gravel  near  the  bottom. 

In  the  vicinity  of  Heyworth  inflammable  gas  is  found  in  sand  at  depths 
ranging  from  155  to  214  feet.  The  strongest  well  is  located  on  the  farm  of 
J.  C  AVakefield,  three-fourths  of  a  mile  southeast  of  the  village,  and  has 
the  following  section,  reported  by  the  driller,  Mr.  Gault: 

Section  of  WakefieWs  gas  well  near  Heywortli,  Illinois. 

Feet. 

Till  (Shelbyville  sheet) 33 

Gravel  aucl  sand  (probably  Shelbyville) 69 

Hard  clay  ivitli  no  pebbles  or  grit 36 

Sand 15 

Hard  blue  clay 35 

Hard  clay  Tvitb  no  grit 11 

Black  muck 2 

Hard  gray  clay  without  grit 13 

Sand  and  gravel  with  gas. 

Total  depth 214 

When  the  gas  was  struck,  sand  and  gravel  were  blown  out  of  the 
mouth  of  the  well,  and  the  well  now  has  a  pressure  of  22  pounds  to  the 
square  inch  fromi  a  2-inch  pipe,  and  supplied  fuel  for  200  stoves  during 
the  winter  of  1896-97. 

At  Wapella,  a  village  6  miles  south  of  Heyworth,  the  deep  tubular 
wells  penetrate  about  80  feet  of  soft  blue  till  referable  to  the  Shelbyville 
di-ift  sheet.  Beneath  the  blue  till  is  a  bed  of  black  muck,  probably 
Peorian,  with  a  green  clay,  apparently  a  swamp  subsoil,  underlying  it. 
This  is  perhaps  an  lowan  silt.  Beneath  the  green  clay  is  a  hard  bowlder 
clay,  referred  to  the  lUiuoian.  Many  of  the  wells  are  obtained  at  the  base 
of  the  Shelbyville  sheet  at  65  to  80  feet.  Those  which  reach  a  greater 
depth  obtain  their  supply  from  sand  associated  with  the  older  till,  and  the 
sand  not  infrequently  yields  a  considerable  amount  of  gas. 

At  Leroy,  in  southern  McLean  County,  the  waterworks  supply  is  from 
a  well  110  feet  deep,  which  obtains  its  water  from  sand  below  the' till  of 
the  Shelbyville  sheet.  Wells  are  occasionally  sunk  in  that  ^dcinity  to  a 
depth  of  nearly  200  feet  and  penetrate  a  large  amount  of  sand  in  the  lower 
portion. 

At  Farmer  City  the  waterworks  supply  is  from  a  well  176  feet  in  depth 
which  does  not  reach  the  rock.     It  is  mainly  tlu-ough  till,  but  there  are 


216  THE  ILLINOIS  GLACIAL  LOBE. 

several  beds  of  sand  and  gravel  associated  with  it.     A  prospect  boring  for 
coal  made  at  this  city  penetrated  189  feet  of  drift,  as  follows: 

Section  of  boring  for  coal  at  Farmer  City,  Illinois, 

Teet. 

Blacksoil 2 

Yellow  till... 9 

Blue  till 36 

Sand  and  water 2 

Blue  till ; 21 

Saud  and  gravel 40 

Blue  clay 6 

Sand  and  gravel 8 

Sandy  blue  clay 40 

Sand  and  gravel 23 

Blue  clay 2 

Total  drift - 189 

Several  interesting  well  sections  and  bluff  exposures  are  found  along 
the  west  side  of  the  Sangamon  River  below  Mahomet.  About  1^  miles 
southwest  of  this  -sdllage,  in  sec.  16,  T.  20,  R.  7  E.,  the  river  exposes  in  its 
northwest  bluff  a  bed  of  peat  under  the  Shelbyville  till  sheet.  The  expo- 
sure is  several  rods  in  length  and  the  section  is  as  follows: 

Exposure  in  hluf  of  Sangamon  River  near  Mahomet,  Illinois. 

Feet. 

Yellow  till  with  gravelly  places  near  base,  where  sjirings  issue 10-12 

Gray  till  with  yellowish  tiuge 20 

Peat,  earthy  except  3  to  6  inches  at  top 2 

Gray  earthy  subsoil,  exposed 2-3 

Total,  to  river  bed 36 

It  is  probable  that  the  Shelbyville  sheet  is  reduced  at  this  place  to  a 
thickness  of  only  30  to  32  feet,  as  the  altitude  near  tlie  river  is  slig-htly 
lower  than  the  general  level  of  the  border  jjlains.  Wells  between  this 
exposure  and  Mahomet  pass  through  a  black  muck  or  peat  at  about  the 
same  level  as  that  exposed  along  the  river.  One  on  the  farm  of  James 
Lester  strikes  it  at  36  feet,  and  one  at  the  residence  of  D.  McAi-thur  at  42 
feet.  Mr.  McArthur'swell  was  continued  to  a  depth  of  100  feet  and  ^^ene- 
trated  a  harder  till  below  the  black  muck  than  that  which  overlies  it.  There 
are  places  between  this  exposure  and  Mahomet  where  the  entii'e  bluff  is 
composed  of  gravel.  It  is  principally  on  the  farm  of  Mr.  Lester,  and  lie 
has  tested  its  extent  by  means  of  borings  and  found  that  it  underlies  only 
60  acres.  Around  the  gravel  on  all  sides  except  at  the  southeast,  where  it 
fronts  the  river,  there  is  till.     Its  dejith  is  found  to  reach  50  or  60  feet  in 


THE  SHELBYVILLE  MORAINIC  SYSTEM.  217 

places.  Its  surface  lias  about  the  same  altitude  as  the  bordering  till  plain, 
35  feet  above  the  Sangamon  River. 

At  Dalton  City,  located  about  12  miles  southeast  of  Decatur,  the  bot- 
tom of  the  Shelbyville  drift  sheet  is  found  at  65  feet,  and  wells  have  been 
sunk  to  a  depth  of  150  feet  without  reaching  rock.  The  majority  of  wells 
are  about  70  feet.  It  is  not  uncommon  to  find  beds  of  black  muck  below 
the  Shelbyville  drift  in  the  ^acinity  of  this  village. 

At  Bethany,  5  miles  southeast  of  Dalton  City,  the  Shelbyville  sheet  is 
apparently  only  40  feet  in  depth.  At  this  depth  a  greenish  clay,  associated 
in  places  with  a  black  mucky  soil,  is  usually  entered.  This  clay  is  but  a 
few  feet  in  depth,  and  is  probably  an  lowan  silt.  It  is  underlain  by  a  hard 
gray  till,  called  hardpan,  which  seems  to  be  lUinoian.  The  tubular  wells 
in  that  vicinity  range  in  depth  from  70  to  140  feet  without  striking  rock. 

At  Sullivan  the  drift,  as  shown  by  records  published  in  the  Geology  of 
Illinois,  has  a  depth  of  about  200  feet.  The  public  water  supply  is  from 
wells  100  to  126  feet  in  depth.  The  mayor  reports  that  the  upper  50  feet 
is  a  soft  blue  till,  beneath  which  considerable  sand  is  penetrated.  This  is 
underlain  by  a  hard  till  which  is  penetrated  40  feet  or  more  before  the  water- 
bearing gravel  is  reached. 

In  northern  Coles  County,  between  Humboldt  and  Fair  Grange,  wells 
are  60  to  120  feet  in  depth  without  reaching-  rock.  In  some  wells  a  hard 
gray  till  is  struck  at  about  50  or  60  feet.  The  overlying  till  is  soft  and 
probably  is  referable  to  the  Shelbyville  sheet.  At  Oakland,  in  northeast- 
ern Coles  County,  rock  is  entered  at  about  50  feet. 

At  Kansas,  in  western  Edgar  County,  rock  is  entered  at  80  feet  or  less. 
lu  a  few  cases  wells  have  struck  a  black  soil  at  about  30  feet,  which  is 
probably  just  below  the  Shelbyville  drift  sheet.  A  well  midway  between 
Kansas  and  Isabel  entered  rock  at  only  40  feet,  but  others  in  that  vicinity 
50  feet  or  more  in  depth  do  not  strike  rock.  In  the  eastern  part  of  Edgar 
County,  on  Clay's  Prairie,  rock  is  occasionally  struck  at  only  20  or  25  feet, 
and  is  extensively  exposed  along  Bruillett's  Creek,  in  eastern  Edgar  County, 
Illinois,  and  southern  Vermilion  County,  Indiana.  The  general  thickness 
of  the  di-ift  in  that  region  can  scarcely  exceed  40  feet. 

The  Indiana  district,  immediately  north  from  the  Shelbyville  moraine, 
has  generally  a  comparatively  thin  sheet  of  drift  on  the  uplands,  rock  often 
being  struck  at  50  feet  or  less,  but  in  the  preglacial  valle}"s  the  di'ift  may 


218  THE  ILLINOIS  GLACIAL  LOBE. 

exceed  150  feet  in  thickness.  As  there  are  several  moraines  crossing  this 
district  the  discussion  of  its  features  is  taken  up  in  connection  with  them  on 
later  pages 

CERRO   GORDO  MORAINE. 
DISTRIBUTION. 

The  CeiTo  Gordo  moraine  emerges  from  beneath  the  Champaign 
moraine  opposite  the  village  of  Mahomet,  in  Champaign  County,  and  fol- 
lows the  east  border  of  the  Sangamon  River  Valley,  at  a  distance  of  1  to  3 
miles  from  the  stream,  from  Mahomet  southward  to  CeiTO  Grordo,  a  village 
10  miles  east  of  Decatiu-.  It  there  swings  away  from  the  river,  and  is  dis- 
tinctly traceable  only  to  Laplace,  6  miles  south  of  Cerro  Gordo,  there 
being  for  a  few  miles  no  definite  continuation.  A  distinct  ridge,  however, 
appears  near  Humboldt,  in  northern  Coles  County,  which  is  supposed  to 
be  its  continuation.  This  ridge  is  traceable  in  a  general  eastward  course, 
but  with  slight  windings,  tlu'ough  southeastern  Douglas  and  central  Edgar 
counties. 

The  interval  between  the  Cerro  Gordo  and  Shelbyville  moraines  varies 
greatly  in  width.  Near  the  city  of  Paris  they  are  closely  associated ;  at 
Humboldt  they  are  separated  by  a  space  of  10  or  12  miles,  and  a  similar 
interval  is  found  opposite  Cerro  Gordo.  From  CeiTO  Gordo  northward 
the  ridges  pursue  divergent  courses,  so  that  opposite  Mahomet  they  are 
separated  by  a  space  of  25  or  30  miles. 

TOPOaBAPHIC   EXPRESSION. 

The  portion  of  the  moraine  between  Mahomet  and  Laplace  consists  of 
an  irregular  aggregation  of  drift  swells  and  short  ridges,  occupying  a  belt 
about  2  miles  in  average  width.  The  knolls  are  so  closely  aggregated  that 
very  little  plane  surface  is  found  among  them.  The  usual  height  is  10  to 
20  feet,  but  a  few  are  30  feet  or  more  above  bordering  low  ground.  The 
belt  is  sharply  in  contrast  with  the  level  tract  to  the  east,  and  has  on  the 
whole  a  stronger  expression  than  the  Shelbyville  moraine. 

The  portion  leading  eastward  from  Humboldt  presents  more  variation 
in  topography  than  the  portion  just  mentioned.  In  northern  Coles  and 
southeastern  Douglas  counties,  and  for  several  miles  in  western  Edgar 
County,  it  consists  of  a  smooth  till  ridge  one-half  mile  to  a  mile  in  width, 
with  a  relief  of  20  to  30  feet.     In  places  it  is  but  60  to  80  rods  wide,  and 


THE  CEREO  GORDO  MORAINE.  219 

stands  only  10  to  15  feet  above  the  border  plain.  The  ridge  is  nearly 
continuous  except  at  the  Embarras  River,  which  cuts  through  it  o^jposite 
Dora  Station.  In  Edgar  County  the  belt  has,  on  the  whole,  a  stronger 
expression,  though  there  is  not  so  continuous  a  ridge  as  in  Douglas  and 
Coles  counties.  There  are  several  small  ridges,  one-fourth  mile  or  less  in 
width  and  10  to  20  feet  in  height,  which  form  a  disjointed  chain  leading 
southeastward  from  Brocton  to  Paris.  Associated  with  these  there  are 
knolls  of  considerable  prominence.  A  cluster  in  sees.  15,  16,  and  17,  T.  14, 
R.  12  W.,  known  as  the  Blue  Mounds,  rise  50  or  60  feet  above  the  border 
plains.  An  isolated  knoll  in  sec.  32,  T.  15,  R.  13  W.,  is  about  50  feet  in 
height  and  occupies  perhaps  20  acres.  North  and  northwest  from  this 
knoll,  in  sees.  29  and  30,  several  knolls  rise  abruptly  to  a  height  of  20  or 
30  feet,  and  one  to  a  height  of  40  feet.  In  the  northeast  part  of  Paris  there 
is  a  ridge  leading  from  Sugar  Creek  southwestward  about  1 J  miles,  which 
is  30  to  60  feet  in  height  and  has  a  billowy  surface.  Its  width  is  40  to  60 
rods.  Probably  this  ridge  belongs  in  the  belt  under  discussion,  though  it 
is  slightly  out  of  line  with  the  belt  and  is  separated  from  it  by  a  plane  tract 
about  2  miles  in  width.  Toward  the  northeast  there  are  occasional  knolls 
as  far  as  the  State  line,  but  no  definite  ridge  or  chain  of  knolls  appears. 
The  well-defined  belt  terminates  at  the  Blue  Mounds. 

STKUOTUKE   OF   THE   DEIFT. 

Some  of  the  sharpe:-  knolls  of  the  moraine  contain  gravel  and  sand, 
especially  along  the  border  of  the  Sangamon  River  and  in  Edgar  County. 
There  is,  as  a  rule,  considerable  till  associated  with  the  gravel  and  sand, 
and  the  knolls  are  usually  underlain  by  a  sheet  of  till.  The  gentle 
swells  and  the  smooth  ridges  are  composed  more  larg-ely  of  till  than  those 
of  sharper  contour. 

The  majority  of  wells  along  this  belt  obtain  their  sujjply  at  a  level 
little,  if  any,  below  the  base  of  the  knolls  and  ridges  and  within  the  limits 
of  the  early  Wisconsin  drift  sheets.  A  few  pass  into  the  older  drift.  Very 
rarely  a  well  reaches  the  rock.  The  drift,  as  in  the  tract  outside  the  moraine, 
is  very  thick  in  Illinois  except  in  the  vicinity  of  the  State  line,  but  is  thin 
in  Indiana.  The  following  are  the  deepest  wells  of  which  records  were 
obtained : 

On  H.  H.  Hollis's  farm,  in  sec.  30,  T.  20,  R.  7  E.,  a  well  is  215  feet  in 


220  THE  illiin'OIS  glacial  lobe. 

depth,  and  on  B.  F.  Hollis's  farm,  in  sec.  31,  two  wells  are  190  feet  in  depth, 
without  reaching  rock.  The  drift  is  largely  a  blue  till  and  but  a  small  part 
is  thought  to  belong  to  the  early  Wisconsin.  It  is  described  to  be  mainly 
hard  till  below  a  depth  of  40  feet.  F.  Gr.  Seymoin-  has  a  well  in  sec.  6, 
T.  19,  R.  7  E.,  215  feet  in  depth,  which  is  similar  to  the  wells  on  the  Hollis 
farms. 

At  Monticello  the  city  water  supply  is  from  two  wells  212  and  303  feet 
in  depth,  neither  of  wliich  enters  rock.  The  early  Wisconsin  drift  here  is 
apparently  but  20  feet  thick,  the  wells  being  on  low  ground  near  the  San- 
gamon River.  The  following  is  the  record  of  the  deeper  well  as  published 
in  the  Piatt  Independent  soon  after  the  completion  of  the  well  in  1891: 

Section  of  a  waterworks  well  at  Monticello,  Illinois. 

Foet. 

Black  lo?m 3 

Yellow  clay 10 

Blue  clay  (gravelly) 7 

Brown  peaty  loam  (Peorianf) 7 

Sand  and  gravel 2 

Blue  clay 11 

Sand,  gravel,  and  water 5 

Silt 1-2 

Sand'  gravel,  and  water 55 

Hard  blue  clay  (pebbly  "bardpan  ") 49^ 

Quicksand - 75^ 

Sand  and  gravel 64 

Coarse  gravel 2 

Total 303 

In  the  A-eins  of  water  above  the  "hardpan"  the  water  is  less  suitable 
for  culinary  and  laundry  purposes  than  in  those  below,  because  of  greater 
hardness.  Both  wells  are,  therefore,  sunk  to  a  coarse  gravel  in  the  lower 
water  bed. 

At  Bement  a  well  in  the  business  23art  of  town  struck  rock  at  222  feet 
and  is  225  feet  in  depth.  Wells  at  the  waterworks,  the  railway  station,  and 
the  mill  obtain  a  good  supply  of  water  at  140  to  150  feet,  after  penetrating 
a  large  amount  of  blue  till.  It  is  not  certain  that  the  Wisconsin  di-ift  has 
so  great  a  depth  as  150  feet  at  this  point,  the  records  of  wells  being  imper- 
fect. At  the  cemetery,  2  miles  north  of  Bement,  near  the  crest  of  the  Cerro 
Gordo  moraine,  a  well  221  feet  in  depth  is  mainly  through  blue  till  and  does 
not  reach  rock. 

At  Cerro  Gordo  there  is  a  nearly  solid  bed  of  blue  till  to  a  depth  of 
150  feet,  and  strong  wells  are  seldom  obtained  at  less  depth.      That  the 


THE  CEREO  GORDO  MOEAINE.  221 

Wisconsin  diift  lias  a  depth  of  150  feet  at  tins  point  is  supported  by  the  fact 
that  the  moraine  there  reaches  an  altitude  nearly  150  feet  above  the  level 
of  the  buried  soil  along  the  Sangamon  Valley  at  Monticello  and  near 
Mahomet. 

Along  the  ridge  from  Humboldt  eastward  into  Douglas  County  wells 
apparently  reach  the  base  of  the  Wisconsin  drift  at  65  to  75  feet,  and  farther 
east  at  50  feet  or  less. 

The  sharp  ridge  situated  in  the  northeast  part  of  Paris  has  been  opened 
extensively  for  gravel.  There  is  at  the  surface  a  brownish  yellow  till  5 
to  15  feet  thick,  and  beneath  this  are  beds  of  calcareous  sand  several  feet 
in  depth.  Beneatli  the  sand  there  is  a  sandy  gravel.  Both  the  sand  and 
the  gravel  show  considerable  cross-bedded  structure.  The  beds  are  also 
arched,  and  appear  to  have  been  crumpled  somewhat  as  if  by  a  disturb- 
ance by  the  ice  sheet.  In  order  to  ascertain  the  proportion  of  the  various 
kinds  of  rock  in  this  gravel,  a  small  space  was  marked  off  in  the  gravel 
pit  and  the  pebbles  therein  were  classified,  with  the  following  result : 

Classification  of  pehhles  in  a  gravel  pit  at  Paris,  Illinois. 

Granite g 

Otlier  crystalline  rocks 8 

Quartz 3 

Chert  of  light  color 13 

BroTvn  chert 1 

Carboniferous  sandstone  (local) H 

Gray  limestone  (probably  local) '  45 

Magnesian  limestone 4g 

Total 1^ 

A  few  of  the  gray  limestone  pebbles  are  striated.  These  pebbles  show 
less  rounding  by  water  action  than  other  classes.  It  is  probable  that  some 
of  them  are  from  the  Carboniferous  limestone  exposed  near  Baldwinsville, 
north  of  Paris. 

CHARACTER   OF   THE   OUTWASH. 

The  character  of  the  outwash  from  the  Cerro  Grordo  moraine  has 
received  very  httle  attention.  It  has  been  noted,  however,  that  the  valleys 
leading  away  from  the  moraine,  with  the  exception  of  the  Sangamon,  are 
small  and  are  usually  cut  in  till.  There  can  not,  therefore,  be  very  heavy 
sand  or  gravel  outwash. 

Along  the  Sangamon  Eiver  for  a  few  miles  below  Mahomet  this 
morainic  belt  is  bordered  on  the  west  by  a  gravelly  plain,  whose  origin  and 


222  THE  ILLINOIS  GLACIAL  LOBE. 

relationships  are  not  fully  determined.  It  may  be  due  largely  to  the  cutting 
down  of  gravelly  portions  of  the  Shelbyville  sheet,  such  as  that  near 
Mahomet  just  noted.  It  stands  about  20  feet  above  the  Sangamon  River, 
or  about  halfway  from  the  level  of  the  river  up  to  the  level  of  the  till  plain 
on  the  west.  In  places  the  morainic  knolls  east  of  the  river  extend  down  to 
the  level  of  this  gravelly  plain,  and  seem  to  be  merged  with  it  so  intimately 
that  there  is  a  strong  suggestion  of  similarity  in  age.  However,  it  is  not 
fully  established  that  even  in  such  places  the  gravel  is  an  outwash  from  the 
moraine.  As  shown  below,  there  is  a  light  gravelly  outwash  near  Mahomet 
from  the  Champaign  moraine  over  the  till  plain  that  borders  it  on  the  south. 
It  is  possible  that  the  gravel  plain  along  the  valley  was  built  up  in  part  at 
that  time,  though  the  lightness  of  the  deposit  at  Mahomet  scarcely  warrants 
the  reference  of  a  large  part  of  the  filling  to  this  source. 

INNER  BORDER  TRACT. 

Between  the  Cerro  Grordo  moraine  and  the  outer  ridge  of  the  Champaign 
morainic  system  there  is  a  plain  whose  width  nowhere  exceeds  26  miles  and 
usually  is  about  12  or  15  miles.  This  plain  has  a  very  level  surface,  there 
being  few  swells  or  knolls  and  but  little  variation  in  altitude.  It  is  under- 
lain bv  thick  deposits  of  drift,  except  for  a  few  miles  near  the  State  line. 
Wells  indicate  that  it  may  average  nearly  200  feet,  of  which  probably  more 
than  one-half  is  older  than  the  Shelbyville  sheet.  Since  the  majority  of  wells 
obtain  water  without  reaching  the  base  of  the  Shelbyville  sheet,  few  data 
concerning  the  older  di'ift  are  available  from  this  region,  but  inferences 
may  be  drawn  to  some  extent  from  neighboring  districts  on  either  side, 
where  the  data  concerning  thickness  of  the  drift  are  more  full. 

Wells  in  the  ^-icinitv  of  Areola  are  reported  to  have  ^^assed  from  the 
s©ft  till  of  the  Shelbyville  sheet  into  a  harder  till,  presumably  of  the 
older  drift,  at  a  depth  of  only  45  or  50  feet.  In  the  vicinit}-  of  Tuscola 
the  wells  usually  pass  from  the  soft  till  of  the  Shelbyville  sheet  to  a  harder 
till,  termed  hardpan,  at  a  depth  of  35  to  40  feet.  A  prospect  boring  for 
coal  at  Tuscola  penetrated  186  feet  of  drift.  It  is  probable  that  the  thick- 
ness of  the  Wisconsin  drift  is  somewhat  greater  on  the  portion  of  the  plain 
to  the  west  of  these  towns,  as  shown  by  records  outside  the  Cerro  Grordo 
moraine  already  given.  The  thickness  to  the  east  of  these  villages  is  prob- 
'  ably  less  rather  than  greater  than  in  their  vicinity,  there  being  a  general 
decrease  in  thickness  in  that  direction. 


THE  EARLY  WISOONSIN  DRIFT  SHEETS.  223 

SECTION  II.     CHAMPAIGN  MOEAINIC  SYSTEM. 

Under  this  head  is  discussed  a  group  of  closely  associated  ridges  which 
interlock  to  some  extent,  but  usually  consist  of  two  or  three  distinct  mem- 
bers. The  system  receives  its  name  from  the  city  of  Champaign,  Illinois, 
the  site  of  the  State  University.  The  ridges,  which  are  more  or  less  dis- 
tinct east  from  this  city,  become  united  in  a  single  ridge  from  this  city 
westward.  The  discussion  begins  at  the  westernmost  point  at  which  the 
system  has  been  recognized,  and  proceeds  eastward  to  the  point  of  disap- 
pearance beneath  a  morainic  system  of  late  Wisconsin  age.  In  the  com- 
plex portion  separate  names  have  been  applied  to  the  several  members,  viz, 
Outer  or  West  Ridge,  Middle  Ridge,  and  Inner  Ridge 


DISTRIBUTION. 


The  westernmost  prominent  development  of  the  Champaign  morainic 
system  is  found  in  "  Blue  Ridge,"  which  sets  in  near  the  village  of  Blue 
Ridge,  in  northern  Piatt  County,  and  leads  southeastward  into  Champaign 
County.  There  is,  howevqr,  a  narrow  belt,  with  rather  more  undulation 
than  is  common  on  till  plains,  which  leads  westward  from  near  the  north 
end  of  Blue  Ridge  past  Leroy  to  the  Bloomington  moraine  at  Downs,  and 
which  is  doubtfully  referred  to  the  Champaign  morainic  system.  This 
undulatory  belt  stands  20  to  30  feet  or  more  above  the  general  level  of  the 
plain  on  the  south,  but  the  rise  is  so  gradual  that  the  relief  is  scarcely 
perceptible. 

The  portion  known  as  Blue  Ridge  comes  to  the  Sangamon  River  just 
above  Mahomet.  With  a  gap  scarcely  one-half  mile  wide  the  moraine 
reappears  on  the  east  bluff,  and  leads  southeastward  to  Champaign,  crossing 
the  Cleveland,  Cincimiati,  Chicago  and  St.  Louis  Railway  west  of  the  city. 
The  width  from  Blue  Ridge  to  Champaign  averages  about  2  miles. 

A  short  distance  west  of  Champaign  the  Outer  or  West  Ridge  sepa- 
rates from  the  main  belt  and  passes  southward  through  Savoy  and  Tolono 
to  West  Ridge  village,  in  Douglas  County,  near  which  it  swings  rapidly 
eastward  and  joins  the  middle  member  of  the  series  in  southwestern  Ver- 
milion County.  This  ridge  has  an  average  breadth  of  scarcely  one-half 
mile  in  its  north-south  portion,  but  in  the  west-east  portion  it  increases  to 
a  width  of  nearly  2  miles  and  becomes  the  principal  i-idge  of  the  series. 


224  THE  ILLINOIS  GLACIAL  LOBE. 

From  Champaign  a  ridge  nearly  as  bulky  as  the  combined  belt  leads 
southeastward  through  Philo.  A  short  distance  southeast  of  this  village  it 
separates  into  two  quite  distinct  ridges.  One  continues  the  southeast  course 
past  Broadland  and  joins  the  outer  ridge  in  southwestern  Vermilion  County. 
The  inner  ridge  passes  eastward  into  Vermilion  County  along  a  line  nearly 
parallel  with,  and  about  2  miles  south  of,  the  Wabash  Railway  until  it 
reaches  the  meridian  of  Fainuount,  where  it  turns  southeastward.  It  comes 
to  Little  Vermilion  River  east  of  Georgetown  and  follows  the  north  side  of 
that  stream  to  the  Wabash  Valley.  East  of  the  Wabash  its  course  is  north- 
eastward to  Veedersburg,  and  thence  eastward  into  western  Montgomery 
County,  where  it  is  overridden  by  a  late  Wisconsin  moraine  and  its  further 
course  lost  to  \aew.  This  ridge  throughout  its  entire  length  is  naiTow  and 
low,  seldom  exceeding  one-half  mile  in  width,  and  rising  but  a  few  feet 
above  border  plains.  It  is  also  scarcely  so  continuous  as  the  other  mem- 
bers of  the  series.  From  Veedersburg  another  weak  drift  ridge  leads 
northward  past  Rob  Roy  to  the  Wabash  Valle}^  near  Attica,  beyond  which 
it  can  not  be  traced,  because  of  concealment  beneath  later  moraines. 

Returning  to  southwestern  Vermilion  County,  where  the  Middle  and 
Outer  ridg'es  become  united,  and  tracing  theii"  further  course,  one  finds  a 
ridge  about  2  miles  wide  and  60  to  100  feet  high  passing  eastward  near  the 
line  of  Vermilion  and  Edgar  counties  into  Indiana.  In  places  it  has  a 
double  crest,  but  in  other  places  it  is  a  thoroughly  combined  belt.  For  a 
few  miles  on  the  west  side  of  the  Wabash  River  it  is  not  well  defined,  but 
it  is  easily  located  on  the  east  bluff  just  below  the  mouth  of  Sugar  Creek. 
Its  course  for  about  8  miles  is  south  of  east.  It  there  curves,  near  the 
village  of  Bloomingdale,  and  takes  a  nearly  northeast  course,  crossing 
Sugar  Creek  at  a  narrow  gorge  known  as  "  The  Shades  of  Death"  near  the 
line  of  Parke  and  Montgomery  counties.  In  western  Montgomery  County 
near  the  village  of  Alamo,  which  stands  on  its  crest,  the  course  is  again 
changed  toward  the  north,  and  it  trends  nearly  due  north  to  where  it  is 
oveiTidden  by  a  moi'aine  of  the  late  Wisconsin  series,  near  Wesley,  Indiana. 

The  course  of  the  members  of  the  Chamjiaign  system  is  such  tliat  the 
Inner  Ridge  is  separated  from  the  combined  ]\Iiddle  and  Outer  belt  by  a 
space  15  to  20  miles  in  width  in  the  district  immediately  east  of  the 
Wabash,  while  west  from  that  valley  the  space  is  10  miles  or  less.     The 


THE  CHAMPAIGN  MORAINIO  SYSTEM.  225 

Outer  Ridge  at  its  widest  separation  from  the  Middle  one  is  distant  but  8  or 
9  miles.  It  is  separated  from  the  Middle  Ridge  for  only  about  30  miles  of 
the  100  or  more  miles  in  which  they  are  exposed  to  view.  The  Inner 
Ridge  is  distinct  from  the  others  for  a  much  longer  distance,  being  combined 
with  them  for  only  about  30  miles  of  the  100  which  the  belt  occupies. 

It  will  be  observed  that  the  moraines  are  looped  across  the  Wabash 
Basin  after  the  fashion  of  the  looping  of  the  late  Wisconsin  moraines  about 
the  basins  and  large  valleys,  as  brought  to  notice  by  Chamberlin  in  the 
Third  Annual  Report  of  this  Survey.  The  axis  of  the  Wabash  Basin  is 
depressed  only  150  to  200  feet  (aside  from  the  immediate  valley  of  the 
river)  below  the  borders  of  its  watershed  where  crossed  by  this  morainic 
system.  This  slight  amount  of  depression  seems  scarcely  adequate  to  be 
the  sole  cause  for  the  protrusion  of  the  ice  sheet  into  the  valley,  though  it 
no  doubt  had  some  influence. 

EELIBF. 

The  relief  of  the  combined  belt  between  Blue  Ridge  and  Champaign 
reaches  about  90  feet  above  the  outer-border  plain  at  several  points,  though 
it  usually  is  about  60  to  75  feet.  The  outer-border  plain  declines  from  750 
feet  at  Blue  Ridge  to  about  710  or  720  feet  east  of  the  Sangamon.  The 
crest  of  the  moraine  reaches  820  feet  in  northern  Piatt  County,  and  800  to 
810  feet  near  Rising  in  Champaign  County,  but  averages  only  about  775 
feet  above  tide.  The  inner-border  plain  lying  north  of  this  portion  of  the, 
moraine  stands  about  730  feet  above  tide. 

The  outer  ridge  has  a  measured  relief  of  45  feet  on  the  outer  border 
and  40  feet  on  the  inner  border  at  the  crossing  of  the  Wabash  Railway  at 
Tolono,  but  at  the  crossing  of  the  Chicago  and  Eastern  Illinois  at  West 
Ridge  it  scarcely  exceeds  35  feet  on  either  border.  Farther  east,  near  its 
junction  with  the  Middle  Ridge,  the  relief  increases  to  70  feet,  and  one 
point  near  Palermo,  used  by  the  United  States  Lake  Sxirvey  as  a  site  for  a 
geodetic  station,  stands  90  feet  above  the  general  level  of  the  outer  border 
plain. 

The  Middle  Ridge  has  a  relief  of  25  or  30  feet  on  its  outer  border 

tlu'oughout  the  interval  in  which  it  is  distinct  from  the  Outer  Ridge.     On  its 

inner  border  the  relief  is  about  20  feet.     At  Philo,  where  the  Inner  and 

Middle  ridges  are   combined,  the  outer-border    relief,    as   shown  by  the 

MON  xxxviii 15 


226  THE  ILLINOIS  GLACIAL  LOBE. 

Wabash  Railway  sui-ve}',  is  30  or  35  feet,  while  the  inner-border  relief  is 
about  50  feet.  The  relief  of  the  Inner  Ridge  throughout  its  entire  course 
in  Illinois  and  Indiana  is  but  15  to  20  feet,  except  where  knolls  rise  above 
the  general  level  of  the  crest.  In  such  cases  a  relief  of  40  or  50  feet  may 
be  foinid.  The  combined  Middle  and  Outer  ridge  has  a  general  relief  in 
eastern  Illinois  of  about  40  feet  above  the  outer-border  plain  and  about  the 
same  relief  above  the  inner  border.  Where  there  is  a  double  crest,  the  sag 
between  the  crests  is  15  to  25  feet  in  depth. 

In  the  Indiana  portion  the  relief  seldom  reaches  40  feet,  and  the  aver- 
age is  probablj  30  feet  above  the  plains  on  the  outer  and  inner  border. 

It  appears  from  the  data  just  given  that  the  outer  and  inner  border 
reliefs  in  this  morainic  system  are  not  markedly  different.  There  is  not 
such  a  filling  on  the  inner  border  and  transition  from  the  moraine  into  the 
plain  as  in  the  Shelbyville  or  Cerro  Gordo  moraines.  As  seen  in  profile,  the 
ridges  of  the  Champaign  system  rise  with  nearly  as  rapid  slope  on  the  inner 
as  on  the  outer  border,  a  feature  which  distinguishes  them  from  nearly  all 
of  the  moraines  of  the  Wisconsin  series,  it  being'  the  h?bit  of  the  Wisconsin 
moraines  to  present  a  long  inner  slope  and  a  somewhat  abrupt  outer  slope. 

KANGE    IN   ALTITUDE. 

As  indicated  above,  the  moraine,  near  the  western  end,  attains  an  alti- 
tude of  820  feet  above  tide,  while  the  border  plains  are  about  750  feet.  The 
altitude  of  the  plains  decreases  to  about  700  feet  in  southern  Champaign 
Coimtv  and  to  660  feet  in  the  vicinity  of  the  Embarras  River,  in  northern 
Douglas  County.  From  this  point  eastward  to  the  borders  of  the  Wabash 
the  plains  stand  650  to  675  feet  along  the  border  of  the  combined  Middle 
and  Outer  ridge.  The  altitude  is  less  uniform  along  the  line  of  the  Inner 
Ridge,  there  being  a  range  of  about  75  feet  in  the  Illinois  portion.  The 
liighest  part  of  the  plain  near  Sandusky  is  fully  720  feet  above  tide,  while 
in  the  western  part  of  the  county  it  scarcely  reaches  675  feet,  and  in  the 
eastern  it  falls  to  about  650  feet.  On  the  borders  of  the  Wabash  in  western 
Indiana  the  altitude  of  the  upland  plain  declines  to  about  600  feet.  There 
is  a  gradual  rise  from  the  valley  eastward  to  775  or  800  feet  in  western 
Montgomery  County,  where  the  moraines  of  this  system  pass  beneath  a 
moraine  of  the  late  Wisconsin  series. 


THE  CHAMPAIGN  MORAINIC  SYSTEM.  227 


SURFACE   CONTOURS. 


On  the  whole  the  ridges  of  this  system  are  of  a  type  which  may  best 
be  designated  the  smooth-ridge  type,  the  surface  undulations  being  very 
gentle,  while  the  crest  is  usually  well  defined.  A  detailed  examination, 
however,  brings  to  light  considerable  variation  in  the  features. 

The  portion  west  of  the  Sangamon  River,  known  as  Blue  Ridge,  has  a 
well-defined  crest,  along  which  undulations  of  10  to  20  feet  occur.  On  its 
slojDes  also  there  are  gentle  swells  5  to  15  feet  in  height.  In  the  vicinity  of 
the  Sangamon  River  a  few  knolls  of  greater  prominence  appear,  though  the 
highest  scarcely  rise  more  than  40  feet  above  bordering  low  ground. 
Between  the  Sangamon  River  and  Champaign  the  moraine  presents  a  well- 
defined  crest  and  undulatory  slopes.  The  undulations  commonly  fall 
below  20  feet,  both  along  the  crest  and  on  the  slopes.  The  outer  face  is 
more  abrupt  than  the  inner,  there  being  places  where  a  rise  of  50  feet  is 
made  within  a  mile  from  the  border  of  the  plain  outside  the  moraine. 

The  Outer  Ridge  from  the  city  of  Champaign  around  to  northeastern 
Douglas  County  has  a  very  smooth  surface,  in  which  undulations  seldom 
exceed  10  feet.  The  relief  of  20  to  40  feet,  however,  makes  the  ridge  a 
noticeable  feature.  In  passing  eastward  through  northern  Douglas  County 
the  ridge  becomes  much  larger,  but  maintains  a  nearly  smooth  surface.  A 
short  distance  west  of  its  jiinction  with  the  Middle  Ridge  it  jjresents  a 
double  crest,  but  each  ridge  is  very  smooth. 

The  belt  leading  southeast  from  the  city  of  Champaign  presents  swells 
15  feet  or  more  in  height,  but  the  crest  is  ill  defined  between  the  city  of 
Champaign  and  sec.  33,  Ui-bana  Township.  From  this  section  southeast- 
ward, through  Philo  Township,  and  thence  eastward  to  sec.  4,  Raymond 
Township,  the  crest  is  well  developed.  It  has  oscillations  of  from  10  to  25 
feet,  and  the  slopes  are  characterized  by  knolls  of  similar  elevation.  In  the 
vicinity  of  Lynn  Grrove  geodetic  station  knolls  and  sharp  winding  ridges 
30  or  40  feet  in  height  occur,  and  the  moraine  maintains  this  strength  of 
expression  for  about  3  miles  east  from  the  geodetic  station.  It  there  loses  , 
strength,  and  in  northeastern  Raymond  and  South  townships,  ChamjDaign 
County,  and  in  Sidell  Township,  Vermilion  County,  it  consists  of  a  smooth 
ridge  scarcely  20  feet  higher  than  the  plain  south  of  it.     North  of  this 


228  THE  ILLINOIS  GLACIAL  LOBE. 

ridge  there  are  scattering  knolls  surrounded  Ijy  -s-ery  level  tracts.  One 
knoll  near  the  line  of  sees.  1  and  2,  Raymond  Township,  co^"ers  not  less 
than  10  acres  and  has  a  height  of  probably  30  feet.  Other  knolls  10  to  25 
feet  in  height  were  observed.  The  Middle  Ridge  does  not  connect  closely 
with  the  Outer  Ridge  in  southeastern  Champaign  and  southwestern  Ver- 
milion counties,  but  is  separated  from  it  by  a  sag  or  depressed  tract  a  half 
mile  or  less  in  width.  This  depression  connects  on  the  east  with  the  Little 
Vermilion  River  and  on  the  west  with  the  Nile,  a  tributary  of  Emban-as 
River. 

For  about  5  miles  eastward  from  the  Palermo  geodetic  station  a  single 
broad  ridge,  IJ  to  2  miles  wide,  constitutes  the  equivalent  or  continuation 
of  the  two  ridges  found  farther  west.  It  does  not  long  continue  the  sole 
representative,  however,  for  another  ridge  sets  in  just  north  of  the  head- 
waters of  Bruillett's  Creek,  in  sec.  4,  T.  16,  R.  12  W.  From  this  section 
eastward  nearly  to  the  State  line  there  is  a  double  ridge,  tlie  members  of 
which  are  nowhere  separated  more  than  one-half  mile.  Mortimer  stands  on 
the  outer  and  Ridg-e  Farm  ^nllage  on  the  inner  of  these  ridges.  A  few  basins 
occur  along  the  ridges  in  southeastern  Vermilion  County,  the  deepest  of 
which  are  depressed  8  or  10  feet  below  bordering  land  and  are  occupied  by 
peat  bogs.  The  ridges  have  gentle  undulations  of  10  to  20  feet,  both  along 
the  crest  and  on  the  slopes.  The  Outer  Ridge  has  interruptions  or  gaps 
which  afford  a  passage  for  waters  which  fall  be'tween  the  two  ridges  south- 
ward to  the  outer-border  plain.  The  gap  through  which  Bruillett's  Creek 
passes  is  nearly  75  feet  in  depth  and  less  than  one-half  mile  in  width.  Sev- 
eral other  gaps  of  less  depth  occur,  all  of  which  are  quite  narrow.  They 
appear  to  have  been  deepened  considerably  b}'  the  streams  which  pass 
through  them.  The  two  ridges  become  coalesced  at  Pilot  Grove,  a  promi- 
nent point  in  sec.  33,  T.  17,  R.  11  W.  From  this  grove  eastward  to  the 
State  line,  knolls  and  ridges  rise  from  the  crest  and  slojDe  somewhat  al>ruptly 
to  heights  of  15  or  20  feet,  and  give  the  moraine  a  sharper  expression  than 
is  usually  dis])laYed.  From  the  State  line  eastward  to  the  Wabash  River 
the  l)idk  as  well  as  the  expression,  decreases,  the  crest  becomes  poorh" 
defined,  and  the  undulations  are  scarcely  10  feet  in  height. 

For  a  few  miles  east  of  the  Wabasli  River  the  moraine  is  represented 
by  knolls  only,  there  being  no  well-defined  ridge  or  crest  line.  The  most 
])rominent  knolls  observed  are  in  sec.  17,  Reserve  Town.shi]),  Parke  County. 


THE  CHAMPAIGN  MOKAINIC  SYSTEM.  229 

They  are  somewhat  elongated  in  a  NW.-SE.  chrection,  and  rise  abruptly 
to  a  height  of  20  or  30  feet.  Farther  east,  in  the  vicinity  of  Bloomingdale, 
the  knolls  are  in  some  cases  30  feet  or  more  in  height.  In  sees.  24  and  19, 
25  and  30,  T.  16,  Rs.  7  and  8  W.,  the  moraine  consists  of  a  ridge  80  rods 
to  a  mile  or  more  in  width,  on  whose  slopes  and  crest  knolls  10  to  25  feet 
in  height  are  numerous.  Outside  the  main  ridge  there  is,  in  sec.  29,  a  chain 
of  knolls  15  to  20  feet  high,  rising  abruptly  above  the  bordering  plane 
tract.  In  eastern  Parke  County  the  moraine  for  a  distance  of  about  10 
miles  constitutes  the  water  parting  between  Little  Raccoon  and  Sugar 
creeks,  and  there  is  scarcely  a  mile  of  this  portion  on  which  knolls  15  to  25 
feet  high  do  not  occur,  while  in  some  sections  they  reach  heights  of  30  or  40 
feet  These  knolls  stand  upon  a  basement  ridge  whose  relief,  independent 
of  the  knolls,  is  30  or  40  feet.  In  this  part  of  the  moraine  the  knolls  are 
arrai:iged  in  chains  trending  parallel  with  the  crest.  In  southwestern  Mont- 
gomery County,  on  the  south  side  of  Sugar  Creek,  there  are  numerous 
sharp  knolls  in  the  moraine,  but  not  a  distinct  ridging  or  well-defined  crest. 
North  of  Sugar  Creek  the  moraine  assumes  a  ridged  form  near  the  south 
line  of  sec.  34,  T.  18,  R.  6  W.,  from  which  point  the  ridge  leads  NNE. 
through  Alamo.  Its  general  height  is  about  30  feet  above  the  plain  west 
of  it,  and  still  more  above  the  bluff  of  Sugar  Creek  Valley  on  the  east. 
Near  Alamo,  in  sees.  23  and  26,  several  basins  occur,  the  deepest  of  which 
are  15  or  20  feet  below  their  bordering  rims.  The  basins  iisually  have 
outlets  through  narrow  breaks  in  the  rim.  West  of  the  main  belt  for 
several  miiles  the  surface  is  very  flat,  but  east  of  it  there  are  ridges  and 
knolls  extending  to  the  valley  of  Sugar  Creek.  The  knolls  are  nearly  as 
prominent  as  those  in  the  main  belt,  but  are  less  closely  aggregated.  They 
are  separated  by  nearly  plane  tracts.  The  northeast  fourth  of  Ripley 
Township,  comprising  a  tract  3  or  4  miles  wide,  is  sharply  tmdulatory,  with 
many  knolls  and  ridg-es  20  to  40  feet  high.  The  moraine  here  is  over- 
ridden by  a  late  Wisconsin  moraine.  The  latter  trends  NNW.-SSE., 
intersecting  the  Champaign  moraine  at  an  angle  of  about  45  degrees. 

The  Inner  Ridge  of  the  Champaign  morainic  system  is  well  defined 
from  its  point  of  separation  from  the  Middle  Ridge,  near  Philo,  Illinois, 
eastwai'd  to  the  Fairmount  geodetic  station.  It  is  about  one-half  mile  in 
width  and  20  feet  in  height,  and  presents  a  gently  undulating  surface. 
South  and  east  from  the  geodetic  station  there  is  a  series  of  knolls  and 


230  THE  ILLINOIS  GLACIAL  LOBE. 

short,  rather  sharp,  ridges.  The  most  promiueut  ridge  traverses  sees.  25, 
26,  and  36,  T.  18,  R.  13  W.,  and  its  highest  points  stand  fully  50  feet 
above  the  bordering  plain,  yet  its  width,  including  slopes,  is  scarcely  one- 
half  mile.  A  lower  ridge  passes  north-south  through  sees.  16  and  21.  In 
sees.  9  and  10  also  there  is  a  low  ridge  which  ti-ends  WNW.-ESE.,  and 
stands  perhaps  20  feet  above  the  bordering  plain.  Blue  Mound,  a  shai-p  knoll 
in  sec.  11,  stands  55  feet,  by  aneroid,  above  the  border  plain  and  covers 
about  30  acres.  In  sees.  10  and  15,  T.  18,  R.  12  "VV.,  a  well-defined  undu- 
latory  ridge  occurs  which  carries  shallow  basins  on  its  crest  and  slopes. 
There  are  several  knolls  10  or  15  feet  high  in  sees.  7  and  18  of  this  town- 
ship, which  should  probably  be  referred  to  this  moraiiiic  belt.  From  Blue 
Mound,  in  sec.  11,  T.  18,  R.  13  W.,  to  sec.  27,  T.  18,  R.  11  W.,  a  distance 
of  10  miles,  only  occasional  low  ridges  and  knolls  are  to  be  seen,  the 
highest  of  which  i-ise  scarcely  more  than  15  feet  above  the  bordering  plain. 
But  from  sec.  27  southeastward  to  the  Wabash  River  bluff  near  Eugene, 
Indiana,  a  distance  of  7  to  8  miles,  there  is  a  well-defined  ridge,  about  a 
half  mile  in  width,  whose  highest  points  rise  40  feet  or  more  above  the 
bordering  plain,  while  its  lower  points  seldom  fall  below  20  feet.  It  carries 
winding  ridges  and  sharp  knolls  on  its  surface,  among  which  shallow  basins 
are  inclosed. 

East  from  the  Wabash  River  this  moraine  has,  as  a  nile,  a  gentle 
swell-and-sag  topography,  with  undulations  of  10  feet  or  less  and  a  relief 
of  scarcely  20  feet.  In  the  vicinity  of  Rynear,  however,  in  sees.  2  and  3, 
T.  19,  R.  7  W.,  there  is  a  chain  of  knolls  standing  20  to  40  feet  higher  than 
the  plain  on  the  north,  and  occupying  a  belt  about  a  half  mile  in  width.  The 
Cleveland,  Cincinnati,  Chicago  and  St.  Louis  Railway  passes  over  a  spur 
from  this  ridge  just  east  of  Rynear,  while  west  of  the  village  it  passes  through 
a  gap  in  the  ridge.  In  sec.  9  the  ridge  takes  a  NE.  to  SW.  trend  and  is  dis- 
tinctly traceable  to  the  southwest  part  of  the  section.  The  remainder  of 
this  belt  consists  of  knolls  more  or  less  closely  aggregated  but  seldom 
exceeding  ?  0  feet  in  height. 

The  weak  l>elt  leading  northward  from  Veedersburg  to  Rob  Roy  has 
no  prominent  knolls  except  in  the  northern  portion.  The  slight  undula- 
tions which  it  presents,  however,  are  in  decided  contrast  to  the  very  flat 
surface  of  the  plain  on  the  west.  Although  the  moraine  has  but  feeble 
expression  its  relief  is  sufficient  to  cause  the  sontliwavd  deflection  of  Coal 


THE  CHAMPAIGN  MOEAINIC  SYSTEM.  231 

Creek.  The  slope  of  the  country  is  such  that  the  creek  would  have  con- 
tinued directly  westward  to  the  Wabash  and  reached  that  river  in  about  6 
miles  from  the  point  where  it  encounters  the  drift  ridge,  but  the  deflection 
occasioned  by  the  drift  ridge  makes  it  necessary  for  it  to  flow  not  less  than 
25  miles  before  reaching  the  Wabash.  At  the  northern  end  of  the  rido-e. 
near  Kob  Roy,  knolls  20  to  30  feet  high  occur,  and  points  in  sec.  25,  T. 
21,  R.  8  W.,  stand  50  or  60  feet  above  the  bordering  plain.  To  give  added 
morainic  expression  these  prominent  points  are  thickly  strewn  with  bowlders. 

THICKNESS    AND    STRUCTUEE    OF    THE   DRIFT. 

The  thickness  of  drift  in  this  morainic  system  is  to  be  measui-ed  by  the 
relief  of  its  ridges  rather  than  by  the  distance  to  rock,  for  beneath  the  level 
of  the  base  of  the  ridges  older  sheets  of  drift  occur.  The  relief,  as  shown 
above,  nowhere  reaches  100  feet  and  seldom  exceeds  50  feet.  The  distance 
to  rock,  on  the  other  hand,  rarely  falls  below  50  feet  along  the  line  of  the 
ridges,  and  in  places  is  known  to  be  300  feet.  In  the  Indiana  portion  and 
in  eastern  Illinois,  for  some  20  miles  west  of  the  State  line,  rock  is  usually 
entered  at  100  feet  or  less,  and  there  are  numerous  rock  exposures  along 
the  principal  streams.  Farther  west  the  rock  surface  lies  lower,  and  the 
few  borings  which  reach  the  rock  indicate  that  the  average  thickness  of  the 
drift  in  Champaign,  Piatt,  and  McLean  counties  is  not  less  than  200  feet, 
while  the  maximum  thickness  is  fully  300  feet. 

These  morainic  ridges  are  composed  in"  the  main  of  till.  Gravel  and 
sand  beds  are  occasionally  foimd  in  the  knolls  and  near  the  level  of  the 
base  of  the  ridges,  but  even  in  these  situations  they  are  of  comparatively 
limited  extent.  Along  this  morainic  system  in  Indiana  there  is  sufficient 
gravel  in  the  knolls  to  supply  material  for  improving  the  roads  in  their 
vicinity,  but  in  Illinois  road  material  is  generally  difficult  to  obtain. 
Grravelly  knolls  were  observed  east  of  Ridge  Farm  village  and  on  the 
inner  slope  of  the  moraine  near  Champaign  and  Urbana.  Along  the  shai-ply 
ridged  portion  of  the  inner  ridge  in  the  vicinity  of  the  State  line,  and  also 
in  the  sharp  knolls  near  Fairmount,  there  is  considerable  gravel  associated 
with  the  till.  It  is  possible  that  many  knolls  contain  gi-avel  wliich  has  not 
yet  been  discovered.  On  the  whole,  water-bearing  beds  are  more  extensive 
in  the  Indiana  portion  of  these  morainic  ridges  than  in  the  Illinois  portion. 
In  the  latter  district  wells  are  often  sunk  to  a  level  below  the  base  of  these 


232  THE  ILLINOIS  GLACIAL  LOBE. 

di'ift  ridges  before  water  can  be  obtained,  while  in  Indiana,  water-bearing 
beds  are  usually  found  before  reaching  the  base  of  the  ridges. 

This  morainic  system  is  characterized  by  a  limited  number  of  surface 
bowlders,  and  a  moderate  number  are  incorporated  with  the  till.  The 
majority  of  the  surface  l)owlders  are  crystalline  rocks  of  Canadian  deriva- 
tion. They  are  usually  subangular  and  seldom  show  striated  faces.  As  in 
the  di'ift  sheets  of  this  region  generally,  the  bowlders  incorporated  in  the 
till  appear  to  be  much  more  frequently  glaciated  than  those  on  the  surface. 
There  is  also  apparently  a  larger  proportion  of  limestone  rocks  of  local  or 
semilocal  derivation  embedded  in  the  till  than  are  found  on  the  surface.^ 

Several  large  blocks  of  limestone,  however,  were  found  on  the  surface 
in  Champaign  County,  Illinois.  At  George  Stewart's,  a  few  miles  southeast 
of  Philo,  on  a  prominent  portion  of  the  ridge  in  sec.  4,  T.  17,  R.  10  W.,  two 
large  limestone  blocks  were  examined  by  the  writei*.  They  are  of  gray 
color  and  contain  Pentamerus  shells,  apparently  of  Niagara  age.  Mr. 
Stewart  has  dug  to  a  depth  of  about  4  feet  at  the  side  of  one  of  the  rocks 
without  reaching  its  base,  and  it  has  a  surface  exposure  nearly  10  feet 
square.  The  other  block  has  been  uncovered  for  a  space  of  about  a  square 
rod  and  extends  some  distance  beneath  the  ground.  The  nearest  known 
outcrop  of  this  rock  formation  toward  the  north  (the  direction  from  which 
the  ice  came)  is  in  northern  Iroquois  County,  some  60  miles  distant. 

In  Indiana  the  district  traversed  by  these  moraines  and  the  morainic 
ridges  themselves  are  characterized  by  few  surface  bowlders,  excejDt  in  north- 
western Montgomery  and  northeastern  Fountain  counties.  They  there 
aliound  on  the  plains  as  Avell  as  on  the  ridges.  It  seems  probable,  however, 
that  these  bowlders  are  to  be  connected  with  the  late  Wisconsin  ice  invasion, 
though  their  position  is  such  as  to  throw  them  outside  a  regular  border  of 
the  ice  sheet.  The  bowlders  apparently  connect  on  the  north  with  well- 
defined  bowlder  belts  of  late  Wisconsin  age  which  lead  northward  from  the 
AVabash  River  near  Williamsport.  Whether  the  bowlders  on  the  group  of 
knolls  near  Rob  Roy  referred  to  above  were  deposited  by  this  later  invasion 
is  uncertain.  It  is  also  not  entirely  certain  that  these  knolls  are  independ- 
ent (if  the  later  invasion. 

The  surface  of  the  ridges  of  the  Champaign  morainic  system,  as  well 
as  the  plains  between  them,  is  commonly  covei'cd  with  a  pebbleless  clay 

I  For  (lisciiSBion  of  these  features  see  Cbamliorlin  :  ,Jour.  Geol.,  Vol.  1, 1803,  pp.  47-60. 


THE  CHAMPAIGN  MORAINIC  SYSTEM.  233 

loam  2  to  4  feet  in  thickness,  and  this  has  probably  concealed  many 
bowlders  which  would  otherwise  have  been  exposed  on  the  sm-face  of  the 
till.  The  number  of  bowlders  on  the  surface  is  less  than  on  the  plains 
between  this  morainic  system  and  the  Cerro  Gordo  moraine.  The  sheet  of 
loam  is  apparently  distinct  in  origin  from  the  sheet  of  till  which  underlies 
it,  but  no  evidence  was  discovered  that  it  was  separated  from  it  by  a  wide 
time  interval.  This  silt  is  distinct  from  the  main  loess  deposit  of  western 
and  southern  Illinois,  since  the  latter  preceded  the  Shelbysalle  moraine  in 
its  date  of  deposition.  The  origin  of  surface  silts  of  this  class,  like  that  of 
the  great  loess  deposits,  is  problematical. 

A  buried  soil  is  frequently  found  beneath  the  ridges  of  this  morainic 
system,  but  it  appears  to  be  at  a  lower  horizon  than  the  base  of  the  drift 
deposited  in  connection  with  these  moraines.  Its  horizon  is  probably  at 
the  junction  of  the  Shelby ville  drift  sheet  with  the  underlying  older  di-ift. 
Professor  Rolfe,  of  the  Illinois  State  University,  has  collected  records  of 
many  wells  in  southern  Champaign  County,  between  Urbana  and  Tolono, 
in  which  a  buried  soil  is  found  at  a  depth  of  60  to  100  feet.  These  records 
have  not  as  yet  been  published  by  him.  When  found  beneath  the  plains 
the  depth  to  the  soil  is  less  than  when  beneath  the  drift  ridges.  On  the 
ridge  in  the  vicinity  of  Tolono  it  is  struck  at  about  100  feet  and  it  is  found 
at  nearly  as  great  depth  on  the  ridge  near  Urbana,  while  on  intervening 
plains  the  depth  is  but  60  to  75  feet.  Instances  of  buried  muck  reported 
from  Vermilion  County,  Indiana,  by  F.  H.  Bradley^  occur  beneath  the 
gravel  of  the  Wabash  terraces.  Wells  were  sunk  through  about  60  feet  of 
alluvial  sand,  and  then  encountered  6  to  10  feet  of  soft,  sticky  bluish  mud 
filled  with  leaves,  twigs,  and  trunks  of  trees.  In  Fountain  County,  Indiana, 
between  the  main  morainic  belt  and  the  Inner  Ridge,  there  is  a  plain  in 
which  a  black  muck  has  been  struck  below  the  till  at  depths  of  25  to  50 
feet.  Although  the  depth  is  much  less  than  in  Champaign  County,  Illinois, 
the  soil  is  thought  to  be  at  the  same  horizon,  namely,  the  junction  of  the 
Shelbyville  drift  sheet  with  the  underlying  older  di-ift. 

The  detailed  discussion  of  well  sections  which  follows  beg-ins  at  the 
west  end  of  the  morainic  system  in  Piatt  County  and  passes  eastward,  and 
serves  to  illusti'ate  variations  in  the  structure  from  point  to  point.  There 
are,  ixnfortunately,  but  few  reliable  records  obtained. 

'  Geol.  of  Indiana,  1869,  p.  140. 


234  THE  ILLINOIS  GLACIAL  LOBE. 

A  well  oa  the  farm  of  Mrs.  Robert  Carson,  iu  eastern  Piatt  Couut"S', 
near  tlie  south  border  of  the  moraine,  reached  a  depth  of  200  feet  without 
encountering  rock.  It  appears  to  have  been  mainly  through  a  fine  sand. 
On  the  north  border  of  Blue  Ridge  Frank  Delaney  sunk  a  well  to  a  depth 
of  280  feet  without  encountering  I'ock.  A  well  was  sunk  by  George  Frank- 
enburgher  on  the  crest  of  the  moraine,  2  miles  east  of  Mahomet,  to  a  depth 
of  about  200  feet  without  encountering  rock.  It  was  almost  entu-ely 
through  till. 

An  experimental  boring  for  gas,  oil,  etc.,  made  at  the  city  of  Cham- 
paign in  the  winter  of  1891-92,  is  reported  by  E.  M.  Bvut,  of  Champaign, 
to  have  the  following  drift  section: 

Section  of  horimj  at  Champaign,  Illinois. 

Feet. 

Black  soil  and  a  pebbleless  clay  subsoil -. 4 

Yellow  and  gray  pebbly  clay 44 

Quicksand 12 

Gravel 7 

Gray  pebbly  clay 35 

Quicksand - 71 

Water-bearing  gravel 6 

Hanlpan  (exact  nature  not  noted) 5 

Quicksand 11 

Gravel 7 

Hard,  pebbly  clay 51 

Clay  containing  small  pieces  of  coal 1 

Quicksand  and  gravel 21 

Gray  clay  containing  pieces  of  coal  near  bottom 9 

Quicksand 16 

Total  drift 300 

The  following  section  of  an  attempted  coal  shaft  sunk  by  Jolin  Faulds 
at  Champaign  appears  in  the  Geology  of  Illinois  (Vol.  IV.,  p.  272): 

Section  of  coal  shaft  at  Ghamimign,  Illinois. 

Feet. 

Soil,  clay,  and  ([uicksaud 17 

Red  and  blue  clay 73 

Peat 2 

Quicksand,  with  tree  7  inches  in  diameter 9 

Soft  yellow  clay 9 

Sand 3 

Yellow  clay 7 

Sand  and  gravel 59 

Total  depth 179 

The  bottom  of  the  drift  was  not  reached  in  this  place.  The  statement 
is  made  that  nn  earlier  boring  near  l)y,  of  which  a  complete  record  was  not 


THE  CHAMPAIGN  MORAINIO  SYSTEM.  235 

accessible,  is  said  to  have  reached  a  bkie  shale  at  168  feet.     This  sup- 
posed shale  may,  however,  prove  to  be  hard  blue  till. 

A  boring  made  iu  Urbana  in  1884,  about  a  half  mile  east  of  the 
roundhouse  of  the  Cleveland,  Cincinnati,  Chicago  and  St.  Louis  Railway, 
has  the  following  section,  as  reported  by  Prof  C.  W.  Rolfe: 

Section  of  boring  at  Urbana,  Illinois. 

I'eet. 

Soil - 1 

Yellow  clay  containing  few  pebbles .- 12 

Blue  cla)-  containing  few  pebbles 13 

Very  stony  clay 32 

Coarse  sand  and  gravel I't 

Black  soil 2 

AVater-bearing  yellow  sand Ifi 

Blue  clay 1 

Quicksand ^i 

Blue  clay -  1 

Quicksand .- - 3 

Blue  bowlder  clay 16 

Quicksand - 35 

Blue  bowlder  clay li^ 

Sand  and  gravel - 17 

Quicksand 69 

Gravelly  sand 9 

Total  drift 265 

The  altitude  of  the  well  mouths,  both  in  the  Champaign  and  in  the 
Urbana  borings,  is  about  750  feet  above  tide.  Within  IJ  miles  east  of  the 
com-t-house  in  Urbana,  at  a  level  but  a  little  lower  than  the  well  just 
recorded,  rock  is  struck  within  100  feet  of  the  surface.  On  a  line  eastward 
from  that  point  to  the  Wabash  Valley,  in  Indiana,  the  drift  seldom  exceeds 
100  feet  in  thickness. 

A  well  at  Thomas  Goody's,  in  Philo,  on  the  crest  of  the  moraine, 
attained  a  depth  of  171   feet  without  reaching  rock,   and  penetrated  the 

following  drift  beds: 

Section  of  icell  at  Philo,  Illinois. 

Feet. 

Pebbly  clay  changing  from  brown  to  blue 20 

Pebbly  bhie  clay 75 

Pebbly  blue  clay,  interbedded  with  dry  sand  in  thin  beds 30-35 

Sandy  clay  called  hardpan 4 

Fine  yellow  sand,  water  bearing 36 

Total 171 

A  well  on  the  moraine  2  miles  south  of  Philo,  in  process  of  boring  at 
the  time  of  my  visit,  penetrated  110  feet  of  till,  mainly  of  blue  color,  and 


236  THE  ILLIN^OIS  GLACIAL  LOBE. 

.apparently  referable  to  the  Shelbyville  aud  later  sheets.  Beneath  tliis 
depth  alternating  beds  of  sand  and  clay  of  blue  color  continued  46  feet  to 
the  bottom  of  the  well.  Several  other  wells  have  l^eeu  made  along  the 
moraine  in  this  count}*  whose  depths  exceed  100  feet.  As  a  rule  they  pass 
through  a  thick  bed  of  till  before  striking  water-bearing  sand  or  gTavel.  A 
similar  sheet  of  till  is  passed  through  on  the  plain  between  the  middle  and 
oiiter  ridges  in  southern  Champaign  County  and  on  the  inner  ridge  and 
bordenng  plains  in  eastern  Champaign  County.  A  boring  at  Sidney  on  a 
plain  north  of  the  inner  ridge,  made  in  1884  by  the  Sidney  Mineral 
Company,  penetrated  biit  9o  feet  of  drift,  as  follows:^ 

Section  of  drift  in  a  boring  at  Sidney,  Illinois. 

Feet. 

Yellow  clay,  containing  few  pebbles 17 

Blue  clay,  containing  few  pebbles 18 

Pebbly  blue  clay 5 

Pebbly  yellow  clay 15 

Sand  and  gravel 5 

Peljbly  cbiy 35 

Tntal  drift 95 

In  northeast  Douglas  Count}*,  aud  thence  eastward  along  tlie  moraine, 
wells  are  usually  but  30  to  40  feet  in  depth  and  very  rarely  reach  a  depth 
of  100  feet.  They  are  mainly  through  till,  except  in  southeastern  Vermilion 
County,  where  in  some  cases  considerable  gravel  is  penetrated. 

A  well  on  the  north  face  of  the  Inner  Ridge,  a  short  distance  east  of 
the  State  line,  at  the  residence  of  Mr.  Malone,  did  not  reach  the  bottom  of 
the  drift  at  a  depth  of  241  feet,  and  failed  to  obtain  water.  The  well 
mouth  has  an  altitude  about  625  feet  above  tide,  or  160  feet  above  the 
Wabash  River.     The  following  section  was  furnished  by  Jlr.  Malone : 

Section  of  Malone' s  icell  near  Eugene,  Indiana. 

Feet. 

Pebbly  yellow  clay 15 

Pebbly  blue  clay 35 

Dry  sand  and  gravel 10 

Hard  pebbly  gray  clay  (probably  lllinoian) 55 

Alternations  of  clay  with  sand  aud  gravel  in  thin  beds 125 

Total  depth 240 

F.  H.  Bradley  has  published  the  following  section  of  drift  exposed  on 
a  branch  of  Johnson's  Creek,  near  Newport,  Indiana:" 

•  For  this  section  I  am  indebted  to  Prof.  C.  W.  Rolfe. 
■^Geoloiiy  of  Indiana,  1869,  p.  141. 


THE  CHAMPAIGN  MOEAIJSIIO  SYSTEM.  237 

Section  of  drift  near  Neioport,  Indiana. 

Feet.  In. 

Bowlder  clay,  with  pebbles  of  Silurian  limestone  autl  trap 30        0 

Yellow  clay,  with  fragments  of  coal,  shale,  sandstone,  etc 0        4 

Bowlder  clay,  with  pebbles  of  Silurian  limestone    25        0 

Ferruginous  sand Streak. 

Bowlder  clay,  from  the  northwest,  with  pebbles  of  various  metamorphic  rocks  and  trap,  and 
nuggets  of  native  copper 50        0 


Total  exposure. 


105        4 


East  of  the  Wabash,  in  Parke  Coiinty,  wells  along  the  outer  or  main 
belt  and  on  the  plain  north  of  it  are  seldom  more  than  30  feet  in  depth. 
They  pass  through  about  15  feet  of  yellow  till,  beneath  which  some  of  them 
enter  blue  till,  while  others  enter  gravel.  Thin  beds  of  sand  or  gravel  are 
often  found  associated  with  the  yellow  as  well  as  the  blue  till. 

Wells  in  western  Montgomery  County  are  in  some  cases  sunk  to  a 
depth  of  50  or  75  feet,  mainly  through  blue  till.  On  the  plain  in  Fountain 
County,  and  also  on  the  inner  morainic  ridge,  wells  seldom  reach  a  depth 
of  50  feet,  and  usually  obtain  water  without  entering  rock,  there  being  beds 
of  water-bearing  sand  or  gravel  associated  with  the  till  sheet. 


CHAKACTBR   OF    OUTWASH. 


As  a  rule  the  plains  outside  the  ridges  of  this  morainic  system  show 
scarcely  any  sand  or  gravel  outwash  from  the  moraine,  and  there  appears 
to  have  been  only  a  gentle  movement  of  waters  from  the  ice  margin  south- 
ward down  the  valleys. 

At  the  point  where  the  Sangamon  River  emerges  from  the  moraine  in 
the  village  of  Mahomet  there  is  a  gravelly  outwash  having  a  depth  of  6  or  7 
feet,  which  caps  the  till  plain  on  the  immediate  border  of  the  valley.  Expo- 
sures are  to  be  seen  east  of  the  railway  station  and  also  at  several  points  in 
the  village.  The  exposures  east  of  the  railway  station  show  a  bed  of  loess- 
like silt  about  3  feet  in  thickness  immediately  below  the  gravel,  and  beneath 
this  a  brownish-yellow  till.  The  loess-like  silt  is  similar  to  that  which 
covers  the  plains  quite  extensively  in  this  region.  The  gravel  overwash  is 
of  very  limited  extent,  reaching  out  scarcely  a  half  mile  from  the  south 
border  of  the  moraine.  It  merges  into  low  gravelly  knolls  on  the  border 
of  the  moraine.  These  features  seem  to  leave  no  question  of  the  gravel 
being  derived  from  the  ice  sheet  during  the  formation  of  the  moraine. 
Attention  has  already  been  called  to  a  gravelh^  tract  along  the  Sangamon 


238  THE  ILLINOIS  GLACIAL  LOBE. 

River  below  this  point.  The  small  amount  of  outwash  shown  at  the  border 
of  the  moraine  seems  to  make  it  doubtful  if  the  gravel  belt  along  the  river 
was  chiefly  formed  as  morainic  outwash.  The  gravel  may  be  largely  a 
residue  from  the  cutting  down  of  the  sheet  of  drift  outside  the  moraine. 

Kaskaskia  and  Embarras  valleys  have,  as  a  laile,  either  silt  or  till 
banks  where  they  border  the  ridges  of  this  morainic  system.  It  is  probable 
that  the  ice  sheet  had  feeble  outwash  at  these  valleys,  as  they  are  favorably 
situated  for  receiving  any  outwash  which  may  have  been  contributed  from 
the  moraine,  the  course  of  the  Kaskaskia  being  for  several  miles  but  a  short 
distance  outside  the  Outer  Ridge  and  the  com-se  of  the  Embarras  being  for 
an  even  greater  distance  just  outside  the  Middle  Ridge. 

Near  the  head  of  Bruillett's  Creek,  in  northern  Edgar  County,  the  plain 
outside  the  moraine  has  an  area  of  several  square  miles  which  is  underlain 
by  gravel.  Tributaries  of  Bruillett's  Creek  lead  down  from  the  moraine  into 
this  plain  and  lose  their  waters  in  its  gravel.  In  some  cases  these  streams 
do  not  maintain  a  channel  in  this  plain.  It  is  not  entirely  certain  that 
this  ffravel  is  an  outwash  from  the  moraine,  since  the  moraine  itself  is  of  a 
stiff  clayey  constitution  on  the  immediate  borders  of  the  gravelly  plain.  If 
the  moraine  had  a  gravelly  constitution  on  this  border,  as  it  does  at  Mahomet, 
tlie  case  would  seem  more  certain.' 

Along  the  Wabash  River  Valley  extensive  gravel  teiTaces  occur  both 
above  and  below  the  points  where  the  ridges  of  this  morainic  system  cross. 
Possibly  a  portion  of  the  gi-avel  connects  with  this  morainic  system,  but  by 
far  the  larger  part  connects  with  moraines  of  later  date  which  cross  farther 
up  the  valley. 

Near  Bloomingdale,  Indiana,  a  gravel-filled  valley  not  now  occupied  by 
a  stream  leads  southward  from  the  moraine  across  Leatherwood  Creek  to 
the  valley  of  Rocky  Run,  a  distance  of  2  miles,  and  thence  continues  down 
Rocky  Run  to  the  Wabash  Valley.  The  portion  not  occupied  by  a  stream 
is  bordered  by  bluffs  30  to  50  feet  in  height,  and  has  a  width  of  from  one- 
third  to  one-half  mile.  The  relation  of  this  valley  to  the  Champaign 
morainic  system  is  not  definitely  settled.  It  is  perhaps  an  interglacial  val- 
ley, whose  upper  course  has  been  oveiridden  and  concealed  by  the  Cham- 
])aign  drift  sheet.  The  gravel  filling  in  its  bottom  may  prove  to  be  an 
outwash  from  the  moraine,  though  this  is  not  entirely  certain.  It  is  not 
evident  why  Leatlierwood  Creek  chose  a  passage  westward  instead  of  turn- 


THE  CHAMPAIGN  MORAIIsriO  SYSTEM.  239 

ing-  down  this  valley.  Its  flood  plain  is  now  only  about  20  feet  below  the 
level  of  the  bottom  of  the  abandoned  valley  at  the  point  where  it  crosses 
it,  and  the  difficulties  of  opening  a  westward  passage  seem  greater  than 
would  be  necessary  to  have  adopted  the  course  of  the  abandoned  valley. 

On  the  outer  border  of  the  Inner  Ridge  in  Shawnee  Township,  Fountain 
County,  Indiana,  just  north  of  the  point  where  Coal  Creek  is  deflected 
southward  by  the  morainic  ridge,  there  is  a  small  plain  underlain  with  gravel 
which  is  perhaps  an  overwash  from  the  moraine.  There  is  also  considerable 
gravel  along  Coal  Creek  below  the  bend,  preserved  in  terrace-like  remnants 
standing  35  to  50  feet  above  the  present  stream.  It  is  not  determined, 
however,  whether  this  gravel  is  an  outwash  from  the  drift  ridge  or  is  merely 
a  residue  formed  in  the  cutting  of  the  valley.  Against  the  latter  view  it 
may  be  said  that  the  present  stream  seems  scarcely  adequate  to  transport 
gravel  deposits  of  such  coarseness  as  are  here  displayed. 

Sugar  Creek  Valley  carries  gravel  terraces  in  its  lower  course,  but 
these  terraces  are  as 'well  developed  in  portions  of  the  valley  above  the 
crossing  of  this  morainic  system  as  below  that  point.  The  lower  course  of 
the  creek  is  on  the  inner  border  of  the  Outer  Ridge  of  this  morainic  system, 
and  thus  is  very  unfavorably  situated  for  receiving  an  outwash.  Further- 
more, the  gravel  terraces  seem  to  be  built  up  in  a  valley  which  had  been 
excavated  in  the  Champaign  drift  sheet.  It  is  hig-hly  probable,  therefore, 
that  these  gravel  terraces  have  no  connection  with  the  Champaign  morainic 
system,  but  are  of  later  date. 

ASSOCIATED    TILL    PLAINS. 

Between  the  ridges  of  this  morainic  system  there  are,  as  alread}^  noted, 
till  plains  ranging  in  width  from  1  or  2  up  to  about  10  miles  in  the  Illinois 
portion,  and  reaching  a  width  of  nearly  20  miles  in  Parke  and  Fountain 
counties,  Indiana.  On  these  plains  there  are  occasional  low  knolls,  but 
the  general  surface  is  much  smoother  than  that  of  the  bordering  morainic 
ridges. 

Another  plain  having  greater  extent  occupies  the  interval  between  the 
Inner  Ridge  of  the  Chamj)aign  morainic  system  and  the  Outer  Ridge  of 
the  Bloomingtou  morainic  system.  Its  width  at  the  northwest,  near  the 
corners  of  Ford,  McLean,  and  Champaign  counties,  is  about  15  miles,  and 
this  width  is  maintained  across  Champaign  County.     In  VeiTuilion  County, 


240  THE  ILLINOIS  GLACIAL  LOBE. 


Illinois,  it  decreases  to  10  or  12  miles,  and  continues  into  Indiana  with 
about  the  same  width.  On  this  plain,  as  on  the  plains  between  the  ridges 
of  the  Champaign  morainic  system,  the  surface  is  generally  much  smoother 
than  on  the  ridges.  There  are  occasional  knolls,  however,  which  reach  a 
height  of  30  feet  or  more,  and  swells  5  to  10  feet  in  height  are  found  in 
nearly  every  township. 

The  thickness  of  di'ift  differs  from  that  in  the  morainic  ridges  only  by 
the  measure  of  the  relief  of  the  ridges.  In  the  Indiana  portion,  and  for 
some  distance  westward  into  Illinois,  rock  is  often  encountered  at  a  depth 
of  50  feet  or  less,  but  in  Champaign  County  the  drift  tliickness  increases  to 
200  feet  or  more,  for  the  thickness,  as  on  the  ridges,  is  much  greater  in  the 
western  than  in  the  eastern  portion  of  the  county.  The  thick  drift  continues 
northwestward  into  Ford  and  McLean  counties. 

There  is  beneath  these  plains  a  buried  soil  found  at  a  depth  of  75  to 
100  feet  or  less  in  Champaign  County,  and  at  25  to  60  feet  in  counties 
farther  east.  This  appears  to  be  at  the  base  of  the  Shelby^'ille  drift  sheet. 
As  yet  no  soil  has  been  discovered  between  the  Champaign  and  Shelbj^ville 
sheets.  The  drift  appears  to  be  composed  more  largely  of  till  beneath 
these  plains  than  in  the  moraines,  but  sufficient  gravel  and  sand  occur  to 
afford  water  for  wells  throughout  most  of  the  region. 

SECTION  III.    BLOOMKVGTON^  MORAIIS^C   SYSTEM. 

The  system  of  moraines  to  which  the  name  Bloomington  is  applied  is 
scarcely  surpassed  in  strength  of  development  or  in  complexity  of  features 
by  any  other  morainic  system  in  the  early  Wisconsin  series.  It  is  one  of 
the  most  important  in  the  series,  not  only  because  of  its  strength  of  develop- 
ment but  because  it  extends  in  places  beyond  the  earlier  moraines  of  the 
series,  and  for  a  distance  of  about  120  miles  constitutes  the  border  of  the 
Wisconsin  drift.  It  receives  its  name  from  the  city  of  Bloomington,  Illinois, 
which  stands  on  a  prominent  portion  of  its  chief  ridge.  The  name  seems 
especially  pertinent  since  Bloomington  is  situated  near  the  middle  point  of 
this  morainic  loop,  just  as  Shelbyville  is  situated  near  the  middle  point  of 
the  Shelbyville  loop. 

Where  best  developed  there  are  two  bulky  ridges,  constituting  the 
outer  part  of  the  system,  and  two  smaller  ridges  constituting  the  inner  part. 
The  four  ridges  are  not  continuously  developed,  however,  since  the}-  inter- 


THE  BLOOMINGTON  MORAINIC  SYSTEM.  241 

lock  in  places,  and  the  weaker  ridges  fade  out  at  intervals.  In  places  each 
of  the  bulky  ridges  are  double  crested  and  more  or  less  distinctly  separable, 
making  four  ridges  aside  from  the  two  weaker  ones.  The  system  may  be 
traced  satisfactorily  for  a  distance  of  aboiit  300  miles  from  the  northern 
tier  of  counties  in  Illinois  around  to  the  western  tier  m  Indiana.  In  northern 
Illinois  this  system  becomes  so  closely  associated  with  other  systems  in  a 
composite  belt  that  further  tracing  seems  impracticable.  This  northern 
portion  from  Peoria  County  northward  overrides  or  becomes  united  with 
the  Shelbyville  morainic  system,  so  that  the  latter  is  no  longer  traceable. 
In  western  Indiana  the  Bloomington  system  is  overridden  by  moraines  of 
late  Wisconsin  date,  which  have  partially  concealed  its  further  course. 

DISTRIBUTION. 

The  Bloomington  morainic  system  (carrying  with  it  perhaps  the  Shel- 
byAalle  system)  separates  from  the  composite  belt  of  moraines  in  northern 
Kane  County  and  passes  in  a  course  slightly  south  of  west  across  central 
Dekalb  County,  occupying  a  space  about  12  or  14  miles  in  width.  Its 
outer  and  inner  borders  are  each  characterized  by  a  definite  ridge.  On  the 
borders  of  Dekalb  and  Lee  counties,  in  the  vicinity  of  Shabbona  and  Paw- 
paw, it  becomes  narrowed  to  only  6  miles,  owing  to  a  reentrant  angle  on 
the  outer  border.  Thus  far  the  weak  inner  members  of  the  system  are 
undeveloped.  Continuing  southwestward  it  expands  in  northern  Bureau 
County  to  a  width  of  18  or  20  miles.  This  does  not  include  a  weak  inner 
member  of  the  system  which  sets  in  near  Earlville  and  leads  southward 
along  a  line  several  miles  east  of  the  inner  border  of  the  main  ridges,  and 
whose  course  is  discussed  below.  The  ridge  along  the  inner  border  dies 
out  in  eastern  Bureau  County,  so  that  upon  approaching  the  Illinois  River 
in  southern  Bureau  County  only  the  ridge  on  the  outer  border  of  the  sys- 
tem is  maintained  in  strength.  The  ridge  which  dies  out  in  eastern  Bureau 
Count}^  a^jparently  finds  continuation  in  a  ridge  that  crosses  northern  McLean 
County,  as  noted  below.  The  bulky  ridge  passes  southward  through  west- 
em  Marshall  and  northeastern  Peoria  counties  and  occupies  a  width  of 
several  miles.  The  portion  in  northeastern  Peoria  County  is  well  shown  in 
the  Dunlap  topographic  sheet,  where  it  forms  the  divide  between  Kickapoo 
Creek  and  smaller  tributaries  of  the  Illinois  that  flow  eastward  into  the 
river.     The  Shelbyville  moraine  emerg-es  from  beneath  it  in  eastern  Stark 

MON  XXXVIII 16 


242  THE  ILLINOIS  GLACIAL  LOBE. 

County,  as  previously  noted.  This  feature  also  may  be  seen  on  the  Dun- 
lap  sheet,  the  point  of  emergence  being  near  Lawn  Ridge.  The  Blooming-- 
ton  ridge  crosses  the  Illinois  River  just  above  the  city  of  Peoria  and  passes 
southeastward  across  northern  Tazewell  County  with  an  elevated  semi- 
morainic  tract  on  its  eastern  border,  extending  into  western  Woodford 
County.  In  northwestern  McLean  County,  immediately  east  of  the  Macki- 
naw River,  two  prominent  ridges  are  found  in  place  of  the  one  ridg'e  farther 
west.  They  are  closely  associated  and  lead  across  the  county  in  a  cur^dng 
course  bearing  south  of  east  in  the  western  portion  and  north  of  east  in 
the  eastern  portion.  The  ridges  are  more  closely  associated  in  tlie  eastern 
than  in  the  western  portion  of  the  county,  but  nowhere  occupy  a  belt  more 
than  10  miles  in  width.  In  the  eastern  portion  the  width  is  not  more  than 
6  miles.  The  plane  tract  between  them  is  only  1  or  2  miles  in  width.  In 
Ford  County  a  slight  reentrant  angle  is  formed  immediately  north  of  Gib- 
son, and  the  morainic  system  which  bears  northeastward  in  the  western 
part  of  the  county  changes  abruptly  to  a  southeastward  course  in  the  cen- 
ti-al  portion.  The  inner  border  of  the  reentrant  portion  extends  northward 
as  far  as  Chatsworth  and  Piper.  From  this  reentrant  angle  the  outer  border 
leads  from  Gibson  southeastward  across  northeastern  Champaign  County, 
passing  near  Rantoul  and  Gifford,  and  enters  Vermilion  County  abr)ut  3 
miles  northwest  of  Fithian.  It's  course  is  thence  directly  eastward  across 
the  countj^  into  Indiana,  passing  a  couple  of  miles  nortli  of  Dan^nlle,  Illinois. 
It  is  very  clearly  defined  on  the  DauAalle  topographic  sheet.  In  Warren 
County,  Indiana,  its  course  changes  to  north  of  east,  following  nearly  the 
north  bluff  of  AVabash  River  to  Pine  Creek  Valley,  near  Williamsport.  The 
moi'aine  here  swings  northward  and  is  traceable  as  far  as  eastern  Benton 
County,  where  it  dies  away  in  a  gently  undulating  plain.  This  system  is 
overridden  by  a  series  of  weak  bowldery  moraines  of  the  late  Wisconsin 
series  in  northern  Warren  and  southern  Benton  counties,  but  is  not  greatly 
obscured  along  the  line  of  the  outer  belts.  Greater  obliteration  apparently 
occuiTed  a  few  miles  back  from  the  late  Wisconsin  border.  However,  the 
Bloomington  system  apparently  iinds  its  continuation  in  a  belt  of  very  thick 
drift  which  leads  from  Benton  County,  Indiana,  southeastward  across  Tip- 
pecanoe, Clinton,  Boone,  and  Hamilton  counties,  and  thence  eastwai-d  into 
Ohio.  But  tliis  belt  is  outside  tlie  territory  embraced  in  the  present  report. 
Returning  to  the  reentrant  angle  in  Ford  County,  Illinois,  the  inner 
border  of  the  Bloomington  system  is  found  to  i)ass  southward  from  I'iper, 


THE  BLOOMINGTOF  MOEAINIO  SYSTEM.  243 

near  Thawville  and  Loda,  and  thence  to  swing  eastward  in  a  curving 
course  through  eastern  Ford,  northern  Vermilion,  and  southeastern  IroqiTois 
counties.  The  inner  bulky  ridge  of  the  system  continues  eastward  to 
Fowler,  Indiana,  where  it  terminates  very  abruptly  a  few  miles  west  of  the 
outer  ridge. 

From  the  reentrant  ang-le  in  Ford  County  two  weak  ridges  are  trace- 
able westward.  The  inner  or  Cha,tsworth-Cayuga  Ridge  leads  from  Chats- 
worth  north  of  west  to  Cayuga,  where  for  a  few  miles  it  passes  beneath,  or 
is  nearly -obscured  by,  the  Marseilles  moraine.  Near  Blackstone,  in  north- 
ern Livingston  County,  a  ridge  which  is  probably  its  continuation  emerges 
from  beneath  that  moraine  and  passes  northwestward  nearly  parallel  with 
the  Vermilion  River  through  or  near  Kernan,  Grand  Ridge,  and  Farm 
Ridge  villages  to  the  Illinois  Valley  at  Utica.  For  a  part  of  the  course  it 
forms  the  divide  between  •the  Illinois  and  Vermilion  rivers  and  may  easily 
be  traced  on  the  Ottawa  and  Lasalle  topographic  sheets.  This  northern 
part  is  known  as  Grand  or  Farm  Ridge.  North  from  the  Illinois  its  course 
is  slightly  east  of  north  from  Utica  past  Eariville,  where  it  fades  out  near 
the  inner  margin  of  the  main  moraine  in  southern  Dekalb  County.  It  is 
well  shown  in  the  east  part  of  the  Lasalle  sheet  and  northwest  part  of  the 
Ottawa  sheet.  The  gaps  in  this  ridge  are  narrow,  and  are  discussed  below 
(p.  259).  This  ridge  probably  finds  its  correlative  east  of  the  Ford  County 
reentrant  angle  in  a  belt  of  undulating  or  slightly  ridged  drift  leading  east- 
ward across  central  Iroquois  County.  The  latter  belt,  however,  scarcely 
constitutes  a  definite  moraine,  being  distinctly  ridged  only  for  a  few  miles 
along  the  north  border  of  Sugar  Creek  east  from  Milford.  It  disappears 
beneath  a  moraine  of  late  Wisconsin  age  near  the  State  line  south  of 
Sheldon,  Illinois. 

The  other  ridge  which  leads  west  from  the  Ford  County  reentrant 
angle,  commonly  known  as  Cropsey  Ridge,  from  a  villag-e  situated  on  it,  is 
distinctly  traceable  across  the  northern  part  of  McLean  County,  where  it 
constitutes  the  water  parting  between  Mackinaw  and  Vei'milion  rivers.  It 
fades  out  in  the  vicinity  of  Gridley,  and  is  not  definitely  developed  toward 
the  west  or  north  until  the  Illinois  Valley  is  passed.  It  seems,  however,  to 
be  a  continuation  of  the  belt  which  fades  out  in  eastern  Bureau  County,  as 
noted  above.  The  character  of  the  topography  in  the  interval  between 
these  ridges  is  discussed  below  (p.  281). 


244  THE  ILLINOIS  GLACIAL  LOBE. 


RELIEF. 


The  relief  on  the  outer  border  seldom  falls  below  50  feet  and  in  places 
approaches  200  feet.  The  average  relief  is  probably  75  or  100  feet.  The 
least  relief  is  found  in  j)ortions  of  Ford  and  Champaign  counties,  Illinois, 
where  it  is  about  50  feet.  The  greatest  relief  is  found  in  southern  Lee  and 
northern  Bureau  counties,  where  the  moraine  is  bordered  on  the  west  by 
the  Grreen  Eiver  Basin.  The  moraine  here  has  an  altitude  of  900  to  1,000 
feet  or  more  above  tide,  while  the  basin  on  the  immediate  borders  of  the 
naoraine  rises  from  scarcely  700  feet  at  the  west  to  about  850  feet  at  the 
east,  thus  giving  the  moraine  a  relief  of  150  to  200  feet. 

Between  the  ridges  of  this  system  there  is  very  little  depression  in 
Dekalb  and  Lee  counties.  But  on  the  inner  border  of  the  system  in  these 
counties  there  is  nearly  as  pronounced  relief  .as  on  the  outer  border. 
Indeed,  in  places  it  exceeds  that  on  the  outer  border,  and  probably  it 
averag-es  100  feet.  The  relief  on  the  inner  border  continues  jDrominent 
southwestward  into  Bureau  County,  but  falls  off  rapidly  in  that  county, 
becoming  scarcely  perceptible  in  the  vicinity  of  the  Illinois  River.  The 
outer  ridge,  however,  maintains  its  great  relief  throughout  Bureau  County 
and  rises  100  feet  or  more  above  the  plain  and  lower  ridge  on  its  inner 
border  in  the  eastern  part  of  the  county.  In  southern  Bureau,  western 
Marshall,  and  northeastern  Peoria  counties  it  stands  150  feet  or  more  above 
the  narrow  upland  between  it  and  the  Illinois  Valley.  This  prominent 
ridge  probably  includes  both  the  Shelbyville  and  Bloomington  systems,  for 
the  former  separates  from  it  in  eastern  Stark  county,  as  noted  above.  Upon 
crossing  the  Illinois  into  Woodford  County  the  uplands  on  the  inner  border 
of  the  Bloomington  moraine  are  found  to  stand  but  a  few  feet  lower  than 
the  crest,  and  eastward  from  this  county  there  is  generally  a  very  gradual 
descent  on  the  inner  border  of  the  main  ridges,  a  descent  seldom  exceeding 
25  or  30  feet  to  the  mile. 

The  small  ridge  which  leads  across  northern  McLean  County  has  a 
relief  of  but  30  to  50  feet  on  its  outer  border  and  a  gradual  descent  on  its 
inner  border.  The  ridge  leading  northwestward  from  Chatsworth  to  Earl- 
ville  usually  rises  30  to  50  feet  above  the  outer  border,  but  reaches  about 
75  feet  in  places  in  central  Lasalle  County.  The  relief  on  the  inner  bor- 
der is  nearly  as  great  as  on  the  outer,  but  is  usually  more  gradual 


THE  BLOOMINGTOIf  MORAHSTIO  SYSTEM. 


245 


KANGE    IN    ALTITUDE. 


This  morainic  system  presents  a  range  in  altitude  of  only  about  300  feet, 
its  highest  points  being  slightly  more  than  1,000  feet  above  tide,  while  few 
points,  aside  from  valleys,  fall  below  700  feet.  The  range,  both  along  the 
crest  and  along  the  immediate  outer  border,  is  set  forth  by  counties  in  the 
followingr  table: 


Table  slioicing  range  in  altitude  of  the  Bloomington  morainic  system. 


County. 


Dekalb  (Illinois)  . ... 

Ogle  (Illinois) 

Lee  (Illinois) 

Bureau  (Illinois) 

Marshall  (Illinois) . . . 

Peoria  (Illinois) 

Tazewell  (Illinois)..-. 

McLean  (Illinois) 

Ford  (Illinois) 

Champaign  (Illinois) 
Vermilion  (Illinois)  . 
Warren  (Indiana)  ... 
Benton  (Indiana) 


Crest,  above 
tide. 


Feet. 
875-     975 
875-     940 
900-1, 025 
700-    989 


800- 
700- 
700- 
775- 
775- 
750- 
680- 
700- 
750- 


900 
830 
825 
913 
860 
830 
790 
775 
825 


Outer  border, 
above  tide. 


Feet. 
775-850 
790-820 
740-860 
675-825 
700-800 
650-775 
650-725 
700-820 
740-760 
700-760 
630-700 
625-675 
675-725 


SURFACE    CONTOUES. 


A  general  statement  can  scarcely  be  made  which  will  set  forth  the  vari- 
ations in  contour  or  topographic  expression  of  this  morainic  system  through- 
out its  entire  leng-th.  It  is  found  convenient  to  discuss  it  in  sections, 
beginning  at  the  north  and  proceeding  southward.  The  first  section 
embraces  the  portion  between  western  Kane  County,  where  this  system 
separates  from  the  morainic  complex  of  northern  Illinois,  and  the  head  ot 
Bureau  Creek  in  northeastern  Lee  County,  a  section  35  or  40  miles  in 
length.  The  second  section  (about  50  miles)  embraces  the  portion  drained 
by  Bureau  Creek  and  its  tributaries.  The  third  section  (40  miles)  embraces 
the  portion  along  the  west  side  of  the  Illinois  in  Bureau,  Marshall,  and 
Peoria   counties.       The    fourth    section    (20  miles)  embraces  the  portion 


246  THE  ILLINOIS  GLACIAL  LOBE. 

between  the  Illinois  and  ]\Iackinaw  rivers  in  Tazewell  and  Woodford  coun- 
ties. The  fifth  section  (50  to  55  miles)  embraces  the  portion  between  the 
Mackinaw  River  and  the  reentrant  angle  in  Ford  Connty.  The  sixth  sec- 
tion (nearlv  100  miles)  embraces  the  portion  between  the  reentrant  ang-le 
in  Ford  CouutA*,  Illinois,  and  points  where  this  system  passes  beneath  the 
moraines  of  late  Wisconsin  age  in  Benton  and  Warren  counties,  Indiana. 
For  the  distribution  of  the  several  sections  see  PL  VI. 

Between  western  Kane  County  and  the  head  of  Bureau  Creek. Tlie     SeCtloU     betWeCU    WeSt- 

ern  Kane  County,  Illinois,  and  the  head  of  Bureau  Creek,  taken  as  a  whole, 
consists  of  a  mass  of  di-ift  standing  50  to  100  feet  or  more  above  the  plains 
on  the  northwest  and  southeast  borders,  and  occupying  a  width  of  6  to  15 
miles.  Much  of  the  surface  is  nearly  plane,  and  differs  but  little  from  that 
of  the  plain  on  the  southeast.  ■  There  is,  however,  scarcely  a  square  mile  in 
which  knolls  10  to  20  feet  high  are  not  present,  and  also  shallow  basins 
which  contain  ponds.  The  decidedly  morainic  expression  is  confined  to 
three  somewhat  naiTOw  belts,  one  on  the  outer  border,  another  on  the  inner 
border,  and  an  intermediate  less  definite  belt 

The  belt  on  the  outer  border  leads  fi'om  Hampshire  westward  into 
Dekalb  County,  crossing  South  Kishwaukee  River  just  above  the  bend  near 
Genoa,  and  then  curves  around  to  the  southwest  and  south  in  western  De- 
kalb and  southeastern  Ogle  and  eastern  Lee  counties.  Its  width  is  seldom 
more  than  3  miles,  and  in  places  scarcely  reaches  2  miles.  From  Hamp- 
shire Avest  to  the  Kishwaukee  River  it  is  less  prominently  ridged  tlian  west 
of  that  stream,  there  being  a  rise  of  scai-cely  50  feet  to  its  highest  points 
from  the  plain  on  the  north.  This  ^jortion,  however,  has  about  as  much 
morainic  expression  as  the  higher  part  of  the  border  to  the  west.  Knolls 
10  to  25  feet  are  closely  aggregated  and  inclose  shallow  basins.  The  basins 
are  usually  depressed  but  5  or  6  feet  below  the  lowest  part  of  their  rims,  and 
occupy  only  an  acre  or  two.  Occasionally  a  basin  occupying  as  much  as  10 
acres  is  to  be  seen.  From  South  Kishwaukee  River  south \\'estward  through 
western  Dekalb  and  southeastern  Ogle  counties,  the  outer  belt  consists  of  a 
series  of  narrow  ridges  with  shallow  sags  between  them,  each  trending  with 
the  entire  belt  in  a  NE.-SW.  course,  changing  to  southward  in  Ogle  County. 
The  ridires  are  each  a  mile  or  less  in  width  and  stand  30  to  50  feet  above 
the  intervening  sags.  There  are  in  places  four  ridges,  but  usually  only  two 
or  three.     Each  ridge  has  gentle  undulations  on  its  crest  and  slope,  seldom 


THE  BLOOMINGTOl^r  MORAHsTIC  SYSTEM.  247 

more  than  10  or  15  feet  high.  This  breaking  up  of  a  morainic  belt  into 
several  ridges  at  a  salient  curve  is  a  common  featm-e  in  this  and  other 
morainic  systems.  In  Ogle  and  northeastern  Lee  counties  sloughs  are  a 
conspicuous  feature  among  the  knolls.  This  outer  belt  is  interrupted  by 
several  gaps,  occupied  by  streams,  which  head  on  its  inner  border  and  pass 
through  it  to  the  lower  outlying  districts.  Named  in  order  from  east  to  west 
there  are  the  following:  Coon  Creek,  South  Kishwaukee  River,  Owen's 
Creek,  Killbuck  Creek,  Kite  River,  and  two  branches  of  Willow  Creek. 
The  crest  of  the  morainic  belt  is  absent  for  a  mile  or  more  at  each  of  these 
valleys.  Apparently  there  were  gaps  of  this  width  in  it  prior  to  the  open- 
ing of  the  drainage  lines,  for  the  slopes  bordering  the  valleys  carry  knolls 
and  shallow  basins  such  as  characterize  slightly  eroded  portions  of  the  belt. 
As  shown  below,  these  gaps  were  probably  formed  by  streams  issuing  from 
the  ice  sheet.  The  valley  bottoms  range  in  width  from  60  rods  up  to  fully 
one-half  mile,  the  broadest  being  at  Kishwaukee  River. 

The  middle  belt  appears  in  western  Kane  County  at  Burlington.  A 
morainic  spur  is  found  to  lead  southwestward  from  the  inner  border  of  the 
outer  belt  into  eastern  Dekalb  County,  and  to  fade  away  2  miles  east  of 
Sycamore.  It  is  about  1  mile  in  width,  and  is  characterized  by  numerous 
basins  and  low  knolls,  which  give  it  fully  as  strong  expression  as  the  neighbor- 
ing portion  of  the  outer  belt,  from  which  it  is  separated  by  a  narrow  plain  1 J 
or  2  miles  in  width.  There  is  also  a  basement  ridge  wdth  a  relief  of  perhaps 
20  feet.  For  several  miles  west  from  the  points  where  the  Burlington  spur 
dies  out,  knolls  10  to  26  feet  high  are  rather  numerous  and  constitute  a 
probable  line  of  continuation.  Near  Malta  a  definite  ridge  appears,  which 
leads  southwestward  to  the  outer  belt  in  the  southwest  corner  of  Malta 
Township,.  Dekalb  County,  and  thence  southward  along  the  east  border  of 
the  outer  belt,  through  western  Milan  and  northwestern  Shabbona  town- 
ships, passing  just  east  of  the  village  of  Lee.  For  3  or  4  miles  in  western 
Milan  Township  it  is  combined  with  the  outer  belt,  but  elsewhere  it  is 
separated  from  it  by  a  narrow  plane  tract  about  a  mile  in  average  width. 
In  western  Shabbona  Township,  Dekalb  County,  it  becomes  completely 
united  with  the  outer  belt.  This  ridge,  like  the  Burlington  spur,  is  about  a 
mile  in  average  width.  It  has  a  relief  of  20  to  40  feet  above  the  bordering 
plane  tracts.  Its  surface  is  gently  undulating,  but  basins  are  rare,  except 
where  it  is  closely  associated  with  the  outer  belt  in  Milan  Township.     The 


248  THE  ILLINOIS  GLACIAL  LOBE. 

altitude  of  the  ridge  just  discussed  is  about  as  great  as  that  of  the  outer 
belt,  aud  it  constitutes  the  source  of  several  of  the  streams  which  lead 
through  the  outer  belt,  viz,  Owen's  Creek,  Killbuck  Creek,  Kite  River,  and 
Willow  Creek. 

By  returning  again  to  western  Kane  County,  to  Elburn,  where  the 
inner  member  leaves  the  composite  belt,  and  tracing  the  moraine  Avestward, 
it  is  found  to  take  a  more  direct  course  than  the  outer  one.  It  leads  nearly 
due  west  for  about  10  miles,  being  throughout  much  of  the  distance  between 
Elburn  and  Cortland  in  ^sdew  from  the  Chicago  and  Northwestern  Railway. 
Immediately  south  of  Cortland  it  changes  to  a  southwestward  trend  and 
joins  the  outer  belt  for  a  few  miles  in  southwestern  Shabbona  Township, 
Dekalb  County,  and  eastern  Wyoming  Township,  Lee  County,  at  the 
southwestern  limits  of  the  section  of  the  morainic  system  under  discussion. 
Throughout  much  of  this  distance  it  has  a  well-defined  crest  and  occupies 
a  widtli  of  1  to  2  miles.  For  a  few  miles  at  the  curving  portion  southwest 
of  Cortland  it  presents  two  ridges  separated  by  a  sag  or  plane  tract  about 
a  mile  in  width  that  stands  20  to  30  feet  below  the  level  of  the  crests  of 
the  ridges.  In  western  Kane  County  several  sharp  gravel  knolls  30  to  40 
feet  in  height  are  found  in  this  belt,  and  occasionally  sharp  knolls  are  found 
in  it  farther  west.  As  a  rule,  howcA^er,  its  undulations  are  gentle.  The 
crest  stands  only  20  to  40  feet  above  the  district  to  the  north,  but  there  is 
a  descent  of  nearly  100  feet  within  a  couple  of  miles  on  the  south  border. 
On  the  slope  there  are  low  knolls  and  a  gently  undulating  surface.  At  its 
junction  with  the  outer  border  belt  in  Shabbona  and  Wyoming  townships 
numerous  basins  and  sharp  knolls  occiu-.  The  knolls  are  in  some  cases 
30  or  40  feet  in  height,  though  usually  20  feet  or  less.  This  inner  moraine 
forms  the  divide  between  South  Kishwaukee  River  and  several  tributaries 
of  Fox  River,  and  is  not  crossed  by  any  stream  east  of  its  junction  with 
tlic  outer  belt.  Near  the  point  of  junction  south  of  Shabbona  it  is  crossed 
by  Indian  C*reek,  a  tributary  of  Fox  River,  which  headKS  in  the  combined 
belt  aud  flows  southwestward.  In  its  course  through  this  moraine  the  creek 
winds  aI)out  greatly  among  the  knolls  and  has  not  so  broad  a  passage  as  is 
afforded  tlie  stniaius  wliich  lead  northward  across  the  outer  belt. 

In  the  Bureau  Creek  drainage  basin. TllC      SCCOud      SGCtioU      of      tllC       BloOmiugtOU 

morainic    system,   which   embraces   tlic   ilrainage  basin   of  Bureau   Creek, 
maintains    a    belt   (in   its   outer  border   fully  as   jironiincut   as   that   of   the 


THE  BLOOMINGTOjST  MOEAINIC  SYSTEM.  249 

section  just  discussed,  but  its  inner-border  belt,  as  noted  above,  loses  its 
strength  in  eastern  Bureau  County,  and  in  the  vicinity  of  the  Illinois 
River  rises  only  a  few  feet  above  the  inner-border  plain.  With  the  decline 
of  this  belt  a  still  later  belt  appears  on  the  plain  to  the  east,  as  noted 
above.  The  two  main  belts  are  closely  associated  for  about  20  miles  in 
southern  Lee  County,  being  separated  only  by  a  narrow  plain  1  to  2  miles 
m  width,  tlii'ough  the  midst  of  which  Bureau  Creek  has  its  jjassage.  They 
then  diverge,  the  course  of  the  inner  one  being  slightly  west  of  south, 
through  eastern  Bureau  County,  while  the  outer  continues  with  a  course 
slightly  south  of  west  along  the  borders  of  Lee  and  Bureau  counties  for  a 
distance  of  20  miles.  It  there  turns  southward  through  central  Bureau 
County,  curving  around  the  western  border  of  the  Bureau  Creek  Basin 
and  passing  just  west  of  Wyanet  and  Tiskilwa.  The  plain  between  the 
moraines  in  Bureau  County  has  a  gently  undulating  surface  and  stands 
nearly  as  hig'h  as  the  inner  moraine,  but  is  much  lower  than  the  outer  one. 
There  is,  in  this  plain,  a  slight  tendency  to  ridging,  with  NE.-SW.  trend, 
which  to  some  extent  governs  the  course  of  sti'eams. 

The  outer  belt  throughout  its  course  in  southern  Lee  and  northern  and 
central  Bureau  counties  maintains  a  width  of  4  to  6  miles.  This  includes 
gradual  slopes  which  culminate  in  a  well-defined  narrow-crested  ridge  that 
is  developed  along  a  considerable  portion  of  the  section  under  discussion. 
The  crested  ridge  usually  occupies  a  breadth  of  less  than  a  mile,  and  stands 
30  to  50  feet  above  the  less  sharply  ridged  portions  on  its  borders.  In 
places  the  sharp  crest  is  absent  and  the  gradual  slopes  occupy  its  entire 
breadth.  Near  Wyanet  a  narrow  depression  as  low  as  the  outer-border 
plain  interrupts  this  ridge  and  furnishes  a  passage  for  the  Hennepin  Canal, 
now  under  construction.  This  depression  is  not  an  open  valley,  but  has 
morainic  knolls  on  its  bottom  and  slopes. 

In  southern  Lee  County  the  knolls  and  undulations  on  the  slopes 
of  the  moraine  are  much  less  conspicuous  than  in  Bureau  County,  their 
height  usually  being  but  10  or  20  feet,  while  in  Bureau  Count}^  they 
frequently  attain  a  height  of  30  or  40  feet.  Basins  are  common  only  in 
central  Bureau  County,  though  they  are  found  occasionally  in  other  parts 
of  the  moraines.  The  deepest  are  only  10  or  15  feet  below  the  bordering 
rims,  and  their  area  is  seldom  more  than  an  acre  or  so  each.  On  the  outer 
face  of  the  moraine  in  Lee  Countv,  from  the  vicinity  of  the  Third  Principal 


250  THE  ILLINOIS  GLACIAL  LOBE. 

Meridian  westward  to  northern  Bureau  County,  there  are  numerous  sand 
knolls  and  ridges,  10  to  40  feet  in  height,  which  add  greatl}^  to  the  inequal- 
ities of  the  surface.  These  sand  accumulations  follow  the  lines  of  ridges  or 
knolls  in  the  moraine,  rather  than  the  depressions  between  them.  The  sand 
is  still  subject  to  slight  moditication  by  wind  action,  and  its  ridg-es,  as  well 
as  its  presence  on  the  moraine,  are  probably  the  result  of  wind  transportation 
from  the  Green  River  Basin,  which  borders  this  portion  of  the  moraine  on 
the  west. 

The  inner  belt  of  this  system,  as  noted  above,  is  merged  with  the  outer 
from  the  vicinity  of  Shabbona  southwestward  to  Pawpaw,  and  presents  a 
knob-and-basin  topography  along  the  line  of  junction.  Upon  separating 
from  the  outer  belt  the  topograpliy  changes  to  gentle  undulations,  and 
there  is  also  a  tendency  to  ridging  in  the  line  of  the  belt.  In  places  a  cross 
section  would  lead  over  at  least  three  nearly  parallel  ridges  separated  by 
narrow  sags,  the  Avhole  series  occupying  a  width  of  scarcely  2  miles.  The 
ridges  are,  however,  not  distinctly  maintained  for  long  distances,  but  are  at 
intervals  crowded  together.  These  ridges  are  of  about  equal  height  and 
rise  only  25  to  50  feet  above  the  plain  on  their  outer  border.  The  relief 
on  the  inner  or  southeast  border  is  nearly  150  feet  in  eastern  Lee  County, 
and  this  great  relief  is  maintained  for  10  or  12  miles  southwestward  in  south- 
eastern Lee  and  northwestern  Lasalle  counties.  Upon  Entering  Bureau 
County  the  relief  decreases  rapidly,  as  already  noted,  but  the  expression 
continues  as  strong  as  in  the  portion  having  greater  relief  Knolls  20  feet 
or  more  in  height  are  closely  aggregated,  and  are  disposed  in  chains  trending 
in  line  with  the  belt.  Upon  approaching  the  Illinois  Valley  they  become 
more  scattering,  and  the  belt  fades  out  about  2  miles  north  of  Depue.  The 
feebly  developed  portion  ()f  this  belt  is  shown  in  the  northwest  corner  of 
the  Lasalle  topograpliic  sheet  and  in  the  eastern  part  of  the  Hennepin 
sheet  between  East  Bureiiu  and  Brusli  creeks.  The  ridge  which  leads  south- 
ward from  Earlville  past  Utica,  a  few  niiles  east  of  this  moraine,  is  discussed 
farther  on,  as  is  also  the  topography  in  the  line  of  continuation  of  this  moraine 
in  Putnam,  Marshall,  Woodford,  and  McLean  counties.     (See  pp.  261,  281.) 

In  Bureau,  Marshall,  and    Peoria  counties TllC     third     SCCtioU      of     thc       BloOmillS'tOn 

morainic  system  onibr:ices  tlu^  })ortion  of  the  moraine  west  of  the  Illinois 
River  in  Bureau,  MarsliMll,  nnd  Peiiri;i  counties.  This  consists  niainh'  of 
a  large  ridge,  4  to  6  miles  in  \vi(hli  ninl   100  feet  or  more  in  height  above 


THE  BLOOMIKGTOJSr  MOEAINIO  SYSTEM.  251 

the  districts  on  the  west  and  an  even  greater  height  above  the  narrow  plain 
between  the  ridge  and  the  river  bkiff.  Aside  from  this  main  ridge  there  are 
minor  ridges  trending  parallel  with  it  on  its  inner  or  eastern  border.  These 
minor  ridges  are  a  mile  or  less  in  width,  25  to  50  feet  in  height,  and  are 
maintained  for  only  a  few  miles  in  a  place.  The  surfaces  are  much  smoother 
than  that  of  the  main  ridge.  They  are  similar  to  the  slight  ridgings  found 
between  the  inner  and  oiiter  belts  in  eastern  Bureau  County,  and,  like  those 
ridg'es,  have  an  influence  on  the  course  of  drainage.  One  of  the  most  con- 
spicuous instances  of  the  governing  of  drainage  is  that  of  Senachwine 
Creek,  in  southwestern  Marshall  County,  which  owes  its  southward  course 
to  a  low  drift  ridge  on  its  east  border. 

The  main  ridge  has  a  topography  similar  to  that  of  its  northern  con- 
tinuation in  central  and  northern  Bureau  County.  In  places  a  sharplj?^ 
outlined  crest  is  developed,  but  usually  the  higher  part  of  the  ridge  is 
broken  up  into  knolls  and  sharp  disjointed  ridges  which  rise  20  to  40  feet 
above  neighboring  basins  or  sags.  Shallow  basins  are  a  common  feature 
along  this  portion  of  the  moraine.  On  the  outer  face  the  border  is  irregular, 
being  indented  hj  valley-like  extensions  of  the  outer-border  plain,  which 
in  some  cases  reach  a  mile  or  more  back  into  the  moraine.  Between  these 
indentations  there  are  spur-like  projections.  The  moraine  is  nowhere  cut 
through  by  any  of  these  low  tracts,  though  a  line  along  its  crest  occasion- 
ally oscillates  100  feet  or  more  within  a  space  of  2  or  3  miles.  On  the 
whole,  this  section  is  scarcely  surpassed  in  strength  by  any  other  portion  of 
this  morainic  system. 

Between  the  Illinois  and  Mackinaw  rivers. Tlie    SeCtioU    embraCCd    betweCU  the  Illi- 

nois  and  Mackinaw  rivers  has  a  well-defined  outer  or  southwest  border,  but 
its  inner  or  northeast  border  is  difiicult  to  determine.  It  merges  on  the 
northeast  into  an  elevated  tract  with  a  gently  undulating  surface,  whose 
general  altitude  is  about  as  great  as  tha,t  of  the  portion  of  the  belt  which 
presents  stronger  morainic  expression.  This  elevated  tract  extends  as  far 
east  as  Cazenovia.  Should  the  entire  district  between  Cazenovia  and  the 
outer  border  be  included  in  the  moraine,  it  would  have  a  breadth  of  about 
14  miles,  or  more  than  twice  the  breadth  of  the  bulky  outer  ridge  formed  on 
the  west  side  of  the  river.  The  strongly  morainic  expression  is  confined, 
however,  to  the  outer  or  southwest  face  in  a  belt  only  3  or  4  miles  in 
width.     This  face  presents  a  series  of  drift  billows  20  to  30  feet  in  height, 


252  THE  1LLI5TOIS  GLACIAL  LOBE. 

among  whicli  are  sags  and  shallow  basins.  The  swells  are  usually  closely 
aggregated,  but  in  places  nearly  plane  tracts  of  a  square  mile  or  more 
appear  in  the  midst  of  this  belt.  An  instance  of  such  a  plane  tract  may 
be  seen  south  of  Deer  Creek  callage.  The  elevated  tract  on  the  northeast 
border  of  this  moraine  has  only  occasional  low  swells  10  or  15  feet  in 
height,  the  greater  part  of  the  surface  being  as  smooth  as  the  plains  farther 
noi'th  and  east,  and  differing  from  them  only  50  to  75  feet  in  altitude.  The 
descent  is  made  in  a  distance  of  2  or  3  miles,  and  is  therefore  so  gradual  as 
to  be  scarcelv  perceptible  to  the  eye.  The  relief  on  the  outer  border  is 
more  conspicuous  than  on  the  inner,  a  rise  of  100  feet  being  made  in  about 
2  miles  at  the  prominent  parts  of  the  moraine.  This  border  is  also  made 
conspicuous  by  the  change  from  the  A^ery  flat  surface  outside  the  moraine 
to  the  billowy  surface  presented  by  its  outer  face. 

Between  Mackinaw  River  and  the  Ford  County  reentrant. EaSt  of    tllC   MackiuaW   River, 

near  the  borders  of  Woodfoi'd,  McLean,  and  Tazewell  counties,  the  Bloom- 
ington  morainic  system  presents  two  well-defined  bulky  ridges  which  are 
separated  by  a  narrow  plain  or  sag  1  or  2  miles  or  more  in  width.  These 
ridges  are  distinctly  maintained  from  the  extreme  northwest  corner  of 
McLean  County  eastward  to  Padua,  a  distance  of  nearly  30  miles,  beyond 
which,  for  20  to  25  miles,  to  the  Ford  County  reentrant,  they  are  combined 
into  a  single  belt. 

The  inner  ridge  enters  McLean  Coi;nty  from  Woodford  County  near 
the  line  of  the  third  principal  meridian  and  passes  soutlieastward  through 
Normal  and  thence  eastward  through  Barnes  to  Padua,  where  it  becomes 
combined  with  the  outer  ridge.  It  has  a  general  width  of  2  or  3  miles  and 
rises  30  to  50  feet  above  the  sag  or  plain  on  its  south  border.  The  surface 
is  billowy,  Avith  oscillations  of  20  or  30  feet  between  the  higher  swells  and 
neighboring  sags.  Many  smaller  swells  occur,  with  a  height  of  5  or  10 
feet.  The  slope  of  these  swells  is  usually  gentle,  and  knolls  20  feet  in 
heiglit  occupy  several  acres.  In  j^laces  this  moraine  presents  a  sharply 
outlined  crest;  a  conspicuous  instance  Avas  noted  northwest  of  Padua,  Avhere 
a  ridge-like  crest  with  a  width  of  only  one-fourtli  to  one-half  mile  stands 
about  50  feet  above  the  tracts  on  either  side.  As  a  rule,  however,  the 
higlier_])()rtion  of  this  belt  consistif  of  a  series  of  swells  similar  to  those  found 
on  tlie  slojjes.     For  several  miles  nortli  from  this  inner  ridge  the  siu'face  is 


THE  BLOOMINGTOlSr  MORAINIC  SYSTEM.  253 

gentl)^  undulating'  and  dotted  with  occasional  knolls  of  considerable  promi- 
nence, the  highest  knolls  rising  30  to  40  feet  above  border  districts. 

The  outer  ridge  crosses  Mackinaw  River  immediately  above  Mack- 
inaw village  and  leads  southeastward  to  Bloomington  and  thence  eastward 
to  its  point  of  junction  with  the  inner  ridge  near  Padua.  It  has  a  breadth 
of  about  3  miles.  It  is  crossed  by  several  streams  which  head  in  the 
inner  ridge,  among  which  are  three  of  the  headwater  branches  of  Sugar 
Creek,  two  headwater  branches  of  Kickapoo  Greek,  and  one  headwater 
branch  of  Salt  Creek.  Sangamon  River  also  leads  tlu-ough  it,  east  from 
the  junction  with  the  inner  ridge.  There  are  thus  seven  streams  crossing 
it  within  a  space  of  35  or  40  miles,  admitting  only  about  5  miles  average 
distance  between  streams.  The  gaps  through  Avhich  these  streams  pass,  each 
cause  a  break  in  the  crest  of  the  moraine  nearly  a  mile  in  width.  They  do 
not  appear  to  be  entirely  erosion  gaps,  for  the  morainic  swells  occupy  them 
down  nearly  to  the  level  of  the  streams,  or  about  75  to  100  feet  below  the 
level  of  the  neighboring  crests.  It  is  probable  that  streams  issuing  from  the 
ice  sheet  at  the  time  the  moraine  was  forming  prevented  the  accumulation 
of  heaver  deposits  in  the  vicinity  of  their  points  of  departure  from  the  ice. 
Between  these  gaps  the  moraine  usually  has  a  well-defined  crest  and  gently 
undulating  surface.  The  crest  lies  near  the  outer  border  of  the  moraine, 
the  outer  face  being,  as  a  rule,  much  more  abrupt  than  the  inner.  As  the 
moraine,  where  not  interrupted  by  gaps,  has  a  relief  of  100  feet,  the  outer 
face  often  presents  the  abruptness  of  a  river  bluff.  It  differs,  however, 
from  a  river  bluff  in  the  absence  of  erosion  contours,  there  being  instead  a 
billowy  slope,  such  as  characterizes  moraines.  The  erosion  effected  by 
streams  since  the  withdrawal  of  the  ice  sheet  is  very  inconspicuous  com- 
pared with  the  inequalities  of  drift  aggregation.  The  crest  is  usually  so 
gently  undulating  as  scarcely  to  suggest  the  strength  of  the  moraine.  It  is 
not  uncommon  to  find  it  so  level  for  a  space  of  one-fourth  to  one-half 
mile  in  width  and  for  several  miles  in  length  that  artificial  ditching  is  neces- 
sary to  give  it  good  drainage.  In  such  places  there  are  usually  shallow 
basins,  2  to  5  feet  in  depth,  occupying  an  acre  or  more  each,  which  add  to 
the  imperfection  of  drainage.  The  crest  varies  considerably  in  altitude 
independent  of  the  gaps  just  mentioned,  its  highest  points  being  about  900 
feet  above  tide  and  its  lowest  about  800  feet.     The  range  of  100  feet  in 


254  THE  ILLINOIS  GLACIAL  LOBE. 

altitude,  however,  occupies  a  space  of  1  to  2  miles  or  more,  and  hence  is 
not  conspicuous.  The  slopes  usually  present  more  undulations  than  the 
crest,  but  their  swells  seldom  exceed  20  feet  in  height. 

The  combined  belt  east  from  Padua  differs  from  the  separate  belts 
farther  west  in  presenting  greater  complexity  of  features.  Between  Padua 
and  Arrowsmith  the  trend  of  the  principal  ridges  is  northwest  to  southeast. 
One  ridge  with  this  trend  passes  immediately  west  of  Ellsworth  and  consti- 
tutes the  divide  between  Sangamon  River  and  Kickapoo  Creek.  Another 
ridge  leads  into  Arrowsmith  from  the  northwest,  which  separates  the  Sanga- 
mon from  the  Mackinaw.  From  the  -sncinity  of  Arrowsmith  eastward  to 
the  reentrant  angle  in  Ford  County  the  trend  of  ridges  is  southwest  to 
northeast,  or  nearly  at  right  angles  with  those  west  of  An-owsmith.  The 
ridges  just  mentioned  are  low,  with  a  relief  of  but  30  or  40  feet.  There  is 
a  prominent  crest  along  the  south  border  of  the  combined  belt  which  is 
interrupted  by  a  small  gap  at  the  Sangamon  Valley.  It  stands  about  100 
feet  above  the  plain  outside  the  moraine,  and  rises  from  that  plain  with  the 
abruptness  of  a  bluff  line.  The  Sangamon  River  winds  about  through  sags 
among  ridges  until  it  emerges  from  this  morainic  belt.  Aside  from  the 
ridges  and  broad  sags  the  moraine  is  characterized  by  a  multitude  of  gentle 
swells  10  or  15  feet  in  height,  among  which  there  are  shallow  sags  and 
occasional  basins. 

The  reentrant  in  Ford  County. — 111  the  reentrant  auglc  ill  Ford  couuty  the  ridges 
on  the  west  are  crowded  together  in  a  single  belt,  but  those  on  the  east 
are  in  pait  separated  b}^  narrow  strips  of  level  marshy  land  which  trend 
witli  the  belt  from  north-northwest  to  south-southeast.  The  topography 
of  the  greater  part  of  the  reentrant  portion  is  of  a  gentle  swell-and-sag 
type,  with  undulations  of  only  15  or  20  feet.  The  ridges  have  definite 
crest  lines  standing  about  50  feet  above  the  marshy  plains  which  separate 
them.  In  southeastern  Livingston  Count}',  however,  at  the  extreme  north 
end  of  the  reentrant,  a  sharp  knob-and-basiu  topography  is  developed,  in 
which  knolls  rise  abruptly  30  or  40  feet  above  the  basins  inclosed  among 
them.  There  are  several  small  lakes  and  ponds  among  the  morainic  knolls, 
the  largest  of  wliicli  occupy  areas  of  40  acres  or  more,  but  the  majority 
occupy  only  a  few  acres  each.  From  this  jioiiit  of  the  reentrant  angle 
there  is  more  or  less  knob-and-basiu  topography  develo])ed  along  the  inner 
or  northeastern  slope  of  the  moraine  tln-oughout  its  southeastward  course 


THE  BLOOMINGTOISr  MOEAINIO  SYSTEM.  255 

in  eastern  Ford  and  southwestern  Iroquois  counties.  It  is  confined  to  a 
belt  about  3  miles  in  width,  and  probably  half  the  surface  is  of  this  type. 
The  remainder  is  of  a  gentle  swell-and-sag  type.  The  expression  is  more 
subdued  than  at  the  point  of  the  reentrant  angle,  and  knolls  exceeding  30 
feet  in  height  are  rare.  The  basins  are  seldom  occupied  by  j)onds  except 
in  wet  seasons.  The  contrast  between  this  knob-and-basin  tract  and  the 
gentlj^  undulating'  crest  line  of  the  moraine  is  quite  striking. 

Eastward  from  the  Ford  County  reentrant  to  western  Indiana. Tlie    SCCtion    Ot     the     BloOUl- 

ington  morainic  system  east  from  the  reentrant  angle  presents  a  series  of 
ridges  grouped  in  two  belts.  The  outer  belt  throughout  its  course  in 
southern  Ford  and  northeastern  Chamj^aign  counties  consists  of  a  single 
broad  ridg-e  with  billowy  surface,  having  oscillations  of  20  to  30  feet.  As  a 
rule,  a  well-defined  crest  is  developed,  but  in  places  it  completely  disappears 
and  the  belt  consists  entirely  of  knolls  and  winding  ridges,  among  which 
sags  and  shallow  basins  occur.  Upon  entering  Vermilion  County  the  outer 
belt  soon  disj)la3^s  a  double-crest  line,  and  in  the  eastern  part  of  the  county 
is  separated  into  two  ridges,  as  shown  on  the  Dan\alle  topographic  sheet, 
between  which  there  is  a  narrow  j^lain  tract  a  mile  or  more,  in  width  that 
is  drained  by  Stony  Creek.  This  plain,  however,  is  present  for  only  a 
few  miles,  the  ridges  as  a  rule,  being  closely  associated.  The  surface  of 
the  ridges  varies  from  gently  undulating  to  strongly  billowy.  The  billows 
are  seldom  greater  than  30  feet  in  height.  The  moraine  varies  75  or  100 
feet  in  altitude  in  Vermilion  County,  but  the  variation  is  not  abrupt,  a 
fluctuation  of  50  or  75  feet  usually  occupying  2  miles  or  more.  It  rises 
very  promptl}'  on  its  south  border,  especially  in  the  western  part  of  the 
county.  In  Warren  County,  Indiana,  this  belt,  or  at  least  its  inner  part, 
curves  around  gradually  to  the  northward  and  constitutes  the  divide  between 
Vermilion  River  and  Pine  Creek.  It  is  overridden  in  northern  Warren 
County  by  a  moraine  of  the  late  Wisconsin  series,  which  has  not  obliterated 
it,  but  has  simply  dotted  the  surface  with  small  knolls,  the  majority  of 
which  are  less  than  10  feet  in  height.  The  outer  belt  joins  the  inner  in 
northern  Warren  County  and  the  combined  belt  passes  northeastward  into 
Benton  County,  as  indicated  below. 

Between  the  outer  and  inner  belts  of  the  portion  of  the  Bloomington 
morainic  system  east  of  the  reentrant  angle  is  a  narrow  plain  with  very 
smooth  surface,  there  being  scarcely  a  knoll  or  undulation  so  much  as  10 


256  THE  ILLINOIS  GLACIAL  LOBE. 

feet  in  height.  This  plain  sets  in  in  southeastern  Livingston  County,  within 
5  or  6  miles  of  the  extreme  north  end  of  the  reentrant,  and  is  continuous 
through  Ford,  Champaign,  and  Vermilion  counties,  Illinois,  and  western 
Wan'eu  County,  Indiana.  Its  greatest  width  is  in  Vermilion  County, 
where  it  reaches  a  breadth  of  7  or  8  miles,  a  portion  of  it  extending  into 
the  northwest  part  of  the  area  shown  on  the  DauAalle  sheet.  Its  breadth 
in  Ford  and  Champaign  counties  is  2  to  5  miles. 

The  inner  belt  of  this  morainic  system  presents  two,  and  in  places 
three,  crests  in  eastern  Ford  County.  One  crest  leads  from  the  point  of  the 
reentrant  southwai'd  thi-ough  Mehau,  between  two  branches  of  the  Ver- 
milion River,  to  the  vicinity  of  Henderson,  where  it  crosses  the  eastern 
branch  just  above  its  junction  with  the  western,  and  leads  southeastward 
through  Paxton  along  the  north  border  of  the  river  into  Vermilion  County. 
Another  crest  appears  about  3  miles  south  of  Roberts  and  leads  southeast- 
ward, parallel  with  the  crest  just  mentioned,  crossing  the  exti-eme  southwest 
comer  of  Iroquois  County  and  fading  out  east  of  Paxton.  A  third  crest 
leads  from  the  extreme  north  end  of  the  reentrant  near  Chatsworth,  in  Liv- 
ingston County,  in  a  course  east  of  south,  past  Pope's  Grove  and  Roberts, 
into  southwestern  Iroquois  County  near  Loda,  beyond  which  it  is  diffi- 
cult to  trace.  It  is  on  the  slope  of  the  third  ridge  that  the  knob-and-basin 
topogi'aphy  above  mentioned  is  developed.  None  of  the  three  crest  ridges 
Avhieh  this  inner  belt  presents  in  Ford  County  and  adjacent  districts  have 
strong  expression.  The  outer  one  stands  30  to  50  feet  above  the  plain  tract 
outside  (west)  of  it,  but  is  not  so  prominent  on  its  inner  border.  The  other 
ridges  rise  only  20  to  30  feet  above  the  border  tracts.  These  crest  ridges 
each  have  a  breadth  of  half  a  mile  or  more.  In  a  few  places  the  outer 
crest  can-ies  knolls  20  or  30  feet  in  height.  The  outer  crest  is  also 
more  winding  than  the  others,  and  has  a  border  indented  bv  extensions  of 
the  plain  which  enter  it  a  half  mile  or  more. 

In  Vermilion  and  Iro(|Uois  counties,  Illinois,  and  Benton  Countv,  Indi- 
ana, this  inner  belt  has  a  well-detined  crest  which  forms  the  divide  between 
the  Iroquois  and  Vermilion  rivers  and  which  stands  3  or  4  miles  back  from 
the  inner  border  of  the  moraine.  This  crest  and  the  inner  slope  are  gently 
midulating,  with  swells  10  to  20  feet  in  height.  There  is  a  gradual  north- 
ward descent  of  perhaps  20  feet  per  mile  to  the  inner-border  plain.  The 
crest  usually  is  similnr  to  tlic  inner  slope,  but  orcasionallA'  is  sharplv  ridged, 


THE  BLOOMINGTOK  MORAmiC  SYSTEM.  257 

as  in  the  south  part  of  T.  23,  Rs.  13  and  14  W.,  where  it  rises  abruptly  30 
feet  or  more  above  the  bordering-  portion  of  the  moraine  in  a  narrow  belt  a 
half  mile  or  less  in  width.  South  from  the  crest  just  mentioned  there  is,  in 
Vermilion  and  Warren  counties,  another  ridg-e  interrupted  by  occasional 
gaps.  The  ridge  is  continuous  from  the  north  fork  of  Vermilion  River  near 
Rossville  eastward  to  its  junction  with  the  outer  morainic  belt  at  Pine 
Creek  in  northern  Warren  and  southern  Benton  counties.  West  from  Ross- 
ville it  can  be  traced  in  a  curving  course  southwestward  to  the  Middle 
Vermilion,  near  Potomac,  and  thence  northwestward  up  the  north  side  of 
that  stream.  It  is  interrupted  by  a  gap  a  mile  or  more  in  width  immedi- 
ately north  of  Potomac,  and  is  deeply  indented  by  valley-like  sloughs  at 
points  farther  east.  In  the  vicinity  of  Blue  Grass,  in  western  Vermilion 
County,  there  is  a  plain  occupying  several  square  miles  which  separates 
this  ridge  from  the  one  north  of  it.  There  is  also  a  plain  between  the  two 
ridges  from  the  bend  of  Vermilion  River  south  of  Hoopstown  eastward  into 
Indiana  as  far  as  the  ridges  are  traceable.  The  plain  is  scarcely  2  miles  in 
width  in  the  Illinois  portion,  but  reaches  a  width  of  3  or  4  miles  in  Indiana. 
The  south  ridge  of  this  inner  belt  has  usually  a  relief  of  about  50  feet 
above  the  plain  on  the  south,  and  slightly  less  above  the  plane  tracts 
lying  between  it  and  the  north  ridge.  It  is  2  or  3  miles  in  width,  and 
its  crest  lies  nearer  the  south  than  the  north  border.  Its  topographj^  is 
similar  to  that  of  the  north  lidge,  there  being  a  gently  undulating  surface 
with  few  knolls  more  than  20  feet  in  height. 

The  portion  covered  by  late  Wisconsin  drift. Tllis  mOraiuic  SyStOm  is  COUSpicUOUS  for 

15  or  20  miles  within  the  limits  of  the  late  Wisconsin  drift,  and,  as  noted 
above,  probably  embraces  the  belt  of  thick  drift  which  leads  eastward 
through  central  Indiana  into  Ohio.  The  north  ridge  maintains  its  usual 
strength  to  the  vicinity  of  Fowler,  Indiana,  where  it  terminates  abruptly 
in  a  marshy  tract.  The  remainder  of  the  belt  swings  around  the  eastern 
end  of  the  north  ridge  and  dies  out  in  a  gently  undulating  tract  2  or  3  miles 
east  of  Fowler. 

It  is  a  question  whether  the  ridges  in  Benton  County  have  suffered 

much  reduction  by  the  late  Wisconsin  ice  invasion.     That  invasion  formed 

onl}^  weak  moraines  in  this  district,  consisting  usually  of  belts  of  low  knolls 

only  5  or  10  feet  in  height,  which  are  accompanied  by  a  gi'eat  number  of 

MON  xxxviii 17 


258  THE  ILLINOIS  GLACIAL  LOBE. 

bowlders,  whose  distribution  in  belts  was  long  since  noted  by  members  of 
tlie  Indiana  survey.  These  belts  of  knolls  and  bowlders  cross  the  ridg-es 
and  intervening  plains  of  the  Bloomington  system  nearly  at  right  angles  in 
a  NNW.-SSE.  course,  as  may  be  seen  by  reference  to  the  glacial  map 
(PI.  VI).  They  assume  greater  strength  a  few  miles  to  the  north,  there 
being  a  prominent  morainic  belt  in'  northwestern  Benton  and  eastern 
Iroquois  counties,  near  the  border  of  Illinois  and  Indiana.  In  this  connec- 
tion it  may  be  remarked  that  the  outer  moraine  of  the  late  Wisconsin 
system  is  very  variable  in  strength  from  place  to  place,  and  has  a  develop- 
ment about  as  weak  in  its  passage  across  the  Bloomington  morainic  system 
as  in  any  pai't  of  its  course. 

The  weak  moraine  in  eastern  Iroquois  County,  Illinois. Of  tllC  WCak  mOraiuCS   COnUCCtcd 

with  the  Bloomington  system  the  first  to  receive  consideration  is  the  one 
which  emerges  from  beneath  the  late  Wisconsin  series  near  the  Illinois- 
Indiana  line  and  passes  westward  into  Iroquois  County.  This  is  main- 
tained as  a  distinct  ridge,  20  to  40  feet  in  height  and  scarcely  more  than  a 
mile  in  width,  for  a  distance  of  about  8  miles  west  from  the  State  line, 
where  it  dies  a,waj  on  the  border  of  Sugar  Creek.  It  has  a  gently  undu- 
lating surface,  the  swells  seldom  exceeding  10  feet  in  height.  The  probable 
continuation  of  this  ridge  is  found  in  a  poorly  defined,  undulatory  belt  which 
appears  on  the  west  side  of  Sugar  Creek  opposite  the  end  of  this  ridge  and 
leads  westward  to  Onarga.  It  stands  scarcely  20  feet  above  the  bordering 
plains  on  either  side  and  its  surface  is  but  little  more  undulatory  than  that 
of  the  2)lains.  Its  slight  relief,  however,  is  a  matter  of  considerable  conse- 
quence, since  it  stands  too  high  for  flowing  wells  to  be  obtained,  while  the 
neighboring  plains  furnish  a  large  number  of  flowing  wells  from  the  drift. 
This  belt  does  not  connect  definitely  with  the  bulky  ridges  at  the  west,  but 
as  it  is  separated  from  them  by  a  space  of  onlj^  3  or  4  miles  it  seems  to  fall 
naturally  into  the  same  system. 

cropsey  Ridge. — Froui  tho  wcst  sidc  of  the  reentrant  angle  in  southeastern 
Livingston  County  a  small  ridge  leads  westward,  as  already  noted,  past 
Cropsey,  across  northern  McLean  County,  forming  a  divide  between  the 
Mackinaw  and  Illinois- Vermilion  drainage  basins.  The  portion  east  from 
Cropsey  stands  30  to  50  fiict  above  tlie  plain  on  the  south,  and  in  places 
presents  a  very  abrupt  relief  on  that  border.     Toward  the  north  it  has  a 


THE  BLOOMINGTOK  MOEAINIG  SYSTEM.  259 

more  gradual  descent  to  a  plain  wliicli  continues  descending  to  the  Vermilion 
River.  This  eastern  portion  of  the  ridge  has  numerous  small  knolls  10  to 
20  feet  in  height  and  occasional  shallow  basins.  From  Cropsey  westward 
the  expression  is  somewhat  weaker,  though  a  relief  of  fully  30  feet  is  main- 
tained as  far  west  as  the  Chicago  and  Alton  Railroad  north  of  Lexington. 
There  is  also  sufficient  undulation  of  the  surface  to  give  this  belt  decided 
contrast  to  the  plains  on  its  border,  swells  10  to  20  feet  in  height  being  quite 
common.  West  from  the  railroad  the  belt  is  definitely  ridged  for  a  few  miles, 
but  near  Elpaso  it  becomes  so  obscure  that  further  tracing  and  coixelation 
has  not  been  attempted.  There  are  many  places  toward  the  north  and  west, 
in  northeastern  Woodford,  eastern  Marshall,  southwestern  Lasalle,  and  east- 
ern Putnam  counties,  where,  for  a  space  of  a  square  mile  or  more,  the  surface 
is  quite  as  undulatory  as  in  this  morainic  belt.  It  is  possible  that  more 
detailed  study  will  bring  out  a  connection  between  these  several  undulatory 
tracts  by  which  they  may  be  thrown  into  a  single  belt.  Possibly  the  divide 
between  Vermilion  River  and  tributaries  of  the  Illinois  flowing  directly 
westward  will  prove  to  be  the  axis  of  such  a  belt.  This  divide,  wherever 
it  has  been  crossed  by  the  writer,  presents  a  slightly  undulatory  surface. 
The  majority  of  the  strongly  undulatory  belts,  however,  are  found  a  short 
distance  west  of  this  divide.  The  surface  is  generally  more  undulatory 
west  from  the  divide  than  east  from  it. 

chatsworth-cayuga  Ridge. — From  tlic  reentrant  angle  at  Chatsworth  in  south- 
eastern Livingston  County  northwestward  nearly  to  Forrest  the  inner  of  the 
two  weak  members  of  this  morainic  system  has  sharp  knolls  inclosing  basins, 
but  their  height  is  less  than  in  the  reentrant  angle,  seldom  exceeding  25  feet. 
They  occur  on  the  slope  as  well  as  on  the  crest  of  the  moraine.  From  the 
vicinity  of  Forrest  northwestward  for  a  few  miles  the  moraine  has  a  well- 
defined  crest  and  is  characterized  by  gentle  swells  10  to  20  feet  high.  In 
sec.  34,  Pleasant  Ridge  Township  (T.  27,  R.  7  E.),  the  single  crest  gives 
place  to  a  double  one,  and  two  ridges  are  maintained  from  this  point  north- 
westward to  the  north  branch  of  the  Illinois-Vermilion  River,  the  outer  ridge 
coming  to  that  river  in  sec.  14,  T.  27,  R.  6  E.,  while  the  inner  comes  to  it  in 
sees.  7  and  8,  T.  27,  R.  7  E.  The  outer  ridge  has  a  billowy  crest,  consisting 
of  a  series  of  slightly  elliptical  knolls,  25  to  40  feet  high,  40  to  50  rods 
long,  and  about  one-half  as  wide.     These  constitute  an  almost  complete 


260  THE  ILLINOIS  GLACIAL  LOBE, 

chain  leading  from  the  river  to  the  point  of  junction  with  the  ijuer  ridge. 
The  inner  ridge  has  not  sucli  a  crest  but,  instead,  a  gentle  swell-and-sag 
topography,  with  undulations  of  20  to  25  feet. 

At  the  east  branch  of  the  Illinois- Vermilion  River  this  morainic  belt  is 
interrupted  by  a  plain  nearly  2  miles  in  width.  The  ridges  are,  however, 
both  present  north  of  the  river.  The  outer  one  appears  in  sees.  33  and  34, 
Owego  Township,  and  bears  slightly  west  of  north  to  Cayuga.  The  inner 
appears  in  sec.  31,  Saunemin  Township,  and  bears  northward  about  2  miles, 
and  is  interrupted  by  a  gap  through  which  Felkey  Creek  has  its  passage. 
It  appears  on  the  west  side  of  this  creek  and  bears  northwestward,  joining 
the  outer  one  near  Cayuga.  Each  of  these  ridges  has  a  gently  undulating 
sm-face,  but  upon  becoming  coalesced  a  sharply  undulatory  topography 
sets  in,  in  which  the  swells  stand  30  to  40  feet  above  the  bordering  sags 
and  sloughs. 

From  Cayuga  northwestward  to  northern  Li^angston  County  the 
moraine  under  discussion  is  so  closely  associated  on  the  inner  border  with 
the  Marseilles  moraine  as  to  be  obscured  by  it,  and  is  interrupted  by  sev- 
eral gaps  where  creeks  tributary  to  the  Illinois- Vermilion  River  traverse  it. 
These  gaps  occur  at  the  following  sti'eams:  Wolf  Creek,  Deer  Creek, 
Baker's  Run,  Mud  Creek,  and  Blackstone  Creek.  The  gaps  are  a  mile  or 
less  in.  width,  while  the  ridges  which  lie  between  them  occupy  a  length  of  2 
or  3  miles.  These  inteiTupted  ridges  consist  of  a  series  of  billows  ranging 
in  height  from  10  feet  up  to  40  feet  or  more.  The  most  prominent  one 
noted  is  in  sec.  18,  T.  30,  R.  5  E.,  and  is  known  as  "Smith's  Mound."  It 
occupies  about  40  acres  and  stands  nearly  50  feet  above  the  surrounding 
countrj'.     Basins  occur  on  its  summit. 

Farm  Ridge  or  Grand  Ridge. — In  soutliem  Lasallc  Couuty,  just  east  of  Sti'eator, 
as  noted  abo%'e,  a  morainic  ridge  known  as  Farm  Ridge  and  also  as  Grand 
Ridge  emerges  from  the  outer  border  of  the  Marseilles  moraine.  It  appears 
to  be  the  continuation  of  the  Chatsworth-Cayugsi  Ridge.  For  a  few  miles, 
to  Otter  Creek  Valley,  it  is  sepai-ated  from  the  Mai-seilles  moraine  by  a 
naiTOw  valley-like  plain  scarcely  a  mile  in  ^^'idth.  In  sees.  29  and  30, 
T.  31,  R.  4  E.,  it  carries  sharp  knolls,  but  the  remainder  of  the  ridge  in 
the  interval  between  tlie  county  line  and  Otter  Creek  has  a  gently  undu- 
lating surface.     At  Otter  Creek  there  is  a  break   a  mile  or  so  in  width. 


THE  BLOOMINGTON  MOEAIFIO  SYSTEM.  261 

Nortli  of  the  creek  the  moraine  consists  of  a  series  of  knolls  and  sharp 
ridges  standing-  20  to  60  feet  above  bordering  valleys  or  depressions. 

In  the  southeast  part  of  T.  32,  R.  4  E.,  the  moraine  swings  abruptly 
-westward,  passing  through  the  village  of  Grand  Ridge  to  Farm  Ridge  post- 
office.  It  carries  knolls  which  rise  to  a  height  of  20  feet  or  more.  Between 
Grand  Ridge  and  Farm  Ridge  the  topography  is  of  a  subdued  knob-and- 
basin  type.  From  Farm  Ridge  to  the  Illinois  bluff  near  Utica  there  is  a 
smooth  ridge  with  very  gentle  undulations,  but  with  a  well-defined  relief 
of  20  or  30  feet.  This  ridge  is  in  places  capped  by  sandy  knolls  10  to  15 
feet  in  height,  apparently  wind  drifted. 

The  portion  of  this  moraine  north  of  the  Illinois  River  consists  of 
three  disjointed  ridg-es  arranged  end  to  end,  but  varying-  greatly  in  the 
direction  which  they  trend.  They  maj  be  traced  readily  on  the  Lasalle 
and  Ottawa  topographic  sheets.  The  southern  one  has  its  southern  termi- 
nus at  the  north  bluff  of  the  Illinois  River  between  Little  Vermilion  River 
and  Pecumsaugen  Creek.  It  leads  northward  through"  Lasalle  Township 
for  2  miles  or  more,  then  curves  slightly  and  turns  east  of  north,  passing 
through  sees.  30,  19,  17,  9,  and  4,  Waltham  Township.  It  then  drops  down 
rapidly  just  north  of  the  township  line.  The  second  ridge  appears  within 
a  mile  northeast  of  its  terminus,  and  bears  slightly  west  of  north  for  a 
distance  of  about  3  miles,  when  it  also  drops  off  suddenly  near  Tomahawk 
Creek.  North  of  Tomahawk  Creek  a  third  ridge  appears,  which  bears 
northward  for  about  2  miles,  then  bends  toward  the  northeast  and  comes  to 
Big  Indian  Creek  about  2  miles  below  Earlville.  No  well-defined  continu- 
ation was  found  on  the  north  side  of  this  creek,  though  there  are  occasional 
knolls  along  the  divide  between  Big-  Indian  and  Little  Indian  creeks,  in 
both  Lasalle  and  Dekalb  counties,  which  may  mark  the  line  of  its  con- 
tinuation, and  which  would  connect  it  with  the  main  portion  of  this  morainic 
system  east  of  Shabbona.  The  ridges  whose  courses  have  just  been  out- 
lined have,  as  a  rule,  a  sharp  crest  as  well  as  swells  and  sags.  The  southern 
one  is  spoken  of  by  the  residents  as  the  "Backbone,"  since  it  is  quite  sharp, 
standing  in  places  60  to  80  feet  above  the  border  districts,  and  being 
scarcely  a  mile  in  width.  The  ridge  north  of  it  has  a  height  of  60  to  75 
feet  above  the  bordering  plain,  while  the  northernmost  ridge  has  a  height 
of  30  to  50  feet,  except  near  its  northern  terminus,  where  it  drops  down 
to  a  height  of  but  15  or  20  feet. 


262  THE  ILLINOIS  GLACIAL  LOBE. 

THICKNESS   OF   THE   DRIFT. 

The  tliickness  of  tlie  drift  in  the  Bloomington  morainic  system  is  prob- 
abl}^  about  equal  to  the  measure  of  the  relief  above  the  outer-border 
district,  which  has  a  maximum  of  nearly  200  feet  and  which  averages  75 
to  100  feet  along  the  ridges.  The  thickness  is  50  feet  or  less  between  the 
rido-es  and  on  plane  tracts  north  and  east  of  them.  Small  valleys  had  been 
formed  in  the  Shelbyville  sheet  prior  to  the  Bloomington  invasion,  and 
these  valleys  were  filled  with  the  drift  of  the  Bloomington  morainic  system. 
They  appear,  however,  to  have  been  usually  but  30  to  50  feet  or  less  in 
in  depth,  so  that  the  thickness  of  the  Bloomington  sheet  is  not  greatly 
increased  at  these  lines. 

The  di-ift  extends  to  some  depth  below  the  base  of  the  Bloomington 
drift  sheet.  It  is  found  that  the  earlier  sheets  of  the  Wisconsin  series  are 
present  in  considerable  strength,  as  well  as  the  lUinoian  drift.  The  lowan 
drift  is  present  in  northern  Illinois,  but  its  border,  as  already  noted,  passes 
under  the  Wisconsin  in  Bureau  County.  It  is  not  known  to  be  present 
beneath  the  Bloomington  system  south  from  Bureau  County,  unless  it  be 
on  the  inner  border  of  the  system  in  Iroquois  and  neighboring  counties. 
This  matter  is  discussed  above  in  connection  with  the  lowan  drift  sheet. 

In  determining  the  lower  limits  of  the  Wisconsin  drift,  two  conspicuous 
lines  of  evidence  are  drawn  upon.  One  is  an  abrupt  change  in  the  texture 
of  the  drift,  the  Wisconsin  di'ift  being  fresh  and  soft,  while  the  underlying 
sheets  are  harder  and  more  aged  in  appearance.  The  other  is  the  occur- 
rence of  a  black  soil,  beds  of  peat,  or  other  decisive  evidence  of  atmospheric 
action,  produced  at  the  surface  of  the  lower  or  buried  sheet  of  drift  prior  to 
the  deposition  of  the  later  drift.  In  the  portion  of  the  Wisconsin  drift 
lying  outside  the  hmits  of  the  lowan  it  is  often  an  easy  matter  to  decide  upon 
the  line  of  contact  between  the  Wisconsin  and  the  lUinoiau  by  the  change 
in  texture  alone.  It  is  so  marked  that  the  majority  of  well  drillers  have 
recoo-nized  the  two  sheets  even  where  no  soil  or  peat  has  been  preserved  at 
their  junction.  Where  the  two  lines  of  evidence  are  combined,  it  becomes 
an  easy  matter  to  decide  upon  the  line  of  contact.  It  is  not  so  easy  a 
matter  to  decide  upon  the  limits  of  the  Wisconsin  drift  where  it  is  underlain 
by  the  lowan,  for  the  contrast  in  texture  is  not  so  great  as  between  the 
Wiscorisin  and  Illinoian,  though  the  lowan  is  seldom  so  fresh  in  appearance 


THE  BLOOMIIs^GTON  MORAINIO  SYSTEM.  263 

as  the  Wisconsin,  even  where  deeply  buried  beneath  it.  There  are  numerous 
instances  of  the  occurrence  of  buried  soils  in  the  portion  of  Illinois  occupied 
by  both  the  lowan  and  the  Wisconsin  drift,  and  there  is  little  doubt  that 
such  soils  occur  below  each  drift,  but  seldom  are  two  soils  found  in  the 
same  exposure  or  well  section.  In  a  few  cases  the  soils  are  referred  with 
confidence  to  the  jimction  of  the  Wisconsin  and  lowan,  but  in  the  majority 
of  cases  they  appear  to  be  at  the  junction  of  the  lowan  and  Illinoian.  An 
inspection  of  the  well  records  presented  below  will  serve  to  make  clear  the 
difficulties  of  interpretation. 

These  well  records  indicate  that  buried  soils  differ  greatly  in  elevation 
within  short  distances  in  the  portion  of  Illinois  covered  both  by  the  lowan 
and  by  the  Wisconsin  di'ift.  This  difference  in  elevation  may  be  due  either 
to  the  presence  of  two  soil  horizons  or  to  an  erosion  of  a  buried  drift  sheet. 
In  the  latter  case  the  lower  soil  would  have  been  formed  in  a  valley,  while 
the  higher  would  have  been  formed  on  the  uplands.  Were  full  records  of 
wells  preserved,  it  might  be  possible  to  interpret  such  cases  satisfactorily. 
But  usually  the  imperfections  of  the  records  are  such  that  interpretations 
can  scarcely  be  made.  It  is  therefore  only  in  the  portion  of  the  Wisconsin 
drift  lying  outside  the  lowan  that  the  lower  limits  of  the  Wisconsin  are 
clearly  recognized.  It  is  highly  probable  that  the  Peorian  and  the  Sanga- 
mon soil  are  each  represented.  A  brief  statement  setting  forth  the  varia- 
tions in  elevation  of  the  buried  soils  in  each  of  the  counties  occupied  by 
the  Bloomington  morainic  system  will  serve  to  make  more  clear  the 
methods  of  interpretation  as  well  as  the  difficulties  of  correlation  in  portions 
of  the  district. 

In  Kane  County  buried  soils  appear  beneath  a  plain  southeast  of  Bur- 
lington at  a  depth  of  only  40  or  50  feet  and  at  an  elevation  of  about  850 
feet  above  tide.  The  soil  is  here  referred  with  some  confidence  to  the 
Peorian  interglacial  stage  at  the  base  of  the  Wisconsin  drift.  On  the 
elevated  moraine  southeast  from  this  plain  a  soil  is  found  at  a  depth  of 
180  to  200  feet  and  at  an  elevation  of  only  750  feet.  It  has  been  found  in 
several  wells  in  the  west  pai-t  of  T.  40,  R.  7  E.  This  lower  elevation  is 
probably  due  to  its  being  a  lower  soil  horizon,  presumably  the  Sangamon 
soil,  at  the  junction  of  the  lowan  and  Illinoian  sheets,  though  the  instances 
reported  may  chance  to  be  in  every  case  in  the  line  of  valleys  cut  in  the 
lowan.     The  wide  distribution,  however,  favors  the  interpretation  that  there 


264  THE  ILLINOIS  GLACIAL  LOBE. 

was  a  plain  at  about  this  level  prior  to  the  lowan  invasion.  In  the  neigh- 
boring township  on  the  south  buried  soils  are  reported  in  sees.  14,  15,  and 
20,  at  675,  710,  and  720  feet  above  tide,  which  are  probably  Sangamon.  In 
the  villaffe  of  Elbum  a  biu-ied  soil  occurs  at  790  feet  above  tide,  which 
is  perhaps  Peorian. 

In  Dekalb  County  only  a  few  instances  of.  buried  soil  were  collected. 
These  are  nearly  uniform  in  elevation  at  slightly  less  than  800  feet  above 
tide  and  are  slightly  lower  than  the  plain  outside  the  Wisconsin  drift.  It 
seems  probable  that  they  should  be  referred  to  the  Sangamon  soil,  at  the 
junction  of  the  lowan  and  Illinoian.  A  buried  soil  is  found  beneath  the 
lowan  di-ift,  outside  the  limits  of  the  Wisconsin,  in  the  A-icinity  of  Deer- 
field,  at  about  the  same  elevation. 

In  southeastern  Lee  County  soils  occur  at  a  level  lower  than  the  plain 
outside  the  Wisconsin  drift,  tlu-ee  instances  being  found  where  the  elevation 
is  720  to  740  feet,  while  the  plain  is  about  800  feet  above  tide.  These 
seem  referable  to  the  Sangamon  stage.  One  instance  was  found  in  sec.  34, 
T.  39,  R.  2  E ,  of  the  occiu-rence  of  a  buried  soil  at  about  the  elevation  of 
the  outer-border  plain;  this  may  be  referable  to  the  Peorian. 

In  northwestern  Lasalle  County  there  are  many  instances  of  the  occur- 
rence of  soil  at  600  to  650  feet.  This  low  elevation  would  suggest  its 
reference  to  the  junction  of  the  lowan  and  Illinoian  rather  than  the  base  of 
the  Wisconsin.  This  soil  horizon  is  well  preserved  in  eastern  Bureau 
County.  It  seems  to  be  quite  uniform  in  elevation  over  several  townships 
in  which  the  smface  of  the  Wisconsin  has  a  variation  of  more  than  100  feet 
in  altitude. 

In  the  counties  south  from  Bureau  County  the  lowan  di-ift  has  not 
been  recognized,  and  possiblj'  it  does  not  reach  these  counties.  No  records 
were  obtained  which  show  buried  soil  either  in  Putnam  or  in  Marshall 
County.  In  Woodford  County  wells  in  the  vicinity  of  Metamora  pass 
tlu'ough  a  soil  and  enter  a  hard  till  at  about  140  feet,  or  at  an  elevation  of 
680  feet  above  tide.  A  coal  shaft  at  I\Iinonk,  in  the  eastern  part  of  the 
county,  passes  from  soft  till  into  hard  till  at  about  the  same  elevation, 
though  the  depth  of  soft  till  there  is  only  62  feet.  It  is  probable  that  in 
both  of  these  instances  the  soil  is  referable  to  the  Sangamon.  In  northern 
Tazewell  County  exposm-es  were  found,  both  in  the  Illinois  blufi"  and  along 
Farm  Creek,  where  the  loess  occurs  beneath  the  Wisconsin  drift  at  an 


THE  BLOOMINGTON  MOEAINIO  SYSTEM.  265 

elevation  of  about  625  feet.  In  these  exposures  the  Peorian  and  Sangamon 
both  occur  as  noted  above.  Instances  of  buried  soil  at  an  elevation  of  625 
to  650  feet  are  r^Dorted  from  the  vicinity  of  Cooper,  which  are  probabl)^ 
Sangamon.  The  Wisconsin  drift  ranges  in  thickness  from  50  feet  up  to 
fully  150  feet  in  this  portion  of  Tazewell  County. 

In  northwestern  McLean  County  instances  of  a  bixried  soil  and  a  change 
from  soft  to  hard  till  are  found  at  a  depth  of  150  feet  beneath  the  crests  of 
morainic  ridg'es  and  at  an  elevation  of  650  feet  above  tide.  There  are 
instances  of  "black  clay"  at  lower  levels,  which  may  prove  to  be  soil  hori- 
zons. In  the  southwestern  part  of  the  county,  in  sec.  29,  T.  24,  R.  1  W., 
and  sec.  3,  T.  23,  R.  1  W.  (which  are  situated  south  of  the  Bloomington 
moraine),  the  fresh  till  extends  to  a  much  lower  elevation  than  in  neighbor- 
ing districts.  It  seems  probable,  therefore,  that  there  was  a  valley  or  con- 
cealed lowland  tract  traversing  these  sections.  In  sec.  3  a  black  muck  was 
found  below  the  fresh  till  at  a  depth  of  200  feet  and  at  an  elevation  of  but 
625  feet  above  tide.  In  the  vicinity  of  Bloomington  a  black  soil  is  found  at 
an  elevation  of  625  to  640  feet  above  tide,  which  probably  is  of  Sangamon 
age.  Another  buried  soil  occurs  near  the  base  of  the  drift  at  an  elevation  of 
about  540  feet.  This  is  beneath  a  hard  till  and  is  perhaps  preglacial.  North- 
eastward from  Bloomington  the  elevation  of  the  surface  of  tlae  Illinoian  drift 
sheet  is  found  to  soon  reach  700  feet;  at  least  wells  in  T.  24,  R.  4  E.  enter 
a  hard  till  at  that  elevation.  One  well  in  sec.  4  of  this  township  is  reported 
to  have  entered  hard  till  at  an  elevation  of  750  feet  above  tide.  South  from 
this  township,  in  the  vicinity  of  Leroy,  a  buried  soil  is  found  at  an  elevation 
of  740  feet  above  tide,  which  is  probably  under  the  Shelbyville  or  lowest 
Wisconsin  drift  sheet.  Eastward  the  elevation  of  the  surface  of  the  Illinoian 
drift  appears  to  decline  to  700  feet  or  less,  as  shown  by  wells  in  southern 
Livingston,  southwestern  Ford,  and  western  Champaign  counties.  The 
elevation  continues  decreasing  toward  the  north  and  east  across  northern 
Ford,  Iroquois,  and  Vermilion  counties.  The  elevation  of  the  Illinoian 
surface  throughout  much  of  Ii-oquois  County  and  northern  Vermilion 
County  is  600  feet  or  less. 

In  Iroquois  County,  as  noted  above,  there  are  two  soil  horizons,  one 
being  at  the  junction  of  the  fresh  and  soft  till  with  the  harder  till,  the  other 
being  in  the  midst  of  the  hard  till.  There  is  little  doubt  that  the  upper  soil 
marks  the  base  of  the  Wisconsin.     But  whether  the  sheet  of  drift  which  it 


266  THE  ILLINOIS  GLACIAL  LOBE. 

caps  is  lowan  or  Illinoian  lias  not  been  determined.     Upon  this  determina- 
tion must  rest  the  age  of  the  lower  soil  horizon. 

Buried  soils  are  exceptionally  well  preserved  along  much  of  the  course 
of  the  Bloomington  system  east  from  the  Illinois  River,  instances  of  their 
occiiiTence  in  well  sections  being  much  more  numerous  than  in  districts  to 
the  north,  except  limited  areas  in  Bureau,  Lasalle,  Kane,  and  McHenry 
counties.  There  is  scarcely  a  township  in  which  the  junction  of  the  "Wis- 
consin drift  with  older  sheets  may  not  be  satisfactorily  ascertained,  either 
through  the  presence  of  the  buried  soils  or  by  a  change  in  the  till. 

STRUOTUKE   OF   THE   DRIFT. 

Throughout  the  entire  length  of  the  Bloomington  system  the  great  mass 
of  the  drift  composing  its  moraines,  and  also  the  plains  between  them  and 
on  their  inner  borders,  together  with  earlier  sheets  of  the  Wisconsin  series, 
consists  of  a  soft  blue  till  moderately  stony  and  strikingly  in  contrast  with 
the  harder  till  found  beneath  it.  The  till  is  very  adhesive,  so  that  when 
excavated  by  a  well  auger  it  may  be  unrolled  in  great  masses.  The  under- 
lying harder  till  is  far  less  adhesive.  The  surface  portion  of  this  till  sheet 
is  oxidized  to  a  depth  of  6  to  10  feet  and  has  a  brownish  color.  There  are 
occasional  developments  of  a  pink-colored  till.  In  places  the  pink  color 
extends  to  gi'eat  depth,  but  usually  the  blue  color  sets  in  within  a  few  feet 
of  the  surface.  The  pink  color  is  especially  noticeable  in  the  western  and 
northern  part  of  the  morainic  system,  from  Peoria  County  northward. 
Yellow  till  is  also  reported  to  occur  in  the  midst  of  the  blue  till  at  many 
points.  It  apparently  marks  the  surface  of  earlier  sheets  of  the  Wisconsin 
series.  Its  occurrence  is  known  by  well  recoi'ds  only,  no  natural  exposures 
having  been  found.  Its  degree  of  leaching  and  its  state  of  oxidation  are 
not  known. 

Associated  with  the  till  at  various  depths  there  are  beds  of  sand  and 
gravel,  often  of  considerable  extent,  which  afford  a  supply  of  water  for  many 
wells.  It  is  not  usual,  however,  to  obtain  strong  wells  witliin  this  drift 
sheet.  In  every  county  hundreds  of  wells  have  been  sunk  to  lower  horizons 
because  of  the  inadequate  supply  found  in  this  sheet  of  drift. 

There  are  very  few  gravel  knolls  in  the  moraines  of  this  system,  though 
it  is  found  that  many  knolls  contain  gravelly  pockets  in  the  till  and  these 
have  been  utilized  to  some  extent  for  road  ballast.     The  amount  of  avail- 


THE  BLOOMINGTON  MOEAINIC  SYSTEM.  267 

able  gravel,  however,  seems  to  be  scarcely  adequate  to  supply  ballast  for  the 
wagon  roads  of  the  region  traversed  by  the  moraine.  The  composite  belt 
with  which  this  morainic  system  connects  at  the  northeast  is  much  better 
supplied  with  surface  gravel. 

As  noted  above,  the  outer  face  of  the  moraine  in  Lee  and  northern 
Bureau  counties  is  heavily  coated  with  sand,  which  apparently  has  been 
drifted  by  the  wind  from  the  Green  River  Basin  on  the  west.  From  this 
sand  belt  southward  through  central  Bureau  County  the  surface  of  the 
outer  ridge  is  in  j)laces  coated  with  sand  or  a  sandy  loam.  The  texture 
of  the  moraine  itself  is  also  exceptionally  sandy  in  that  portion  of  the  belt. 
Sand  is  found  in  the  form  of  dunes  along  the  east  bluff  of  the  Illinois 
River,  from  the  bend  of  the  river  at  Hennepin  southward  to  the  inner  border 
of  this  morainic  system.  Sand  deposits  were  also  noted  on  the  inner  slope 
of  the  moraine  in  northern  Vermilion  County  and  west  from  the  reentrant 
angle  in  southeastern  Livingston  County.  It  is  probable  that  the  sand 
deposits  in  both  these  localities  are  attributable  to  the  presence  of  temporary 
glacial  lakes  held  in  front  of  the  retreating-  ice  sheet,  whose  waves  worked 
upon  the  surface  of  the  till  sheet  and  formed  the  sandy  beds  there  present. 
As  noted  below,  sand  in  places  assumes  the  cliaracteristic  features  of  beaches 
or  shore  lines  in  portions  of  the  plains  noi'th  of  this  morainic  system. 

The  surface  of  this  morainic  system  from  the  vicinity  of  Bloomington 
northward  to  Dekalb  County  is  generally  coated  with  a  loess-like  loam  or 
silt  to  a  depth  of  2  to  4  feet.  East  from  Bloomington  this  surface  silt  is  so 
thin  as  scarcely  to  conceal  surface  bowlders.  The  silt  also  extends  over 
the  plain  east  of  this  morainic  system  in  counties  bordering  the  Illinois 
River,  and  has  often  a  depth  of  6  or  8  feet  on  these  plains.  It  is  especially 
prominent  on  the  plain  between  the  outer  and  inner  belts  in  the  Bureau 
Creek  Basin,  its  average  thickness  being  not  less  than  6  feet.  From  the 
inner  belt  eastward,  in  Bureau  and  Lasalle  counties,  it  is  less  conspicuous 
than  in  the  Bureau  Creek  Basin,  being  scarcely  2  feet  in  average  thickness. 

This  surface  silt  was  apparently  deposited  within  a  short  time  after  the 
retreat  of  the  ice  sheet,  for  the  underlying  till  sheet  appears  to  have  suffered 
no  leaching  prior  to  its  deposition.  The  origin  and  mode  of  deposition  of 
this  silt  or  loess-like  loam,  like  that  on  adjacent  portions  of  the  Shelbyville 
sheet,  are  as  yet  not  clearly  inaderstood.  The  loess-covered  plains  on  the 
west  seem  to  afford  a  source  of  supply,  and  the  prevailing  winds,  if  in  the 


268  THE  ILLINOIS  GLACIAL  LOBE. 

same  direction  as  now,  would  have  earned  miicli  atmospheric  dust  from 
them  eastward.  Tt  is  quite  probable  that  some  of  the  material  was  derived 
from  this  source,  though  perhaps  only  a  minor  part.  It  is  found  that  this 
loess  loam,  when  reaching  a  depth  of  4  to  6  feet  or  more,  is  usually  highly 
calcareous  in  its  lower  portion,  while  the  loess  of  the  outer-border  districts 
is  thoroughly  leached  to  a  depth  of  several  feet.  In  all  probability  it  had 
suffered  considerable  leaching  before  the  ice  sheet  withdrew  from  the 
Bloomington  morainic  system.  It  is  to  be  expected,  therefore,  that  a  non- 
calcareous  or  leached  deposit  would  be  made  by  transportation  of  dust 
from  these  plains.  '  The  presence  of  the  calcareous  material  in  the  silt 
which  caps  the  western  border  of  the  -Blooixdngton  till  sheet  seems  to  make 
it  necessary  to  call  in  the  action  of  glacial  waters  charged  with  fresh  cal- 
careous silt.  The  manner  in  which  the  silt  was  distributed  is  an  unsettled 
question  and  one  on  which  further  light  seems  necessary.  It  will  probably 
be  found  in  a  combination  of  aqueous  and  seolian  agencies.  As  shown 
below,  the  drainage  conditions  on  the  outer  border  of  the  Bloomington 
system  were  favorable  for  the  transportation  of  gravel  by  streams  issuing 
from  the  ice  margin.  There  would  appear,  therefore,  to  have  been  a  rapid 
descent  for  these  streams  to  the  region  south  and  west  from  the  ice  sheet. 
Such  being  the  case,  we  can  scarcely  infer  that  the  loess  which  covers  the 
elevated  parts  of  the  morainic  system  was  deposited  by  a  sheet  of  water, 
for  this  would  imply  a  general  submergence.  It  is  suggested  that  there 
may  have  been  portions  of  the  border  district  in  which  the  waters  found 
inadequate  di'ainag'e.  In  such  places  silts  may  have  been  spread  out  which 
were  afterwards  transported  by  wind  to  the  moraine.  The  matter,  however, 
is  one  of  conjecture  rather  than  of  demonstration. 

Surface  bowlders  are  numerous  only  at  a  few  points  on  this  morainic 
system,  being  rarely  met  where  no  sand  or  silt  deposits  are  present  to 
conceal  them.  But  in  this  respect  the  Bloomington  system  is  not  different 
from  other  moraines  of  the  early  Wisconsin  series.  In  Kane,  Dekalb, 
and  Ogle  counties  there  are  occasional  bowlders  along  the  crests  of  the 
ridges,  but  they  seldom  become  conspicuous.  On  the  plane  tracts  in  these 
counties  they  are  quite  rare,  but  this  is  not  a  fair  field  for  study  because 
there  is  us-ually  a  sufficient  amount  of  silt  to  conceal  them.  Bowlders 
abound  along  the  outer  face  of  the  outer  belt  for  a  few  miles  in  south- 
eastern Lee  County  and  on  the  crest  and  outer  face  at  a  few  i)oints  in 


THE  BLOOMINGTON  MOEAINIC  SYSTEM.  269 

Bureau,  Marshall,  and  Peoria  counties,  there  being  some  farms  on  which 
they  are  a  serious  hindrance  to  the  cultivation  of  the  soil.  But  much  of 
the  moraine  in  these  counties  is  silt  or  sand  covered  to  a  depth  of  several 
feet,  so  that  bowlders,  if  j)resent,  are  concealed.  In  the  portion  of  the 
morainic  system  between  the  Illinois  River  and  Bloomington  scarcely  any 
surface  bowlders  were  noted,  though  there  the  surface  silts  are  several 
feet  in  depth.  From  Bloomington  eastward  there  is  generally  a  sufficient 
number  of  bowlders  at  surface  or  at  slight  depth  in  the  soil  to  meet 
demands  for  some  time  to  come  in  supplying  foundations  for  buildings. 
In  places  they  were  so  numerous  that  farmers  have  collected  them  in  piles 
in  the  fields.  Such  is  the  case  in  the  northern  tier  of  townships  of  Vermil- 
ion County,  both  along  the  crest  of  the  north  ridge  and  on  its  inner  slope. 
The  bowlders  range  in  size  from  8  or  10  feet  in  diameter  downward,  the 
ordinary  size  being  2  to  4  feet.  Granite  bowlders  predominate  over  other 
classes  of  rock  along  nearly  the  entire  belt,  and  a  few  limestones  were 
noted.  Greenstones  and  quartzites  are  also  common.  The  bowlders  are 
in  some  cases  much  rounded  by  exfoliation,  a  feature  which  seems  more 
conspicuous  than  in  bowlders  on  the  Shelbyville  sheet.  Numerous  com- 
parisons were  made  of  bowlders  embedded  in  the  till  with  those  found  at 
the  surface,  and  in  almost  every  instance  it  was  found  that  local  or  semi- 
local  rocks  are  much  more  abundant  in  the  till  than  among  the  surface 
bowlders.  A  much  larger  proportion  of  striated  stones  is  also  found  in  the 
till  than  at  the  sm-face ;  indeed,  the  surface  bowlders  are  seldom  striated. 
These  are  features  which,  as  already  noted,  are  generally  characteristic  of 
the  till  of  the  entire  region  under  discussion  in  each  of  the  several  sheets 
represented.  Occasionally  very  large  limestone  blocks  are  foinid  at  the 
surface  or  but  shghtly  embedded  in  the  drift.  One  block  found  a  short 
distance  northwest  of  Rossville,  in  Vermilion  County,  furnished  several 
wagon  loads  of  excellent  building  stone,  and  when  first  discovered  was 
thought  to  be  a  ledge  in  situ,  but  subsequently  proved  to  be  a  bowlder 
embedded  in  the  till.  In  that  vicinity  the  drift  is  about  200  feet  in  depth 
and  is  underlain  by  the  Coal  Measures.  The  nearest  known  outcrop  of 
limestone  is  about  30  miles  to  the  north. 

Numerous  well  sections  collected  along  the  line  of  this  morainic  system 
are  presented  in  the  discussion  of  the  wells  in  the  latter  part  of  this  report, 
and  these  will  serve  to  illustrate  the  variations  in  structure  which  this 
morainic  system  presents. 


270  THE  ILLINOIS  GLACIAL  LOBE. 

CHARACTER  OF  THE  OUTWASH. 

The  writer's  examination  of  the  features  on  the  outer  border  of  the 
Bloomington  morainic  system  covers  the  portion  from  Bloomington  north- 
ward, and  the  discussion  pertains  chiefly  to  that  portion.  The  portion  east- 
ward from  Bloomington  was  examined  some  years  since  by  Prof.  R.  D. 
Sahsbm-}',  but  has  received  scarcely  any  attention  from  the  writer. 

It  will  be  obser-^-ed  that  the  Bloomington  morainic  system  forms  the 
source  of  several  streams  whose  courses  are  southward  or  westward  from  it 
through  the  outer-border  district.  It  also  forms  the  source  of  other  streams 
which  lead  northward  or  eastward  or  southeastward  through  the  inner- 
border  district.  Still  other  streams  flow  through  this  morainic  system  from 
the  inner  into  the  outer  border  district.  Of  the  first  class  the  several  head- 
water forks  of  Wabash- Vermilion  River,  Sangamon  River,  Salt  Creek,  the 
two  Kickapoo  creeks.  Sugar  Creek,  Green  River,  and  the  two  forks  of  Kish- 
waukee  River  are  worthy  of  mention.  Of  the  second  class,  Iroquois  River, 
the  Illinois-Vermilion  RiA'er,  Bureau  Creek,  and  the  western  tributaries  of 
Fox  River  are  illustrations.  Of  the  third  class  the  Illinois  and  Mackinaw 
rivers  are  the  only  examples  in  Illinois. 

An  examination  of  these  valleys  brings  to  light  important  contrasts. 
The  streams  which  flow  away  from  the  outer  border  of  the  moraine  are  in 
most  instances  found  to  occupy  valleys  which  had  been  excavated  somewhat 
by  streams  which  antedated  the  formation  of  this  moraine.  These  valleys 
received  the  outwash  from  the  moraine  and  were  partially  filled  by  it.  The 
streams  on  the  inner  border  of  the  moraine  had  not  the  advantage  of 
previously  formed  valleys,  and  in  consequence  their  channels  are  entirely 
the  result  of  stream  action  since  the  withdrawal  of  the  ice  sheet  from  this 
morainic  system.  It  is  found  that  the  valleys  which  lead  away  from  the 
moraine  through  the  outer-border  district  have  in  most  instances  a  filling  of 
gravel  or  sand  which  is  definitely  connected  with  the  morainic  system  as  an 
outwash  from  the  ice  sheet.  The  streams  which  lead  from  the  moraine 
across  the  innei'-border  district  are  not  thus  characterized  by  sand-and- 
gravel  filling.  In  some  cases  the  streams  issuing  from  the  edge  of  the  ice 
sheet  had  sufiicient  force  to  transpoi't  gravel  for  many  nnles  away  from  the 
ice  border.  In  other  instances  they  were  able  to  carry  the  gravel  but  a  few 
miles,  as  shown  in  the  discussion  below.     The  extent  of  the  gravelly  and 


THE  BLOOMINGTOiSr  MORAimO  SYSTEM.  271 

sandy  outwasli  along-  the  borders  of  the  Bloomington  morainic  system  is 
outhned  in  the  glacial  map,  PI.  VI,  where  it  may  be  compared  with  that  of 
other  morainic  systems.  This  comparison  shows  that  the  outwash  was  fully 
as  extensive  as  in  any  substage  of  the  early  or  late  Wisconsin.  It  is,  how- 
ever, of  a  finer  grade  than  in  some  of  the  later  snbstages,  a  feature  which 
seems  to  indicate  that  the  attitude  of  the  land  may  have  been  scarcely  so 
favorable  for  vigorous  di-ainage  as  in  the  later  substages.  In  the  following 
detailed  discussion  the  valleys  in  the  vicinity  of  Bloomington  are  first  con- 
sidered. From  this  point  the  valleys  are  taken  up  in  order  toward  the  west 
and  north,  along  the  outer  border  of  the  morainic  system. 

For  a  few  miles  southeast  from  the  meridian  of  Bloomington  there  is  a 
shallow,  valley-like  depression  along  the  outer  border  of  the  moraine.  It 
is  about  a  half  mile  in  width,  and  its  surface  stands  15  to  25  feet  below  the 
plain  on  the  south  and  75  or  100  feet  below  the  crest  of  the  moraine  on 
the  north.  Its  eastern  end  is  near  the  village  of  Downs,  at  Kickapoo  Creek. 
It  leads  westward  across  the  interval  between  East  and  West  Kickapoo 
creeks,  and  also  across  that  between  West  Kickapoo  Creek  and  an  eastern 
tributary  of  Sugar  Creek.  Both  branches  of  Kickapoo  Creek  pass  directly 
across  it,  but  the  branch  of  Sugar  Creek  referred  to  follows  the  depression 
westward  for  a  distance  of  2  miles,  and  there  turns  away  from  the  moraine. 
The  depression  is  found  to  have  a  filling  of  fine  gravel  and  sand  of  con- 
siderable depth,  so  that  wells  10  or  20  feet  deep  do  not  reach  its  bottom. 
The  gravel  was  carried  from  this  valley-like  depression  for  some  distance 
down  each  of  the  valleys  which  lead  away  from  it,  and  is  preserved  in  the 
form  of  terraces  which  stand  20  or  30  feet  below  the  level  of  the  bordering 
plains  and  about  20  feet  above  the  present  stream  bed.  The  gravel  prob- 
ably extends  down  at  least  to  the  level  of  the  present  streams.  It  would 
appear,  therefore,  that  valleys  had  been  excavated  to,  if  not  beyond,  their 
present  depth  prior  to  this  filling.  The  gravel  filling  was  traced  down 
Kickapoo  Creek  beyond  Hey  worth,  a  distance  of  about  10  miles  fi'om 
the  outer  border  of  the  moraine.  Just  north  of  Heyworth  it  is  preserved 
in  a  broad  terrace  which  has  been  extensively  opened  for  gravel  by  the 
Illinois  Central  Railway.  How  much  farther  down  the  valley  the  gravel 
was  transported  has  not  been  determined.  On  the  tributary  of  Sugar 
Creek  which  leads  away  from  the  western  end  of  this  depression  the  gravel 
deposits  were  followed  continuously  down  to  a  point  east  of  Shirley.     They 


272  THE  ILLINOIS  GLACIAL  LOBE. 

were  also  noted  at  Funk's  Grrove  and  at  points  below.  The  gravel  was 
apparently  transported  to  the  junction  of  this  fork  with  a  more  western 
tributary.  In  each  of  these  valleys  the  gravel  is  of  medium  coarseness 
and  carries  a  moderate  admixture  of  sand.  The  presence  of  the  sand  is 
thought  to  indicate  that  the  current  was  not  vigorous,  though  it  may  have 
been  somewhat  stronger  than  that  of  the  present  stream,  for  the  latter  finds 
it  difficult  to  transport  the  coarser  portions  of  the  material  even  at  flood 
stages.  As  these  valleys  are  narrow,  averaging  scarcely  more  than  one- 
fourth  mile  and  seldom  reaching  one-half  mile  in  width,  the  glacial  streams 
which  occupied  them  can  not  have  had  very  great  volume.  The  depression 
on  the  outer  border  of  the  moraine  does  not  seem  to  fit  in  naturally  as  a 
part  of  the  drainag-e  which  preceded  the  formation  of  the  morainic  system. 
As  yet,  no  satisfactor}^  explanation  of  its  mode  of  formation  has  been  found. 
Possibly  it  was  formed  in  connection,  with  the  ice  invasion,  either  by  the 
ice  or  by  waters  issuing  from  it.  It  bears  some  resemblance  to  "The 
Fosse"  on  Nantucket  Island  described  recently  by  Curtis  and  Woodworth 
in  the  Journal  of  Greology,  though  it  has  not  a  sand  plain  or  overwash 
apron  on  its  south  border.^ 

On  the  branch  of  Sugar  Creek  which  leads  through  the  west  part  of 
Bloomington  there  is  a  belt  of  gravel  60  to  120  rods  in  width,  which 
extends  up  the  valley  at  least  to  the  Bloomington  waterworks  in  sec.  32, 
Normal  Township,  just  outside  the  inner  large  ridge  of  the  Bloomington 
morainic  system.  At  its  head  it  is  merged  with  the  flood  plain  of  the  creek, 
but  from  Bloomington  southw:ard  it  stands  a  few  feet  above  the  flood  plain. 
The  depth  of  gravel  at  the  waterworks  is  about  30  feet,  and  it  appears  to 
maintain  this  depth  for  some  distance  below  Bloomington.  There  is  usually 
a  yellow-brown  silt  4  to  6  feet  in  depth  capping  the  gravel.  The  gravel 
contains  a  large  amount  of  fine  material,  so  that  sand  is  screened  from  it 
for  plasterers'  use.  Large  pebbles  are  rare,  though'  it  contains  a  few  5  or  6 
inches  in  diameter.  This  branch  of  Sugar  Creek  reaches  the  outer  border 
of  the  Bloomington  morainic  system  about  5  miles  below  the  waterworks. 
The  gravel  here  spreads  westward  beyond  the  limits  of  the  valley,  covering 
the  lower  portions  of  the  plain  between  this  branch  of  Sugar  Creek  and 
one  that  leaves  the  moraine  4  miles  to  the  west.     Low  till  swells  lise  above 

'Nantucket  a  morainal  island:  By  6.  C.  Curtis  and  J.  B,  Woodworth,  Jour.  Geol.,  Vol.  VII, 
1899,  pp.  226-236,  PI.  I,  Figs.  1-5. 


THE  BLOOMINGTON  MORAINIC  SYSTEM.  273 

the  level  of  the  gravel  surface,  showing-  that  the  deposit  is  thin.  The 
western  tributary  also  has  gravelly  deposits  above  tlie  point  of  its  emergence 
from  the  moraine,  but  these  were  not  traced  to  their  head.  The  distance  to 
which  the  gravel  deposits  have  been  carried  down  the  two  branches  of 
.  Sugar  Creek  beyond  the  border  of  the  moraine  is  not  ascertained,  but  it  is 
known  to  be  at  least  10  miles. 

Mackinaw  River  has  its  source  on  the  inner  border  of  the  main  ridges 
of  the  Bloomington  system,  but  Cropsey  Ridge,  one  of  the  weaker  mem- 
bers of  the  system,  lies  north  of  the  headwater  poi'tion  of  the  stream. 
Gravelly  deposits  have  been  noted  at  a  few  points  on  the  borders  of  the 
headwater  portion.  They  have  not,  however,  been  traced  into  definite 
connection  with  Cropsey  Ridge.  There  is  not  a  continuous  belt  of  gi-avel 
leading  down  the  valley  from  this  headwater  portion.  A  section  several 
miles  in  length  was  examined  just  below  the  crossing  of  the  Lake  Erie 
and  Westei'n  Railway,  in  which  no  gravel  filling  appears  to  have  been 
made.  That  portion  of  the  valley  was  found  to  contain  deposits  of  silt 
of  considerable  thickness  which  reach  a  level  20  or  30  feet  above  the 
present  stream.  Upon  continuing  down  the  valley  to  the  inner  border  of 
the  outer  morainic  ridge  a  gravel  terrace  is  found  to  set  in  abruptly  at  an 
altitude  about  50  feet  above  the  stream.  This  terrace  merges  into  low 
gravelly  knolls  at  its  head  and  on  its  border,  and  thus  makes  a  definite  con- 
nection with  the  moraine.  As  it  stands  somewhat  higher  than  the  silt-filled 
portion  of  the  valley  just  above  its  head,  there  was  probably  a  pool  in  that 
portion  of  the  valley  prior  to  the  excavation  of  the  gravel  which  forms  the 
moraine-headed  terrace,  and  the  silt  deposits  just  noted  were  probably  laid 
down  in  this  pool. 

Mackinaw  Valley  appears  to  have  been  excavated  nearly  to  the  level 
of  the  present  stream  prior  to  the  formation  of  the  Bloomington  system  and 
to  have  had  a  width  of  nearly  a  mile.  The  terrace  has  been  traced  down 
the  valley  continuously  from  the  moraine  to.  the  point  where  the  Mackinaw 
enters  the  Illinois  Valley  in  the  eastern  part  of  Sand  Prairie  Township,  a 
distance  by  direct  line  of  about  17  miles  from  the  outer  border  of  the 
moraine.  The  altitude  of  the  ten-ace  decreases  about  100  feet  in  this  dis- 
tance, being  640  feet  at  the  outer  border  of  the  moraine  and  650  feet  at  the 
point  where  it  joins  the  Illinois  Valley.     The  stream  falls  83  feet  in  the 

MON  XXXVIII 18 


274  THE  ILLINOIS  GLACIAL  LOBE. 

same  distance  (from  573  to  490  feet),  and  the  teiTace  maintains  a  somewhat 
regular  altitude  above  it,  being  about  65  or  70  feet  above  it  at  the  outer 
border  of  the  moraine  and  50  feet  at  the  border  of  the  Illinois  Valle}'.  The 
terrace  apparently  has  little  fall  in  the  3  or  4  miles  occupied  in  crossing  the 
moraine.  The  remnants  of  the  tex'race  occupy  nearly  one-third  of  the 
width  of  the  A^alley.  Several  good  exposures  of  the  gravel  were  found,  and 
these  quite  uniformly  show  a  coarse  gravel  and  cobble  near  the  surface  of 
the  terrace,  with  finer  gravel  below.  The  coarseness  of  the  material  is  such 
as  to  indicate  vigorous  drainage,  apparently  stronger  than  that  of  the 
present  stream. 

A  small  northern  tributary  of  the  Mackinaw,  Deer  Creek,  emerges 
from  the  moraine  a  few  miles  north  from  the  point  where  the  Mackinaw 
leaves  it.  This  also  carries  deposits  of  gravel  along  the  borders  of  the 
valley.  It  is  preserved  in  small  remnants  flanking  the  slopes  up  a  height 
of  20  or  25  feet  above  the  creek  at  the  point  where  the  stream  leaves  the 
moraine.  The  upland  plain  stands  about  20  feet  higher  than  the  upper 
limits  of  the  gravel. 

On  Farm  Creek,  a  tributary  of  the  Illinois,  entering  opposite  Peoria, 
there  is  a  gravel  deposit  heading  in  the  midst  of  the  Bloomington  system 
about  2  miles  west  of  Washington.  This  has  been  traced  continuously 
down  to  the  Illinois  River  Valley,  a  distance  of  8  miles.  At  its  head  it  is 
nearly  as  low  as  the  creek  flood  plain,  being  scarcely  10  feet  above  the 
stream,  but  its  fall  is  far  less  rapid  than  that  of  the  creek.  The  creek  has 
a  fall  of  about  180  feet  in  the  8  miles  while  the  terrace  falls  scarcely  60 
feet.  At  Farmdale  the  terrace  stands  about  85  feet  above  the  creek  and  at 
East  Peoria  about  120  feet.  The  depth  of  the  gravel  on  tliis  terrace  is 
usually  only  15  or  20  feet,  including  a  silt  capping  3  or  4  feet  in  depth. 
The  bi-eadth  of  the  valley  in  which  it  is  deposited  was  apparently  one- 
eighth  to  one-fourth  of  a  mile.  The  present  stream  has  in  places  formed  a 
valley  of  greater  width,  but  usually  it  is  confined  to  narrower  limits  than 
the  old  valley.  The  valley  in  which  the  gravel  filling  was  made  had  been 
nowhere  cut  to  a  depth  of  more  than  40  or  50  feet  below  the  bordering 
plain  outside  the  Bloomington  moraine,  and  the  gravel  filling  has  reduced 
this  depth  to  about  25  feet.  The  work  performed,  by  the  stream  which 
preceded  the  gravel  filling  was  tlierefore  but  a  small  fraction  of  the  amount 
performed  by  Farm  Creek  since  tluit  filling. 


5  Q      _ 


O  tr 

Li-    O 


THE  BLOOMIXGTOJS  MOEAIMC  SYSTEM.  275 

On  the  Illinois  River  Valley  there  ai'e  extensive  gravel  deposits  forming- 
a  broad  terrace  which  occupies  a  gap  in  the  Shelby ville  moraine  just  below 
the  outer  border  of  the  Bloomington  moraine,  a  gap  through  which  the 
river  passes.  The  north  part  of  the  city  of  Peoria  stands  on  this  terrace 
and  is  commonly  referred  to  as  the  bluff  or  upland  portion,  since  it  stands 
about  170  feet  above  the  Illinois  River.  These  deposits  may  prove  to  date 
from  the  Shelbyville  substage  of  glaciation,  though  from  their  coarseness 
and  general  relations  it  seems  more  probable  that  they  were  connected  with 
the  Bloomington  and  represent  the  height  of  valley  filling  on  the  outer 
border  of  that  morainic  system.  Their  freshness  cei'tainly  places  them  in 
the  Wisconsin  series.  The  following  reasons  for  referring  them  to  the 
Bloomington  rather  than  the  Shelbyville  substage  may  be  mentioned: 
(1)  The  terrace  corresponds  closely  in  elevation  with  the  gravel  terrace 
on  Farm  Creek  just  described,  which  connects  with  the  Bloomington 
morainic  system  east  of  the  Illinois  River;  (2)  the  terrace  on  the  Illinois 
occupies  a  shallow  valley  cut  into  the  Shelbyville  till  sheet ;  (3)  the  vigor  of 
drainage  corresponds  to  that  of  the  Bloomington  and  is  greater  than  seems 
elsewhere  to  characterize  the  Shelbyville  substage  of  glaciation.  A  view 
in  a  gravel  pit  on  this  terrace  appears  in  PL  XIII.  The  gravel  wherever 
exposed  on  this  terrace  is  composed  largely  of  limestone  pebbles.  The 
local  sandstone  and  shale  pebbles  and  the  Canadian  crystallines  constitute 
only  a  small  percentage  of  the  coarse  rock  material.  The  sand  and  fine 
material  found  associated  with  the  gravel  are  also  calcareous.  In  places 
the  gravel  is  cemented  with  lime.  It  is  probable  that  the  large  percentage 
of  limestone  pebbles  is  due  to  the  great  number  of  such  jjebbles  in  the  till 
of  the  Wisconsin  sheet  in  that  vicinity. 

The  highest  well-defined  terrace  noted  on  the  Illinois  above  Peoria, 
which  seems  referable  to  the  Bloomington  substage  of  glaciation,  is  found 
near  the  inner  border  of  the  moraine  at  and  below  the  village  of  Chillicothe. 
It  stands  only  550  to  560  feet  above  tide,  or  40  to  50  feet  lower  than  the 
terrace  on  the  outer  border  at  Peoria.  This  difference  is  probably  referable 
in  part,  if  not  entirely,  to  a  reduction  from  the  original  height  of  valley 
filling,  for  a  well-defined  bank  separates  the  top  of  the  terrace  from  the 
portions  of  the  moraine  bordering  it.  The  terrace  in  the  vicinity  of  Chilli- 
cothe contains  much  coarser  material  than  at  points  above  or  below.  The 
extensive  excavations  for   railway  ballast   reveal   a   mass   of  cobble   and 


276  THE  ILLINOIS  GLACIAL  LOBE. 

bowlders  20  or  30  feet  in  depth.  The  excessive  amount  of  coarse  material 
seems  referable  to  the  contribution  of  such  material  from  the  overhanoino: 
ice  during  the  building-  up  of  the  teiTace.  For  this  reason  the  terrace  has 
been  connected  with  the  Bloomington  rather  than  a  later  substage.  Possibly 
some  cutting  of  the  valley  of  the  Illinois  took  place  between  the  heavv 
deposition  of  gravel  on  the  outer  border  and  that  near  the  inner  border  of 
the  moraine,  in  which  case  the  deposits  near  the  inner  border  raaj  not  have 
been  built  up  to  the  level  of  those  on  the  outer  border.  This  view  seems 
supported  by  the  observations  farther  up  the  valley,  no  remnants  higher 
than  that  at  Chillicothe  ha^dng  been  found. 

Down  the  valle}^  from  Peoria  there  is  a  rapid  decrease  in  the  altitude  of 
the  gravel  terrace,  a  fall  of  70  or  80  feet  being  made  in  the  10  miles  to  the 
mouth  of  the  Mackinaw  River,  just  below  Pekin.  There  is  a  great  expansion 
of  the  valley  just  below  that  city,  in  which  the  gravel  has  an  elevation  of  520 
to  530  feet  above  tide,  or  90  to  100  feet  above  the  Illinois  River.  The  gravel 
is  capped  by  sandy  deposits,  which  are  in  places  drifted  into  dunes  20  to 
30  feet  or  more  in  height.  Gravel  deposits  are  conspicuous  down  the  val- 
ley beyond  the  mouth  of  the  Sangamon  River,  but  the  material  becomes 
finer  in  passing  down  the  stream.  The  gi'avel  has  a  height  of  about  500 
feet  above  tide  at  the  ro^outh  of  the  Sangamon,  or  75  to  80  feet  above  the 
level  of  the  Illinois  River.  Farther  down  it  gradually  approaches  the 
level  of  the  river,  tlie  highest  terraces  near  the  mouth  of  the  sti'eam,  which 
seem  connected  with  the  Wisconsin  invasion,  being  but  40  to  50  feet  above 
low  water. 

There  appears  to  have  been  no  gravel  outwash  into  Kickapoo  Creek 
Valley  in  northern  Peoria  County,  although  this  stream  follows  the  outer 
border  of  the  moraine  quite  closely  for  a  distance  of  7  or  8  miles.  Upon 
turning  away  from  tlie  moraine  the  creek  cuts  through  the  Shelb5'ville 
moraine,  and  it  is  proba]:)le  that  this  offered  an  obstruction  to  the  rapid 
escape  of  waters  from  the  ice  margin. 

In  southeastern  Stark  County  there  is  a  low  plain  extending  back  from 
Spoon  River  Valley  to  the  Bloomington  moraine  which  received  a  slight 
outwash  from  the  moraine.  A  few  exposures  were  found  where  gravel  to  a 
depth  of  several  feet  was  deposited.  It  seems,  however,  to  have  been  only 
a  weak  point  of  discharge,  as  the  gravel  deposits  scarcel3'  extend  to  Spoon 
River  Vnll('\-,   tliougli  this  valley  apjiroaches  within  6   or  7   miles  of  the 


THE  BLOOMINGTON^  MORAINIC  SYSTEM.  277 

moraine  and  receives  two  tributaries  which  head  in  the  moraine.  There 
are  other  tributaries  of  Spoon  River  farther  north  which  also  head  in  the 
moraine,  but  these  seem  to  have  afforded  only  weak  lines  of  escape  for 
glacial  waters. 

The  portion  of  the  moraine  bordering  the  Green  River  Basin  in  north- 
ern Biireau  and  southeastern  Lee  counties,  as  already  noted,  is  coated 
heavily  with  sand  on  its  outer  face.  The  sand  extends  westward  from  the 
moraine  down  the  Green  River  Valley,  covering  southeastern  Whiteside 
and  northern  Henry  counties  and  occupying  the  low  tract  between  Green 
and  Rock  rivers.  This  sand  is  in  all  probability  an  outwash  from  the 
moraine,  being  too  extensive  a  deposit  to  be  referable  to  the  action  of  lake 
waves.  The  sand  apparently  forms,  over  much  of  the  district  which  it 
occupies,  a  coating  10  to  20  feet  or  more  in  depth.  The  depth  is  so  great 
that  natural  exposures  of  underlying  beds  are  rare  and  only  a  few  wells 
reach  its  bottom.  It  is  therefore  difficult  to  ascertain  whether  there  is 
much  gravel  outwash.  Near  the  border  of  the  moraine  in  northern  Bureau 
County  there  are,  however,  a  few  exposures  of  gravel  at  the  base  of  the 
sand  which  are  thought  to  be  an  outwash  from  the  moraine.  The  gravel 
appears  to  extend  but  a  few  miles  west,  for  in  the  vicinity  of  the  county 
line  of  Btireau  and  Hemy  counties  wells  indicate  that  the  sand  rests  upon 
a  compact  clay. 

At  the  head  of  the  Green  River  Basin,  in  eastern  Lee  County,  there  is 
a  gravel  plain,  covering  about  25  square  miles,  whose  eastern  border  is  in 
the  moraine.  It  extends  back  into  the  moraine  a  mile  or  more,  along  the 
east  and  south  branches  of  Willow  Creek,  and  there  coimects  with  gravelly 
knolls  which  dot  the  valley  slopes  and  bottoms  for  2  or  3  miles  farther  east. 
This  gravel  plain  extends  northward  along  the  west  border  of  the  moraine 
to  the  south  branch  of  Kite  River  at  Steward.  At  this  stream  also  the  g'ravel 
plain  connects  closely  with  gravelly  knolls  which  extend  some  distance  up 
the  valley  into  the  moraine.  The  gravel  extends  only  a  few  miles  away 
from  the  moraine,  scarcely  beyond  the  east  border  of  Inlet  Swamp.  The 
waters  issuing  from  the  ice  sheet  probably  had  sufficient  strength  to  carry 
the  gravel  down  the  rapid  slope  to  Inlet  Swamp,  beyond  which  they  could 
carry  only  sand.  There  is  considerable  fall  in  the  Green  River  Basin,  but 
it  is  irregularly  distributed,  so  that  di-ainage  even  now  is  very  imperfect. 


278  THE  ILLINOIS  GLACIAL  LOBE. 

On  the  outer  border  of  the  moraine  in  eastern  Ogle  County  there  is  a 
depression  due  to  a  preglacial  valley  which  was  not  completely  filled.  Into 
this  depression  considerable  sand  and  fine  gravel  was  carried  by  the  waters 
issuing-  from  this  moraine.  There  were  two  lines  of  escape,  the  southern 
portion  of  the  depression  being  drained  westward  through  Kite  River,  while 
the  northern  portion  was  drained  northward  through  Killbuck  Creek.  The 
sandy  and  gravelly  deposits  are  thickest  along  the  portion  drained  by  Kill- 
buck  Creek,  where  they  have  a  depth  of  20  feet  or  more.  In  the  portion 
di-ained  by  Kite  River  the  average  depth  is  but  5  or  10  feet,  and  portions 
of  the  depressed  area  have  scarcely  any  surface  gravel.  The  deposits  in 
this  depressed  tract  would  be  classed  as  a  gravelly  sand  rather  than  gravel, 
the  proportion  of  coarse  material  being  very  small.  The  streams  issuing 
from  the  moraine  in  Dekalb  County  (South  Kishwaukee  River  and  Owen's 
Creek)  have  only  a  small  amount  of  gravel  and  sand  outside  the  moraine, 
and  appear  not  to  have  been  lines  of  vigorous  discharge.  Sandy  material 
borders  Owen's  Creek  for  about  a  mile  each  side  the  stream  from  the  vicinity 
of  South  Grrove  northward  to  the  mouth.  The  material  is  full)^  as  fine  as 
that  on  Killbuck  Creek.  On  the  Kishwaukee  the  belt  of  sand  and  gravel 
is  less  definitely  outlined,  there  being  places  where  no  sand  or  gravel  is 
found  on  either  side  of  the  valley,  while  at  other  places  it  extends  back 
southward  from  the  valley  to  the  moraine,  a  distance  of  a  mile  or  more.  It 
is  probable  that  a  portion  of  this  sand  and  gravel  is  an  outwash  connected 
with  the  formation  of  the  moraine,  though  it  connects  rather  vaguely  with 
the  moraine. 

In  northwestern  Kane  Coimty  a  plain  of  sandy  gravel  extends  from 
the  moraine  westward  to  the  valley  of  Coon  Creek  and  leads  thence  down 
the  valley  to  the  north  Kishwaukee.  It  there  connects  with  belts  of  gravel 
which  lead  in  from  the  east  and  north,  all  of  which  appear  to  be  an  out- 
wash  from  the  western  border  of  the  composite  belt  of  moraines  in 
McHenry  County.  A  broad  belt  of  gravel  leads  down  the  north  Kishwau- 
kee to  its  junction  with  the  south  branch  near  Cherry  Valley.  Below  this 
point  the  valley  is  so  narrow  that  gravel  terraces  are  inconspicuous,  though 
they  continue  to  the  Rock  River  Valley. 

The  conditions  of  drainage  attending  the  formations  of  the  minor 
moraines  is  next  considered.  The  character  of  the  outwash  frc^m  tlie  weak 
moraine   in   northern   McLean  Count v  has   received    but    little   attention. 


THE  BLOOMINGTON  MORAmiC  SYSTEM.  279 

Gravel  deposits  of  medium  coai-seness  have  been  observed  at  and  above 
Lexington  on  the  headwater  portion  of  Mackinaw  River  near  the  outer 
border  of  the  moraine  They  underHe  the  plain  for  only  a  short  distance 
back  from  the  river  valley  at  these  points.  The  extent  of  these  deposits 
and  their  relation  to  the  moraine  have  not  been  ascertained.  It  seems 
probable,  however,  that  they  are  a  g-lacial  outwash. 

The  latest  of  the  moraines  in  the  Bloomington  system  follows  the  east 
border  of  the  Illinois- Vermilion  River  throughont  much  of  its  course,  a 
position  that  under  present  conditions  would  afford  fair  escape  for  the 
glacial  waters.  But  at  the  time  the  moraine  was  forming,  the  channel  now 
occupied  by  Vermilion  River  had  not  been  excavated.  The  broad  basin 
which  it  traverses  has  scarcely  20  feet  descent  in  the  40  miles  from  Pontiac 
to  the  borders  of  the  Illinois  River.  The  conditions  were  favorable  for  the 
ponding  or  accumulation  of  water  issuing'  from  the  ice  sheet,  as  well  as  for 
water  di'aining'  into  it  from  the  land  areas  on  the  southern  and  western 
borders.  A  belt  several  miles  in  width  might  have  thus  become  submerged 
and  a  lake-like  river  formed.  Even  though  the  volume  of  water  were  great, 
the  force  of  the  current  would  be  weak  until  the  channel  had  been  cut 
back  several  miles  into  the  basin.  The  opening  of  this  channel  has  been 
very  slow,  for  it  is  now  but  partly  accomplished,  the  main  part  of  the  chan- 
neling being  in  the  portion  below  Streator.  Evidence  of  a  ponding  of 
waters  in  this  basin  is  found  in  deposits  of  sand  and  silt  which  cover  it. 
The  sand  deposits  are  most  conspicuous  in  the  sotithern  portion  of  the 
basin,  and  are  there  drifted  in  places  into  low  dunes  and  ridges.  From 
Pontiac  southward  the  deposits  consist  of  silt  or  fine  sand.  The  ponding 
of  waters  and  deposition  of  sand  and  silt  probably  began  with  the  with- 
di'awal  of  the  ice  sheet  from  the  divide  on  the  west  border  of  the  basin, 
and  continued  until  the  ice  sheet  no  longer  contributed  its  waters  to  the 
basin.  This  would  involve  not  only  the  time  when  the  moraine  under  dis- 
cussion was  forming,  but  also  that  embraced  in  the  production  of  the  Mar- 
seilles moraine.  Possibly  the  ponding  continued  to  much  later  date,  though 
in  less  volume  than  at  the  morainic  substages  As  shown  below  (p.  290), 
there  was  a  discharge  into  this  basin  from  a  small  glacial  lake  held  in  the 
basin  of  the  Iroquois  River.  This  line  of  discharge  followed  the  east  fork 
of  Vermilion  River,  which  passes  through  the  moraine  under  discussion,  8 
to  10  miles  southwest  of  Pontiac.     The  character  of  the  outwash  appears 


280  THE  ILLII^OIS  GLACIAL  LOBE. 

to  have  varied  little  during  the  long  period  in  which  the  ice  sheet  dis- 
charged waters  into  this  basin.  For  a  few  miles  along  the  immediate  bor- 
ders of  the  river  below  the  point  where  the  East  Fork  enters  this  basin  a 
fine  gravel  occiirs,  which  was  probably  contributed  by  the  outlet.  There 
may  have  been  less  ponding  of  water  at  this  time  than  when  water  was 
contributed  by  the  ice  sheet  more  directly  to  the  basin.  This  subject  is 
discussed  more  fully  in  connection  with  the  glacial  lake  (pp.  290,  314,  336). 

No  doubt  the  Illinois  Valley  received  considerable  material  as  an  out- 
wash  from  this  minor  moraine,  but  as  yet  the  deposits  have  not  been  sepa- 
rated from  those  made  later,  and  nothing  is  known  concerning  the  degree  of 
coarseness  of  the  material. 

The  portion  of  the  moraine  north  from  the  Illinois  in  central  and 
northern  Lasalle  County  seems  to  have  been  no  better  favored  for  escape 
of  water  than  that  along  the  border  of  the  Illinois- Vermilion.  The  plain 
west  of  it  carries  thiu  deposits  of  silt,  but  whether  their  deposition  is 
largely  referable  to  water  issuing  from  this  moraine  is  not  known.  Pos- 
sibly wind  transportation  was  an  important  factor  in  the  deposition. 

INTERMORAINIC   TRACTS. 
EXTENT   OR   DISTRIBUTION. 

Under  this  topic  are  discussed  the  plains  and  gently  undulating  tracts 
among  the  ridges  of  the  Bloomington  system  and  a  plain  between  the  inner 
ridge  of  the  Bloomington  system  and  the  Marseilles  moraine.  The  inter- 
morainic  tracts  are  of  much  greater  extent  than  the  morainic,  for  the  latter 
are  restricted  to  narrow  belts.  About  90  per  cent  of  the  area  embraced 
between  the  inner  border  of  the  main  ridges  of  the  Bloomington  system 
and  the  outer  border  of  the  Marseilles  system  is  here  classed  as  nonmorainic. 
This  area  of  about  6,000  square  miles  ranges  in  width  from  25  to  about  50 
miles,  being  widest  in  central  Illinois.  It  has  a  length  of  about  175  miles 
between  northern  Kane  County,  Illinois,  where  it  connects  with  the  com- 
posite belt  of  moraines,  and  western  Benton  County,  Indiana,  where  it  is 
shut  off  by  moraines  of  late  Wisconsin  age. 

GENERAL   FEATURES. 

The  portion  north  of  the  Illinois  River,  embracing  southwestern  Kane, 
southeastern    Dekalb,    northwestern   Kendall,   northwestern   Lasalle,    and 


THE  BLOOMINGTON  MOEAINIC  SYSTEM.  281 

eastern  Bureau  counties,  shows  a  marked  descent  from  northwest  to  south- 
east and  a  less  marked  descent  from  northeast  to  southwest.  Its  altitiide 
along"  the  border  of  the  moraine  declines  from  about  800  feet  at  the  north- 
east  to  700  feet  at  the  southwest,  or  100  feet  in  a  distance  of  50  miles.  It 
declines  an  equal  amount  in  scarcely  26  miles  in  passing  from  the  border 
of  the  moraine  southeastward  to  the  bluff  of  Fox  River.  The  altitude 
along  the  bluff  of  this  river  ranges  from  about  700  feet  at  the  north  to  620 
feet  at  the  south.  Aside  from  the  narrow  morainic  belt  already  discussed, 
which  traverses  this  plain  from  Utica  northward  to  Earlville,  the  surface  is 
as  a  rule  only  slightly  undulatory.  There  are,  however,  a  few  short  eskers 
with  associated  chains  of  gravelly  knolls — discussed  below — and  also  scat- 
tering knolls  10  or  20  feet  in  height,  all  of  which  rise  somewhat  abruptly 
above  bordering  plains. 

South  from  the  great  bend  of  the  Illinois  River  the  features  are  more 
varied  than  in  the  district  just  touched  upon.  The  narrow  strip  on  the 
west  of  the  Illinois  Valley  descends  rapidly  from  the  moraine  to  the  river 
bluff.  It  has  a  gently  undulating-  surface,  with  a  tendency  to  north-south 
ridging.  East  from  the  Illinois  Valley  there  are  nearly  plane  tracts  inter- 
rupted by  sm'all  areas  with  undulatory  surface,  which  in  places  bear  strong 
resemblance  to  the  morainic  belts.  These  undulatory  tracts  are  most  abun- 
dant in  a  belt  a  few  miles  in  width  that  leads  southward  from  the  bend  of  the 
Illinois  through  eastern  Putnam,  eastern  Marshall,  and  east-central  Wood- 
ford counties,  its  eastern  edge  being  near  the  divide  between  tributaries  of 
the  Vermilion  and  streams  that  flow  westward  to  the  Illinois.  From  this 
divide  eastward  to  the  Vermilion  River  the  surface  shows  very  little  undu- 
lation. There  is,  however,  a  marked  descent,  the  altitude  of  the  divide 
being  700  to  750  feet,  while  the  immediate  borders  of  the  Vermilion  north 
from  Pontiac  stand  but  620  to  640  feet  above  tide.  The  descent  from  this 
divide  westward  to  the  Illinois  is  very  slight;  indeed,  in  places  east-west 
lines  are  nearly  level  from  this  divide  to  the  border  of  the  river  valley. 

There  is  a  small  tract  south  of  Ottawa,  occupying  the  interval  between 
the  inner  ridge  of  the  Bloomington  system  (Farm  Ridg-e)  and  the  Mar- 
seilles moraine,  which  has  a  nearly  plane  surface.  It  is  crossed  in  an  east- 
west  direction  by  a  sand  ridge,  discussed  below.  Another  sand  ridge 
follows  the  south  bluff  of  the  Illinois  part  way  across  this  plain.     Both 


282  THE  ILLINOIS  GLACIAL  LOBE. 

ridges  appear  to  mark  the  shores  of  a  lake-like  expansion  of  the  Illinois 
River,  and  represents  two  stages  differing  about  30  feet  in  level. 

In  northern  McLean  County  a  tract  embraced  between  the  inner  border 
of  the  main  ridges  of  the  Bloomington  system  and  the  Mackinaw  River 
Valley  is  gentlv  undulating  and  is  also  dotted  by  occasional  well-defined 
knolls  20  or  30  feet  in  heig'lit.  It  has  a  marked  northward  descent,  the 
elevation  along  the  Mackinaw  River  being  50  to  100  feet  below  the  inner 
border  of  the  moraine.  North  from  the  Mackinaw  River,  as  alreadv  noted, 
there  is  a  well-defined  ridge  (Cropsey  Ridge)  crossing  the  country  in  a 
WNW.-ESE.  direction.  From  this  ridge  there  is  a  gradual  northeastward 
descent  toward  the  Vermilion  River.  The  greater  part  of  the  surface  is 
plane  or  but  gently  undulating.  There  are,  however,  in  southern  Living- 
ston County  a  few  knolls  and  ridges  of  sand  10  or  20  feet  in  height. 
These  knolls  and  ridges  are  probably  the  result  of  wind  action  rather  than 
glacial  features. 

East  from  the  reentrant  angle  of  the  Bloomington  morainic  system  in 
Ford  and  southeastern  Li^■ingston  counties  there  is  a  plain  which  covers  the 
greater  part  of  Iroquois  County  and  extends  slightly  into  bordering-  counties. 
The  plain  is  bordered  at  the  north  by  the  ^Marseilles  morainic  svstem  and  at 
the  east  by  the  Iroquois  moraine,  a  moraine  of  late  ^Visconsin  age.  It 
extends  into  the  State  of  Indiana  only  a  few  miles,  in  northwestern  Benton 
County.  This  plain  descends  toward  the  north,  its  altitude  at  the  inner 
border  of  the  Bloomington  morainic  system  being  about  700  feet  and  in 
northern  Iroquois  County  only  about  625  to  650  feet.  It  is  crossed  nearly 
centrally  from  east  to  west  by  a  gently  undulatory  belt,  discussed  above  as 
a  possible  continuation  of  the  inner  member  of  the  Bloomington  system. 
Aside  from  this  belt  the  drift  surface  is  nearly  plane.  There  ai'e,  however, 
a  few  low  sandy  ridges  in  the  western  part  of  Iroquois  County  and  numer- 
ous dunes  in  the  eastern  part.  Some  of  these  ridges  appear  to  be  beaches 
of  a  temporary  lake,  as  indicated  below.  The  dunes  ai-e,  in  all  probability, 
a  result  of  wind  action  upon  the  sand  deposits  of  the  lake  bottom. 

THICKNESS   OF    DRIFT. 

There  are  present  beneath  these  intermorainic  tracts  a  sheet  of  fresh 
drift  of  Wisconsin  age  and  older  deposits  of  lowan  and  Illinoiau  age.  The 
thickness  of  the  Wisconsin  ilrift  may  be  ascertained  at  manv  places  by  the 


THE  BLOOMINGTON  MOEAINIC  SYSTEM.  283 

well  records,  which  show  a  change  from  soft  till  to  hard  at  the  base  of  this 
deposit.  It  is  much  less  than  on  the  morainic  ridges  of  the  Bloomington 
system,  and  probably  does  not  average  more  than  50  feet.  In  southern 
Kane  County  and  thence  southwest  along  the  border  of  Fox  River  it 
appears  to  be  but  20  to  40  feet,  but  at  the  inner  border  of  the  main  moraine 
in  Dekalb,  Lasalle,  and  Bureau  counties  it  is  in  places  100  feet  or  more. 
In  the  counties  bordering  the  Illinois  River  it  is  50  to  100  feet  or  more,  but 
in  the  Vermilion  Basin  it  scarcely  reaches  50  feet.  In  Iroquois  County  it 
is  50  to  100  feet. 

The  older  drift  deposits  are  thin  in  the  vicinity  of  Fox  River  and 
Vermilion  River  and  the  west-flowing  portion  of  the  Illinois  River,  but 
elsewhere  within  the  tracts  under  discussion  they  are  generall)^  present  in 
large  amount,  and  there  is  probably  an  average  thickness  as  great  as  that 
of  the  Wisconsin  drift  sheet.  In  portions  of  the  Iroquois  River  basin  200 
feet  or  more  of  the  older  drift  is  present,  but  in  the  remainder  of  the  tract 
a  thickness  exceeding  100  feet  is  i-are.  By  reference  to  the  detailed  dis- 
cussion of  the  wells  in  the  several  counties  embraced  within  these  inter- 
morainic  tracts  the  variations  in  thickness  may  be  seen. 

STRtlCTtIRE   OF   THE   DRIFT. 

Throughout  the  greater  part  of  the  area  embraced  in  these  inter- 
morainic  tracts  the  Wisconsin  di'ift  consists  mainly  of  a  moderately  stony, 
soft,  blue  till,  very  similar  to  that  found  in  the  moraines.  This  till  is 
replaced  by  sand  or  gravel  deposits  along  the  line  of  the  eskers  which  occur 
in  Kane  and  Dekalb  counties,  and  also  along  many  of  the  tributaries  of 
Fox  River.  There  is  also  considerable  sand  associated  with  the  till  in  a 
belt  several  miles  in  width  along  the  west  side  of  Fox  River  in  Kane,  Ken- 
dall, Dekalb,  and  Lasalle  counties.  On  the  borders  of  the  Vermilion  River 
in  Livingston  County  and  southern  Lasalle  County  sand  and  gravel  deposits 
predominate  over  the  till.  With  these  exceptions  the  till  greatly  predomi- 
nates over  the  sand  and  gravel.  In  many  localities  it  forms  so  solid  a  sheet 
that  strong  wells  are  not  obtained  in  it,  whereas  in  the  districts  in  which 
sand  and  gravel  predominate  over  the  till  abundance  of  water  is  obtained 
at  moderate  depths. 

The  drift  of  these  intermorainic  tracts  is  capped  only  by  thin  deposits 
of  silt,  seldom  exceeding  3  feet  in  depth,  and  in  places  too  thin  to  conceal 
the  surface  bowlders. 


284  THE  ILLINOIS  GLACIAL  LOBE. 

The  older  deposits  of  di-ift  appear  to  be  more  variable  tlian  the  Wis- 
consin sheet  within  the  area  under  discussion.  The  till  differs  from  that  of 
the  Wisconsin  sheet  in  being'  much  harder  to  penetrate  and  in  being  of  a 
gray  or  brown  color  rather  than  blue.  It  appears  to  contain  numerous 
pockets  or  intercalated  beds  of  gravel  or  sand,  for  strong  wells  may  usually 
be  obtained  in  it  in  localities  where  the  Wisconsin  drift  does  not  supply  a 
sufficient  amount  of  water.  The  outcrops  of  these  older  deposits  along  the 
ravines  or  A-alleys  tributary  to  the  Illinois  often  expose  a  cemented  gravel, 
in  beds  a  few  feet  in  thickness  and  a  few  rods  in  extent.  These  beds 
appear  to  lead  through  the  till  in  horizontal  bands  of  limited  width ;  pos- 
sibly they  are  buried  stream  beds  or  valley  gravels  formed  between  the 
reti-eats  and  advances  of  an  oscillating  ice  margin.  The  exposures  are 
insuflicieut  to  aff'ord  a  clear  idea  of  their  extent  and  connection.  It  seems 
not  improbable  that  these  beds  which  are  cemented  at  outcrops  along-  the 
valleys  become  open  textured  and  water  bearing-  where  unexposed.  There 
are  places  along  the  Illinois  Valley  and  its  tributaries  where  the  older  drift 
appears  to  be  composed  very  largely  of  sand  and  gravel,  but  as  a  rule  the 
till  predominates.  The  structm-e  of  the  drift  in  each  of  the  counties  com- 
prised in  this  intermorainic  area  is  shown  in  some  detail  in  the  discussion  of 
wells  which  accompanies  this  report. 

KANEVILLE  ESKER  AND  DELTA. 

0 

One  of  the  most  interesting  eskers  noted  in  Illinois  is  found  in  the 
southern  part  of  Kane  County.  Its  eastern  terminus  is  about  3  miles  west 
of  the  city  of  Aurora,  and  its  western  terminus  is  near  the  \'illage  of  Kane- 
viUe,  from  which  the  esker  has  received  its  name.  The  esker  occupies  a 
trough-like  valley  cut  in  glacial  deposits.  It  is  probable  that  the  valley 
was  formed  by  the  same  stream  which  deposited  the  esker,  since  they  coin- 
cide so  nearly  in  trend  and  position.  At  the  western  end  of  this  valley  there 
is  an  extensive  delta,  apparently  built  up  by  the  same  stream.  The  troi;gh- 
like  valley  is  now  travei'sed  by  Blackberry  Creek  in  the  reverse  direction 
from  the  supposed  flow  of  the  glacial  stream  which  produced  the  excava- 
tion and  formed  the  esker  and  delta.  The  valley  occupied  by  the  esker  is 
much  larger  than  that  of  the  lower  course  of  Blackberry  Ci'eek,  its  dimen- 
sions being  about  1  mile  in  width  and  30  feet  in  depth,  while  the  valley  of 
the  creek  below  the  point  where  it  leaves  this  trough  is  scarcely  20  I'ods  in 


U.S.GEOLOGIGAL   SURVEY. 


MONOGRAPH  XXXVIII  PL.  XIV. 


R   6  E 


R    7    E 


R   8  E 


R.6  E. 


R.7  E. 


R.8  E. 


JULIUS  aiEN  a  CO.  ".f 


■i  iiii  ill 


■  [^  ^ 


Morainic      Undulating  til!        Till  plain       Sandand  gravel    Bowlderhelts       Kiollsina     Ixanevilleesker        Slxice 

plainsaiidterraces  S'ravelplain 

GLACIAL  MAP  OF  PARTS  OF  I\ANE  AND  liENDALL  COUNTIES 

BY  FRANKLEVERETT 
Scale 


1898. 


THE  BLOOMINGTOK  MOEAINIG  SYSTEM.  285 

average  width  and  but  16  or  20.  feet  in  depth.  The  trough-like  valley  is 
therefore  about  30  times  as  large  as  the  portion  of  Blackberry  Creek  Val- 
ley below  its  eastern  end.  This  broad  valley  was  apparently  cut  to  such 
depth  before  the  creek  entered  it  that  the  latter  has  tended  to  fill  it  by  over- 
flows in  time  of  freshet,  and  has  deepened  it  only  in  the  immediate  bed  of 
the  stream. 

The  eastern  end  of  the  esker  is  found  in  sec.  18,  Aurora  Township,  on 
a  till  plain  which  borders  Fox  River.  There  is  here  a  ridge  of  gravel  some 
60  rods  in  length  and  10  or  20  rods  in  width,  which  rises  but  12  to  15  feet 
above  the  bordering  plain.  For  a  mile  or  more  west  from  this  ridge  there 
ai'e  only  occasional  small  gravel  deposits  in  the  form  of  knolls  and  short 
ridges,  but  as  soon  as  the  trough-like  valley  is  fairly  entered  the  gravel 
becomes  more  abundant.  (See  PI.  XIV.)  It  forms  a  winding-  ridge  20  to  60 
feet  in  height,  and  inteiTupted  only  by  occasional  narrow  gaps.  Its  slopes 
are  very  abnipt,  rising  frequently  with  an  angle  of  30°.  In  the  northwest 
part  of  sec.  31,  Blackben-y  Township,  about  7  miles  from  the  eastern  end, 
the  esker  rises  from  the  deeper  portion  of  the  valley  and  lies  along  its  south 
slope.  Here  also  it  changes  from  a  single  sharp  ridge  to  a  tumultuous  series 
of  knolls  and  winding  ridges,  inclosing  basins  30  to  40  feet  or  more  in  depth 
and  having  a  diameter  of  but  10  or  20  rods.  This  belt  has  a  width  of  about 
^one-third  of  a  mile,  and  extends  westward  nearly  a  mile.  Just  north  of 
this  main  belt  there  are,  in  the  deeper  part  of  the  valley,  occasional  gravel 
knolls  and  low  winding-  ridges.  These  low  ridges  rise  from  the  trough  at 
its  western  end,  and  together  with  the  main  belt  lose  themselves  in  the 
gravel  delta  near  Kane-\dlle,  the  delta  being  built  up  nearly  as  high  as  the 
crests  of  the  ridges. 

The  delta  occupies  an  area  of  about  8  square  miles.  It  stands  a  few 
feet  higher  than  the  till  plain  which  borders  it  on  the  north,  west,  and  south. 
The  gravel  apparently  extends  in  places  below  the  level  of  this  till  plain,  for 
in  two  cases  wells  have  penetrated  to  a  depth  of  60  feet  without  reaching  its 
bottom.  In  the  village  of  Kaneville,  which  is  situated  in  the  midst  of  the 
delta,  the  wells  are  usually  in  gravel  to  a  depth  of  30  or  40  feet.  In  a  few 
instances,  however,  clay  beds  were  passed  through  in  the  lower  portion  of 
the  wells. 

There  are  numerous  small  excavations  in  the  esker  which  show  it  to  be 
formed  of  sand  and  gravel  in  neai'l}-  horizontal  beds.     In  places  the  beds 


286  THE  ILLINOIS  GLACIAL  LOBE. 

have  a  sharp  dip  toward  the  sides  of  the  esker,  but  this  does  not  appear  to 
be  a  general  attitude.  The  upper  part  and  frequently  the  slopes  consist  of 
coarser  gravel  and  contain  less  fine  material  than  the  deeper  portions.  The 
absence  of  fine  pai'ticles  is  perhaps  attiibutable  in  part  to  the  action  of  per- 
colating waters,  which  probably  have  sufficient  force  to  carry  down  the 
finer  particles  a  few  feet  from  the  surface,  but  it  is  probable  that  the  sm-face 
portion  was  originally  coarser  than  the  deeper  beds.  The  pebbles  are  mainly 
limestone  and  are  appai-ently,  in  large  part,  from  the  Lockport  (Niagara) 
limestone,  which  outcrops  in  the  neighboiiug  district  on  the  east.  The  sand 
is  calcareous,  but  not  to  such  a  degree  as  in  many  hillocks  containing  sand 
and  gTavel  which  occur  in  the  neighboring  moraines.  It  seems  probable  that 
the  material  of  which  the  esker  is  composed  is  a  residue  left  upon  the  exca- 
vation of  the  till  which  was  removed  along  the  course  of  the  valley  or  of 
material  embedded  in  the  basal  portion  of  the  ice  sheet.  Examinations  of  a 
sample  of  the  till  from  a  neighboring  till  plain  showed  that  93  per  cent  of 
the  pebbles  are  limestone,  which  is  about  the  percentage  of  limestone  in  the 
esker. 

Bowlders  were  observed  on  the  esker  in  but  one  place,  and  this  was  at 
a  slight  depression  on  its  crest.  There  were  about  30  of  them,  and  all  were 
of  Archean  rocks.  The  greater  percentage  of  Ai-chean  rocks  on  the  sui-face 
than  in  the  deeper  portions,  both  of  eskers  and  till  sheets,  appai-ently  indi- 
cates a  different  source  for  the  bowlders  than  that  of  the  main  body  of  the 
drift.     Presumably  they  were  carried  at  a  higher  elevation  in  the  ice. 

•     LITTLE   ROCK  ESKER   OR   "DEVIL'S   BACKBONE." 

In  the  northwest  part  of  Squaw  Grrove  Township  (T.  38,  R  5  E.), 
Dekalb  County,  there  is  an  esker  about  1  ^  miles  in  length,  known  by  the 
residents  as  the  "  Devil's  Backbone."  It  is  situated  a  short  distance  south 
of  Little  Rock  Creek  in  sees.  5  and  6,  and  trends  ESE.-WNW.  At  the 
eastern  end  its  height  is  but  4  to  6  feet,  but  in  sec.  6  it  is  10  or  15  feet  in 
height.  It  is  onl)^  8  or  10  rods  in  width,  including  slopes,  and  consequently 
presents  very  abrupt  slopes.  It  winds  considerably,  but  has  a  somewhat 
even  crest  line.  At  the  western  end  there  is  a  sandy  tract  covering  about  80 
acres,  which  is  thought  to  be  a  delta  formed  in  connection  with  the  esker. 
There  is  no  valley  or  trougli  excavated  in  the  di'ift,  as  in  the  case  of  the  Kane- 
ville  esker,  for  tlie  esker  stands  at  aljout  tlie  level  of  the  bordering  till  plain. 


THE  BLOOMINGTOK  MORAINIO  SYSTEM.  287 

Wells  in  the  delta  penetrate  10  to  15  feet  of  sand  before  entering  till.  The 
esker  is  opened  at  numerous  points,  and  there  is  usually  3  or  four  feet  of 
coarse  gravel  at  the  surface,  beneath  which  is  a  finer  gravel.  In  jjlaces  the 
bedding  is  found  to  have  a  dip  toward  the  northwest,  nearly  in  line  with 
the  general  trend  of  the  ridge.  The  coarse  gravel  curves  over  the  ridge, 
covering  slopes  as  well  as  crest.  The  pebbles  are  principally  limestone 
and  are  usually  well  rounded. 

There  are  a  few  short  gravel  ridges  and  knolls  east  from  the  end  of 
this  esker  in  sees.  4,  11,  and  12,  but  they  do  not  seem  to  be  definitely 
connected  with  one  another  or  with  the  esker.  Their  trend,  like  that  of  the 
esker,  is  ESE.-WNW.  The  same  system  of  glacial  drainage  which  formed 
the  esker  may  have  been  influential  in  forming  these  knolls  and  ridges. 

Mention  should  also  be  made  of  a  chain  of  gravelly  knolls  which 
follows  a  tributary  of  Somonauk  Creek  in  southeastern  Clinton  Township 
(T.  38,  R.  4  E.),  Dekalb  County.  Though  following  the  creek  border 
closely,  they  are  evidently  not  the  result  of  erosion  by  the  creek,  for  they 
stand  above  the  general  level  of  the  bordering  plain.  They  range  in  height 
from  10  to  25  feet.  Their  width  is  iisually  15  to  30  rods  and  the  length 
varies  from  one-fourth  mile  or  less  to  fully  one-half  mile.  They  are  chiefly 
on  the  south  border  of  the  stream,  but  two  were  obsei-ved  on  its  north 
border.  They  are  not  strictly  in  line  with  each  other,  though  a  belt  a  half 
mile  wide  would  include  the  entire  system.  The  length  of  the  system  is 
about  4  miles,  the  western  end  being  2^  miles  south  of  Waterman  and  the 
eastern  end  at  Somonauk  Creek  Valley  in  the  southwest  part  of  Squaw 
Grrove  Township.  One  of  these  knolls  has  an  extensive  gravel  pit  in  which 
the  following  beds  are  exposed: 

Section  in  gravel  pit  on  hnoll  in  Clinton  Toivnship,  Dekalb  County,  Illinois, 

Feet 

Brown  clay  -with  a  few  clierty  pebbles 4 

Coarse  gravel,  maiuly  limestone  pebbles 6 

Fine  gravel  and  sand  in  alternate  layers,  each  6  inches  or  more  in  thickness 4 

Several  other  small  excavations  have  been  made  in  these  gravel  knolls 
which  show  a  section  similar  to  the  above.  The  stratification  in  every  case 
is  nearly  horizontal. 

There  are  also  knolls  of  a  different  tyjoe  found  on  this  plain  which 
include  much  till  as  well  as  assorted  material.  One  of  these  knolls,  situated 
about  2  miles  northwest  of  Leland,  contains  an  extensive  gravel  pit  which 


288  THE  ILLINOIS  GLACIAL  LOBE. 

displays  its  stracture  from  top  to  bottom.  The  knoll  is  capped  by  a  browu 
clay,  containing  few  pebbles.  Beneath  this  there  is  at  the  east  side  of  the 
knoll  considei'able  sand,  but  toward  the  center  there  is  a  series  of  till  or  clay 
beds  12  to  20  inches  iu  thickness,  interstratified  with  gravel  and  sand  beds 
each  2  or  3  feet  in  thickness.  All  the  beds  dip  toward  the  center  of  the  hill 
at  an  angle  of  15  degrees  or  more.  The  till  is  very  hard  and  pebbly.  The 
gravel  contains  a  much  larger  percentage  of  crystalline  rocks  of  Canadian 
derivation  than  is  common  in  knolls  and  eskers  made  up  eutu'ely  of  assorted 
material,  though  there  are  many  limestone  pebbles  such  as  may  have  been 
derived  from  ledges  in  the  neighboring  districts  on  the  east.  This  knoll 
stands  15  to  20  feet  above  the  bordering  plain  and  about  30  feet  above  the 
flood  plain  of  Little  Indian  Creek,  which  touches  it  on  the  east. 

COVEL    RIDGE. 

In  the  plain  di-aiued  by  Covel  Creek,  a  southern  tributary  of  the  Illinois, 
entering  just  below  Ottawa,  there  is  a  low  ridge  about  7  miles  in  length 
extending  in  a  nearly  due  east-west  direction  from  near  the  outer  border  of 
the  Marseilles  moraine  in  sec.  4,  Grand  Rapids  Township  (T.  32,  R.  4  E.), 
to  the  inner  slope  of  Farm  Ridge  the  inner  ridge  of  the  Bloomington 
system  in  sec.  5,  Farmridge  Township  (T.  32,  R.  3  E.).  It  has  a  height  of 
15  or  20  feet  and  a  width  of  40  to  60  rods,  and  is  interrupted  by  no  gaps 
of  consequence  except  the  one  through  which  Covel  Creek  passes  in  sec.  6, 
Grand  Rapids  Township,  and  this  gap  is  only  30  or  40  rods  in  width.  The 
altitude  of  the  crest  of  this  ridge,  as  shown  by  the  Ottawa  topographic 
sheet,  a  portion  of  which  is  reproduced  in  PI.  XIX,  is  mainly  between  640 
and  650  feet  above  tide.  The  portion  east  of  Covel  Creek  is  represented 
to  be  slightly  lower  than  640  feet. 

The  ridge  is  capped  b}"  a  brown  silt  several  feet  in  thickness  which  is 
readily  peiwious  to  water.  This  is  underlain  by  sand  which  extends  to  a 
depth  of  15  or  20  feet  or  more.  The  few  wells  which  have  been  made  on 
the  ridge  are  sunk  no  deeper  than  20  feet.  The  sand  also  extends  oiit 
beneath  the  bordering  plain  a  short  distance  both  north  and  south  of  the 
ridge  and  affords  water  for  wells  at  slight  depth.  The  extension  beneath 
tlie  plain,  however,  seldom  exceeds  a  mile  in  width  or  half  a  mile  from  the 
crest  of  the  ridge.     Border  districts  are  underlain  at  slight  depth  by  till. 

The  internal  structure,  the  form,  and  the  uniform  elevation  of  tlie  ridge 


THE  BLOOMIjSTGTON  MORAINIC  SYSTEM.  289 

suo-o-est  the  interpretation  that  it  is  a  beach  Hne.  However,  this  interpreta- 
tion scarcelv  affords  a  satisfactory  explanation  of  the  mode  of  deposition  of 
the  silty  mantle;  hence  the  question  of  its  mode  of  formation  is  left  open. 
There  is  a  lower  ridge  following-  the  brow  of  the  Illinois  bluff,  which 
is  well  displaj^ed  in  South  Ottawa,  and  eastward  from  there  to  the  border 
of  the  Marseilles  moraine.  Its  altitude,  as  shown  by  the  Ottawa  topo- 
graphic sheet,  is  very  nearly  610  feet  above  tide.  Along-  the  north  bluff 
of  the  Illinois,  about  midway  between  Ottawa  and  Marseilles,  there  is 
another  beach-like  ridge  leading  from  the  outer  border  of  the  Marseilles 
moraine  westward  to  the  border  of  Fox  River  Valley,  which  is  represented 
to  stand  a  few  feet  lower  than  the  ridge  just  noted,  its  altitude  being  600 
feet  or  less. 


ONARGA    RIDGE. 


In  the  Iroquois  Basin  there  are  several  small  ridges  of  sand  presenting 
the  appearance  of  beach  lines,  some  being  found  in  the  northwest  part  of 
Iroquois  County,  a  short  distance  south  of  the  Marseilles  moraine,  and 
others  on  portions  of  the  plain  farther  south.  The  best-defined  and  most 
elevated  ridge  noted  is  one  leading  from  Onarga  westward  through  Ridge- 
ville  to  one  of  the  headwater  forks  of  Vermilion  River,  the  west  end  being 
near  the  line  of  Iroquois  and  Ford  counties,  about  4  miles  southeast  of 
Piper.  Throughout  this  distance  of  about  8  miles  it  has  a  width  of  only 
40  to  80  rods  and  a  height  of  15  or  20  feet  or  less.  As  far  as  could  be 
ascertained  from  the  slight  exposures  and  records  of  occasional  wells  it  is 
composed  entirely  of  sand.  It  is  underlain  at  the  level  of  its  base  by  a 
bluish-yellow,  silty,  pebbly  clay,  which  grades  below  into  bliie  till.  In 
some  places  the  sand  is  immediately  underlain  by  blue  till.  As  a  rule  the 
ridge  has  a  smooth  surface  and  gentle  slopes,  but  in  places  the  sand  is 
drifted  into  low  dunes  6  or  10  feet  in  height.  The  sand  is  of  a  brown  color 
and  so  far  as  tested  shows  no  effervescence  with  acid.  A  short  distance  east 
from  the  eastern  edge  of  this  ridge  a  belt  of  low  sand  dunes  sets  in,  which 
has  a  width  of  1  to  2  miles.  This  belt  leads  eastwai'd  to  the  vicinity  of 
Watseka,  and  thence  northward  and  eastward  to  the  Kankakee  Basin, 
occupying  much  of  northeastern  Iroquois  County. 

The  elevation  of  the  Onarga  Ridge  is  about  675  feet  above  tide,  but  the 
duues  to  the  east  seldom  reach  this  elevation,  the  district  covered  by  them 
HON  xxxvm 19 


290  THE  ILLINOIS  GLACIAL  LOBE. 

having-  generally  an  elevation  of  640  to  650  feet.  Possibly  a  shore  line 
may  be  found  south  and  east  of  the  dunes  at  an  elevation  corresponding  to 
that  of  the  Onarga  Ridge,  but  as  yet  it  has  not  been  discovered.  It  seems 
probable  that  this  ridge  marks  the  south  shore  of  a  temporary  lake  which 
discharged  westward  through  the  east  fork  of  Vermilion  River.  If  there 
were  no  obstructions  at  the  north,  a  northward  discharge  from  the  Iroquois 
Basin  would  seem  to  be  more  natural,  for  the  country  descends  in  that  direc- 
tion. The  only  known  former  obstruction  is  that  caused  by  the  presence 
of  the  ice  sheet,  in  which  case  this  beach  may  be  interpreted  as  the  shore 
of  a  glacial  lake.  The  writer's  studies  have  not  been  sufficiently  detailed 
to  justify  a  full  interpretation  of  the  phenomena.  Other  features  of  similar 
character  are  discussed  below  (pp.  336-338). 

SECTION  IV.    THE  COMPOSITE  MORAINIC  BELT  OF  NORTHERN 

ILLINOIS. 

Numerous  references  have  been  made  in  previous  pages  to  a  composite 
belt  of  moraines  with  which  the  Bloomington  system  connects  in  northern 
Kane  County,  and  which  marks  the  continuation  of  the  Bloomington  system, 
together  with  that  of  later  morainic  systems  which  are  there  intimately 
associated  with  it.  This  composite  belt  admits  of  but  little  separation  into 
distinct  moraines.  It  seems  advisable,  therefore,  to  give  it  treatment  inde- 
pendent of  each  of  the  morainic  systems  which  lead  away  from  it,  leaving 
open  to  a  large  degree  the  question  of  precise  correlation.  This  belt  is 
made  to  include  a  somewhat  distinct  moraine,  called  the  Marengo  Ridge, 
which  lies  along  its  western  border.  The  discussion  of  this  ridge  is  first 
taken  up ;  the  remaining  portion  of  the  composite  belt  west  of  Fox  River  is 
next  considered,  and  this  is  followed  by  a  discussion  of  the  portion  east  of 
Fox  River. 

MARENGO  RIDGE. 
DISTRIBUTION. 

North  from  the  village  of  Hampshire  in  Kane  County,  as  far  at  least 
as  the  State  line,  the  Marengo  Ridge  constitutes  the  outer  moraine  of  the 
Wisconsin  series,  and  it  probably  continues  to  be  the  outer  moraine  to  its 
junction  with  the  Kettle  moraine  of  the  Green  Bay  lobe  in  western  Wal- 
worth County,  Wisconsin.'     Tlie  ridge  receives  its  name  from  the  village  of 


'SeeT.  C.  Chamborliu;  Third  Ann.  Rept.  U.  S.  Geol.  Survey,  p.  322;  also  PI.  XXXI. 


COMPOSITE  MOEAINIC  BELT  OF  NORTHBRX  ILLINTOIS.  291 

Marengo,  which  is  situated  in  the  line  of  the  ridge,  but  wliich  stands  in  the 
North  Kishwaukee  Valle  j.  It  is  the  only  town  in  Illinois  in  the  direct  line 
of  the  ridge,  though  Harvard  in  McHenr)?-  County  and  Hampshire  in  Kane 
County  are  situated  near  the  foot  of  the  outer  slope. 

From  the  State  line  the  course  of  the  ridge  is  nearly  due  south  to 
Marengo,  from  which  point  it  bears  southeast  to  the  south  line  of  McHenry 
County.  It  then  resumes  a  southward  course  and  continues  for  about  18 
miles  to  the  vicinity  of  Elburn,  in  Kane  County,  where  it  becomes  united 
with  the  portion  of  the  composite  belt  to  the  east.  It  will  be  observed  that 
it  passes  by  the  eastern  end  of  the  outer  Bloomington  ridge  near  Hamp- 
shu-e.  The  ridge  thi'oughout  the  greater  part  of  its  course  has  a  width, 
including  slopes,  of  3  or  4  miles. 

BELIEF. 

The  relief  of  the  outer  border  is  seldom  less  than  100  feet,  and  in  places 
it  reaches  150  feet  or  more.  The  inner  border  has  a  relief  of  75  to  120  feet, 
but  the  relief  appears  less  bold  than  on  the  outer  border,  because  the  ascent 
to  the  crest  is  more  gradual.  This  ridge  is  closely  associated  with  the 
remainder  of  the  belt  for  a  few  miles  south  from  the  State  line,  and  differs 
but  little  in  altitude  from  the  district  on  the  east.  Similarly  at  the  south, 
where  it  connects  with  the  remainder  of  the  belt,  it  has  about  as  great  an 
altitude. 

SURFACE   CONTOUES. 

From  the  State  line  southward  to  Hampshii-e  this  ridge  presents  a  char- 
acteristic knob-and-basin  topography,  so  well  develojied  in  the  Wisconsin 
Kettle  moraine  and  described  by  Chamberlin  as  being  "of  an  exceedingly 
irregular,  intricate  character,  formed  by  knobs,  peaks,  short  irregular  hills  and 
spurs  associated  in  complex  order,  interspersed  with  hollows  and  depressions 
of  like  irregular  character,  often  without  outlet."^  The  larger  knobs  rise 
scarcely  50  feet  above  the  neighboring  basins,  and  the  average  height  of 
the  knobs  is  probably  not  more  than  25  feet.  They  are  found  both  on  the 
crest  of  the  ridge  and  on  the  slopes.  Aside  from  the  well-defined  basins, 
there  are  shallow,  saucer-like  depressions  found  frequently  on  the  top  of  the 
knolls  and  the  slopes  of  knolls  and  ridges,  as  well  as  in  the  sags  between 
them.     There  is  a  marked  distinction  between  the  contours  of  the  prame 

'  Third  Ann.  Kept.  U.  S.  Geol.  Survey,  1883,  p.  307. 


292  THE  ILLmOIS  GLACIAL  LOBE. 

aud  of  the  wooded  portion  of  the  ridg-e,  the  contours  being  niucli  sharper  in 
the  forest  than  on  the  prairie.  The  ridge  is  mainly  forest-clad  from  the 
State  line  sonth  to  the  vicinity  of  Hampshire  and  mainly  praii-ie  from 
Hampshire  to  Elburn.  This  difference  in  the  sharpness  of  contour  may  be 
due  in  part  to  the  effect  of  the  agencies  of  degradation,  the  wooded  portion 
of  the  ridge  being  better  protected  from  these  agencies.  It  is  probable, 
however,  that  the  prairie  portion  was  originally  possessed  of  smoother  con- 
tour. It  presents  a  series  of  billows,  often  40.  or  50  feet  high  and  60  to  80 
rods  or  more  in  diameter,  whose  slopes  are  usually  smooth  and  regular.  As 
indicated  below,  the  relation  of  the  southern  portion  of  the  ridge  to  the  ice 
margin  may  be  somewhat  different  from  that  north  of  Hampshire. 

There  are  three  gaps  in  this  ridge  worthy  of  mention.  The  largest  is 
that  at  Marengo,  through  which  the  North  Kishwaukee  passes.  It  is  fully 
150  feet  in  depth  and  about  2  miles  in  width.  The  second  gap  occurs  about 
5  miles  southeast  of  Marengo.  This  is  nearly  a  mile  in  width,  but  only 
about  76  feet  lower  than  the  neighboring  portions  of  the  ridge.  It  has  a 
nearly  plane  surface,  and  has  apparently  been  utilized  as  a  line  of  discharge 
for  a  body  of  water  formerly  held  between  this  ridge  and  the  one  on  the 
east.  A  third  gap  occm-s  in  the  north  part  of  T.  40,  R  7  E.  It  is  60  or 
70  feet  in  depth  and  about  one-half  mile  in  width.  It  has  a  nearly  plane 
surface  and  was  probabl}?"  at  one  time  a  line  of  discharge  for  water  held 
between  this  ridge  and  a  moraine  on  the  east.  It  is  now  utilized  by  a  trib- 
utary of  the  South  Kishwaukee  River. 

THICKNESS    OF   DRIFT. 

The  thickness  of  drift  has  been  ascertained  at  only  three  points,  but 
records  of  several  deep  wells  were  obtained  which  show  that  there  is  a  heavy 
accumulation  along  the  entire  length  of  the  ridge.  Of  the  three  borings 
reaching  rock,  one  is  in  the  village  of  Harvard  and  the  other  two  are  in  the 
southern  part  of  the  ridge.  At  Harvard  the  thickness  is  102  feet.  In  the 
other  weJls  the  rock  was  struck  in  one  instance  at  230  feet  and  in  the  other 
at  about  250  feet.  It  is  probable  that  the  general  thickness  of  the  drift 
along  the  crest  of  the  ridge  south  from  Hampshire  is  not  far  trom  250  feet, 
for  wells  on  the  plain  west  of  the  ridge,  at  an  altitude  100  to  125  feet  below 
the  level  of  its  crest,  have  in  several  instances  struck  rock  at  about  150  feet. 
One  well  on  the  ridge,  near  Lily  Lake  reached  a  depth  of  336  feot  without 


COMPOSITE  MOEAraiO  BELT  OF  NORTHERN  ILLINOIS.  293 

entering  rock.  In  the  portion  north  from  Hampshire  the  thickness  is  prob- 
ably not  much  greater  than  the  rehef  of  the  ridge,  for  rock  is  enconntered 
at  a  depth  of  50  feet  or  less  in  much  of  the  border  district  on  the  west.  The 
drift  referable  to  the  invasion  which  formed  this  ridge  has  probably  a  thick- 
ness about  equal  to  the  relief  of  the  ridge,  which,  as  stated  above,  is  usually 
100  to  150  feet  or  more. 

STRUCTURE    OF    THE    DRIFT. 

The  ridge  is  composed  mainly  of  blue  till.  Sand  and  gravel  beds  are 
not  sufficiently  extensive  to  afford  a  general  water  supply.  Even  weak 
wells  are  difficult  to  obtain  in  some  parts  of  the  ridge.  Many  wells  must 
be  sunk  100,  125,  or  even  150  feet  to  obtain  an  adequate  water  supply.  In 
not  a  few  instances  the  water  supply  appears  to  be  obtained  at  about  the 
level  of  the  base  of  the  ridge  and  the  junction  between  the  Wisconsin  and 
older  drift  sheets. 

A  few  gravelly  knolls  were  noted  along-  the  outer  border  of  the  ridge 
west  of  Marengo,  and  at  occasional  points  between  there  and  Hampshire. 
None  of  these  rise  more  than  10  feet  above  the  general  level.  A  few  gravel 
knolls  were  noted  near  East  Bin-lington,  in  sees.  23,  24,  25,  and  26,  T.  41, 
R.  6  E.,  and  low  gravel  ridges  occur  along  the  ti'ibutaries  of  the  South 
Kishwaukee  in  Ts.  40  and  41,  R.  6  E.  Excavations  in  these  knolls  usually 
show  a  preponderance  of  sand  and  gravel  over  till,  though  the  latter  is  often 
present  in  considerable  amount.  The  beds  have  no  apparent  uniformity  in 
direction  or  degree  of  dip.  They  are  often  curved  and  disturbed  as  if 
affected  by  movements  of  the  ice  sheet  over  them. 

The  presence  of  a  buried  soil  was  noted  in  several  well  borings  of 
which  records  were  obtained.  In  the  city  of  Marengo,  on  the  borders 
of  Kishwaukee  Valley,  it  is  found  at  a  depth  of  30  to:  60  feet,  the  variation 
in  distance  being  due  to  difference  in  elevation  of  the  wells.  In  sec.  11, 
T.  43,  R.  5  E.,  a  well  on  the  outer  slope  of  the  moraine  struck  a  buried  soil 
at  70  feet.  The  soil  was  underlain  by  a  soft  whitish  clay  of  slight  depth, 
beneath  which  gravel,  5^ielding  water,  was  found.  In  the  cases  just  noted 
the  soil  seems  referable  to  the  Peorian  interglacial  stage.  A  buried  soil 
was  noted  in  one  of  the  deep  borings  in  T.  40,  R.  7  E.,  which  reached  the 
bottom  of  the  drift.  This  soil,  as  noted  on  a  preceding  page,  seems  to  be 
at  a  level  low  enough  to  be  referred  to  the  Sangamon.     The  boring  is  on 


294  THE  ILLINOIS  GLACIAL  LOBE. 

the  farm  of  James  Powell,  in  sec.  7,  near  the  crest  of  the  ridge,  and  the 
section  is- as  follows: 

Section  of  James  PoicelVs  boring  near  Lily  Lake,  Illinois. 

Feet. 

Pebbly  soil 1 

Brownish-yellow  pebbly  clay 15 

Graj'ish-blue  pebbly  day 180 

Black  mucky  soil 2 

Greenisli  clay 3 

Hard  pebbly  clay  of  brownish-blue  color 40 

Santl 2 

Hard  clay 8 

Limestone 200 

Total  depth 450 

The  thickness  of  the  yellow  till  in  the  above  well  section  is  greater  than 
the  average,  though  instances  were  found  in  which  the  till  presented  a  yel- 
lowish color  to  a  depth  of  35  feet  from  the  surface.  The  average  depth  of 
the  yellow  till  is  about  10  feet.  Several  sections  of  wells  along  this  ridge 
are  presented  below  in  the  discussion  of  the  wells  of  Illinois.  The  till  is 
thought  by  some  well  di-illers  to  be  slightly  more  stony  in  the  ridges  than 
on  plane  tracts  in  McHenry  and  Kane  counties,  but  the  difference  is  not 
very  marked.  Surface  bowlders  are  common  over  the  entire  length  of  the 
ridge,  and  in  a  few  places  are  very  numerous.  They  are  especially  abun- 
dant in  the  vicinity  of  the  McHenry-Kane  county  line  and  also  near  East 
Burlington.  Bowlders  are  composed  mainlj'  of  granitic  and  other  rocks  of 
Canadian  derivation,  limestones  and  local  rocks  being  rarely  found  at  the 
surface.  In  the  till,  however,  limestone  rocks  are  a  conspicuous  ingredient, 
and  also  in  the  kames  or  gravelly  knolls. 

CHARACTER   OF   OUTWASH. 

Along  the  outer  or  western  border  of  this  ridge  from  the  State  line 
southward  to  Hampshire  there  is  a  nearly  continuous  gravel  plain  formed 
apparently  as  an  outwash  from  the  ice  sheet.  It  extends  out  usually  a  mile 
or  more  from  the  foot  of  the  moraine,  and  leads  westward  down  the  Kish- 
waukee  Valley  to  Rock  River.  From  Hampshire  southward  the  plain  out- 
side ^Marengo  Ridge  is  nearly  free  from  coarse  outwash  and  carries  only 
slight  deposits  of  silt  and  sand. 

Tlie  gravel  plains  usually  have  a  capping  of  loamy  clay  2  to  6  feet  or 
more  in  depth,  which  gives  them  great  fertility.  Beneath  this  clay  ^re  beds 
of  sand  and  gravel  which  show  considcrahlc  variety  in  coarseness  in  vertical 


ti' 


COMPOSITE  MOEAINIC  BELT  OF  NORTHERN  ILLINOIS.  295 

section.  They  vary  also  iu  coarseness  from  place  to  place  at  the  same  hori- 
zon. On  the  border  of  the  gravel  plains  the  assorted  material  rests  upon 
beds  of  till  belonging-  to  the  older  drift,  and  the  depth  is  often  insufficient 
to  afford  water  for  wells.  In  the  middle  portions  of  the  gravel  plains  the 
wells  do  not  reach  the  bottom  of  the  sand  and  gravel.  Along  the  Kish- 
waiikee  near  Marengo,  Capt.  Fred  Smith,  a  well  driller,  has  in  some  cases 
Slink  wells  to  a  depth  of  100  feet  mainly  through  gravel,  but  it  is  not  cer- 
tain that  this  deposit  should  be  entirely  referred  to  the  outwash  from  the 
ice  at  the  time  the  Marengo  Ridge  was  forming. 

INNEK-BOEDER   PHENOMENA. 

On  the  inner  border  of  the  Marengo  Ridge  there  is,  in  Kane  County, 
a  narrow  plain  1  to  2  miles  in  width,  separating  it  from  the  remainder  of 
the  composite  belt.  This  plain  is  generally  very  level  and  in  places  is 
poorly  drained.  It  is  underlain  in  part  by  sand  and  in  part  by  till.  The 
greater  part  is  now  tributary  to  Fox  River,  but  the  southern  portion  finds  a 
discharge  westward  into  the  Kishwaukee  through  a  gap  in  the  Marengo 
Ridge,  as  noted  above.  In  McHenry  County  the  inner  border  of  the 
Marengo  Ridge  is  largely  occu^jied  by  gravel  plains  which  are  connected 
with  the  portion  of  the  composite  belt  on  the  east.  Along  the  borders  of 
these  gravel  plains  there  are  nearly  level  tracts  underlain  at  slight  depth 
by  till. 

At  present  the  gravel  plains  on  both  the  inner  and  the  outer  border  of 
the  Marengo  Ridge  are  occupied  b}^  insignificant  streams  which  seldom 
fill  the  small  ditches  leading  through  the  broad  plains.  They  are  certainly 
inadequate  to  have  deposited  tlie  vast  amount  of  assorted  material  here 
present,  and  the  fact  that  these  gravel  deposits  set  in  at  the  base  of  the 
moraines  in  just  such  positions  as  streams  of  water  escaping  from  the  border 
of  the  ice  sheet  would  occupy,  apparently  leaves  no  room  to  question  the 
interpretation  that  the  gravel  is  an  outwash  from  the  ice  margin.  These 
gravel  deposits,  it  is  thought,  testify  as  clearly,  though  perhaps  in  a  less 
impressive  manner,  to  the  influence  of  the  ice  sheet  as  does  the  great  ridge 
of  commingled  drift  formed  at  the  ice  border. 

CORRELATIONS. 

The  correlations  of  this  ridge  with  moraines  farther  south  can  scarcely 
be    said   to   be    settled.      Several    interpretations    are    suggested    by   the 


296  THE  ILLINOIS  GLACIAL  LOBE. 

phenomena.  By  one  interpretation  tlie  portion  of  tlie  ridge  from  Hampshire 
northwai-d  is  considered  a  continuation  of  the  Bloomiugton  system,  while 
the  portion  south  from  Hampshire  is  merely  a  spur  projecting  back  from 
the  reentrant  angle  formed  near  that  A'illage.  The  difference  in  the  contours 
of  these  two  portions  of  the  ridge  may  in  this  case  be  due  to  a  different 
position  in  reference  to  the  ice  margin,  the  portion  north  from  Haiupshire 
being  formed  at  the  extreme  margin  of  the  ice  sheet  and  the  portion  south 
fr(im.  Hampshire  at  some  distance  back  from  the  margin;  The  submarginal 
position  would  seem  to  be  a  sufficient  cause  for  the  smootlmess  of  contour. 

By  a  second  interpretation  the  Marengo  Ridge  is  made  later  than  the 
outer  ridge  of  the  Bloomington  system,  and  its  entire  length  considered  a 
marg'inal  accumulation.  Its  great  relief  above  the  outer  ridge  of  the 
Bloomington  systejn  at  Hampshire,  where  it  crosses  that  ridge,  so  strongly 
favors  this  interpretation  that  for  some  years  it  was  given  more  weight  by 
the  writer  than  other  interpretations,  though  the  absence  of  a  gravel  out- 
wash  on  the  west  border  of  the  portion  south  from  Hampshire  left  room  for 
doubt. 

A  third  interpretation  suggested  itself  when  revisiting  the  region  with 
a  view  to  reaching  a  more  satisfactory  conclusion  concerning  correlations. 
By  this  interpretation  the  outer  ridge  of  the  Bloomington  system  is  con- 
sidered to  pass  eastward  across  the  Marengo  Ridge  and  to  join  the  composite 
belt  lying  east  of  that  ridge.  The  portion  of  the  Marengo  Ridge  north  of 
Hampshire  would,  in  this  case,  have  stood  outside  the  ice  sheet,  while  the 
portion  south  of  Hampshire  would  have  been  overridden  by  it.  If  ihe 
weakness  of  the  outer  ridge  of  the  Bloomington  system  at  the  point  where 
it  connects  with  the  Marengo  Ridge  is  continued  eastward  some  difficulty 
would  Ije  experienced  in  tracing  it  over  the  more  bulky  and  more  sharply 
morainic  Marengo  Ridge.  The  abrupt  change  in  the  contour  of  the  Marengo 
Ridge  at  the  point  where  the  outer  ridge  of  the  Bloomington  system  con- 
nects with  it  seems  to  give  supjDort  to  this  interpretation,  as  well  as  to  the 
first  interpretation. 

Until  further  liglit  is  thrown  upon  the  subject,  the  value  of  each  of 
these  interpretations  nuist  remain  an  open  question.  At  present  the  writer 
is  unable  to  exclude  any  of  them,  nor  does  any  one  of  them  seem  decidedly 
better  sustained  b)-  the  phenomena  than  the  others. 


to 


COMPOSITE  MORAINIG  BELT  OF  NOETHERN^  ILLIl^fOIS.  297 

PORTION    OF   COMPOSITE    BELT    W^EST    OF    FOX    RIVER. 

GENERAL    FEATURES. 

Aside  from  the  Marengo  Ridge  just  described,  there  is  a  belt  from 
8  to  15  miles  in  width,  on  the  west  side  of  Fox  River,  in  McHeniy  and 
Kane  counties,  which  is  strongly  morainic,  there  being  only  a  few  small 
areas,  of  1  to  3  square  miles  each  (aside  from  marshes  and  swamps  included 
among  the  morainic  knolls),  in  which  the  surface  is  level.  The  belt  is 
more  elevated  on  the  west  border  than  in  the  A-icinity  of  Fox  River.  Its 
general  elevation  there  is  not  markedly  different  from  that  of  the  crest  of 
the  Marengo  Ridge.  At  the  State  line  it  rises  above  the  1,000-foot  contour, 
one  point  being  1,040  feet  above  tide  (Rolfe).  A  point  a  mile  south  of 
Alden  rises  above  1,000  feet.  Along  much  of  the  divide  between  the 
Kishwaukee  and  Fox  rivers,  from  the  State  line  southward  to  Crystal 
Lake,  the  altitude  is  above  950  feet.  In  southern  McHenr}^  County  and 
in  Kane  County  few  points  reach  950  feet,  but  much  of  the  divide  rises 
above  900  feet. 

Fox  River  enters  the  State  at  an  elevation  of  766  feet  (Rolfe)  and  falls 
about  25  feet  in  crossing  McHenry  County,  a  distance  by  course  of  stream 
of  over  30  miles.  In  Kane  County  its  descent  is  more  rapid,  there  being 
a  fall  of  125  feet  in  a  distance  no  greater  than  that  traversed  by  the  stream 
in  McHeni-y  County.  The  stream  is  in  the  midst  of  morainic  knolls  and 
ridges  as  far  south  as  Geneva,  beyond  which  it  has  a  plain  on  its  west 
border.  These  ridges  often  rise  abruptly  80  or  100  feet  above  the  level  of 
the  stream.  From  the  valley  of  Fox  River,  in  McHenry  and  Lake  counties, 
marshy  valley-like  tracts  extend  back  several  miles  to  the  west  and  2  to  3 
miles  to  the  east.  These  are  traversed  by  sluggish  streams  similar  to  the 
upper  com-se  of  the  river. 

Although  the  western  border  of  this  composite  belt  is,  on  the  whole, 
more  elevated  than  the  district  immediately  bordei'ing  Fox  River,  it  does 
not  present  so  rough  a  surface,  except  perhaps  in  central  Kane  County, 
where  a  few  square  miles  present  a  very  sharp  knob-and-basin  topography. 
If  a  strip  3  or  4  miles  wide  along  the  west  side  of  Fox  River  be  excepted, 
the  moraine  in  McHenry  County  presents  few  knolls  that  exceed  40  feet  in 
height.     The  great  majority  are  25  feet  or  less.     On  the  borders  of  Fox 


298  THE  ILLINOIS  GLACIAL  LOBE. 

River,  as  already  noted,  ridges  and  kuolls  in  some  cases  reach  a  lieig'ht  of 
80  or  100  feet.  Numerous  saucer-like  depressions  and  occasional  well- 
defined  basins  appear  in  all  parts  of  this  belt. 

In  northeastern  McHeniy  County  there  is  a  small  gi-avel  plain  known 
as  "English  Prairie,"  which  stands  about  100  feet  above  Fox  River  and 
occupies  perhaps  3  square  miles.  It  is  about  as  elevated  as  neighboring 
portions  of  the  moraine  and  is  bordered  by  morainic  knolls  and  ridges  on 
every  side.  In  the  vicinity  of  Crystal  Lake  and  Cary,  in  southeastern 
McHenry  County,  there  is  an  elevated  gravelly  tract  covering  several 
square  miles  in  which  the  surface  is  gently  undulating  and  more  subdued  in 
expression  than  neighboring  tracts  composed  more  largely  of  till.  The 
surface  is  not  so  level  as  in  English  Prairie.  Immediately  noiih  of  this 
gravelly  tract,  in  the  vicinity  of  Terra  Cotta,  there  are  broad  swampy  ti'acts  ■ 
nearly  as  low  as  Fox  River  which  separate  prominent  ridges  trending 
NNE.— SSW.  These  ridges  continue  prominent  throughout  the  greater 
part  of  Ts.  44  and  45,  R.  8  E. 

In  northern  Kane  County  there  are  small  plane  tracts  standing  nearly 
200  feet  above  Fox  River  which  have  been  di'ained  by  an  extensive  system 
of  ditches.  These  are  almost  completely  suiTOimded  by  morainic  knolls 
which  rise  20  to  40  feet  above  their  surface.  Some  of  these  knolls  near 
Gilbert  are  very  sharp.  In  the  vicinity  of  the  line  of  McHenry  and  Kane 
counties  Fox  River  is  bordered  on  each  side  by  morainic  tracts  nsing  150 
feet  or  more  above  the  level  of  the  stream,  and  there  is  scarcely  any  marshy 
land  on  its  borders  southward  from  this  line. 

From  the  vicinity  of  Elgin  southwestward  to  Lafox  there  is  a  belt  3 
or  4  miles  in  width  on  the  west  side  of  Fox  River  in  which  sharp  gravelly 
knolls  and  ridges  abound.  These  ridges  and  knolls  show  a  tendency  to 
arrangement  in  chains  trending  nearly  east-west,  or  about  at  right  angles 
with  the  trend  of  tlie  morainic  belt.  There  are,  however,  not  a  few  excep- 
tions to  this  trend,  some  ridges  being  nearly  in  line  with  the  morainic  belt. 
These  gravel  ridges  constitute  the  most  ])rominent  features  in  this  portion 
of  the  moraine,  many  of  them  being  30  to  40  feet  and  a  few  00  to  75  feet 
in  height.  The}'  often  rise  very  abruptly,  so  that  their  slopes  are  cultivated 
with  difficulty.  In  the  majority  of  cases  these  chains  of  laiolls  and  ridges 
folloM'  depressed  areas  standing  50  feet  or  more  below  the  general  level, 
and  the  present  di-ainage  lines  in  traversing  these  low  belts  wind  about 


COMPOSITE  MORAIlsIC  BELT  OF  NORTHERN  ILLINOIS.  299 

among-  the  g-ravellj  ridges.  In  a  few  cases  the  knolls  and  ridges  appear  on 
elevated  parts  of  the  district. 

In  Campton  Township  (T.  40,  R.  7  E.)  the  moraine  is  very  elevated, 
some  points  reaching  nearly  1,000  feet  above  tide,  and  presents  a  very  sharp 
knob-and-basin  topography.  It  has  probably  the  sharpest  knobs  and  the 
deepest  basins  found  in  the  State  of  Illinois.  The  highest  points  rise  about 
150  feet  above  the  border  districts  on  the  south  and  west  and  more  than  200 
feet  above  Fox  River.  Oscillations  in  level  of  75  feet  in  a  distance  of  30  to 
40  rods  are  not  uncommon,  and  several  beautiful  lakelets  of  an  acre  or 
more  each  are  sunk  deeply  in  the  midst  of  morainic  knolls  which  surround 
them.  This  very  strongly  morainic  topography  appears  at  the  point  where 
the  inner  belt  of  the  Bloomington  morainic  system  connects  with  the  com- 
posite belt  under  discussion.  It  also  terminates  the  prominent  portion  of 
the  composite  belt  so  far  as  developed  west  of  Fox  River. 

Upon  passing  southward  from  Campton  Township  a  miicli  lower 
country  is  entered  than  that  to  the  north,  the  descent  being  similar  to  that 
found  in  passing  southward  from  the  inner  border  of  the  Bloomington 
morainic  system  in  western  Kane,  Dekalb,  and  Lasalle  counties.  But 
instead  of  passing  into  a  plane-surfaced  tract,  siich  as  occurs  on  the  inner 
border  of  the  Blooiuington  S5^stem,  an  undulating  tract  is  entered,  which 
extends  south  to  the  border  of  Kendall  County  in  a  belt  several  miles  wide. 
This  tract  contains  a  few  very  prominent  knolls.  One,  known  as  Johnsons 
Mound,  situated  near  the  east  fork  of  Blackberry  Creek  in  sec.  15,  T.  39, 
R.  7  E.,  rises  about  150  feet  above  the  level  of  the  creek  and  covers  fully 
50  acres.  A  second  prominent  knoll,  known  as  Bald  Mound,  because  desti- 
tute of  trees,  is  situated  in  sec.  23  of  the  same  township.  It  rises  about  80 
feet  above  the  border  districts  and  covers  perhaps  100  acres.  It  is  elongated 
in  a  north-south  direction,  its  length  being  about  three  times  its  width.  Its 
southern  end  rises  abruptly,  but  at  the  north  it  descends  gradually  to  the 
gently  undulating  tract  which  borders  it.  A  third  knoll,  known  as  Wash- 
burn's Mound,  is  situated  between  the  other  two  in  sec.  14,  and  stands  about 
50  feet  above  the  bordering  country.  This  mound  is  also  elongated  north 
to  south,  and  has  a  length  of  one-half  mile  and  a  width  of  40  to  60  rods. 
This  mound  has  a  more  regular  border  than  the  other  two,  for  they  present 
spur-like  projections  which  extend  out  20  to  40  rods  beyond  a  regular 
border.     Aside  from  the  three  prominent  mounds  just  mentioned  the  knolls 


300  THE  ILLINOIS  GLACIAL  LOBE. 

seldom  reach  a  height  of  25  feet,  and  many  of  them  are  10  feet  or  less. 
The  Kane%'ille  esker  described  above  has  its  trough  mainly  within  this 
nndulatory  belt,  but  the  delta  lies  entirely  west  of  it  in  a  very  level  countr}-. 
There  are  occasional  narrow  sloughs  or  depressed  areas  10  or  15  feet  below 
the  general  level,  which  in  most  cases  have  connection  Avith  the  present 
drainage  lines.  The  upper  course  of  Blackben-y  Creek  is  through  a  series 
of  slightly  depressed  marshy  tracts  which  occur  among  the  low  knolls  of ' 
this  xindulatorr  belt.  The  undulations  are  maintained  as  far  south  as  the 
line  of  Kane  and  Kendall  counties,  the  southern  terminus  being  at  a  gravel 
plane  leading  down  Fox  River.  There  is  a  narrow  till  plain  between  this 
nndulatory  belt  and  Fox  River  from  Geneva  southward  similar  to  the  plain 
which  borders  it  on  the  west. 

STRUCTURE    OF    THE    DRIFT. 

The  drift  of  this  portion  of  the  composite  belt  is  much  more  variable 
in  structure  than  the  Marengo  Ridge.  On  nearly  ever}-  section  except  in 
the  gravelly  belts  above  noted  wells  have  shown  that  both  till  and  assorted 
material  are  present.  The  till  apparently  preponderates  over  the  assorted 
material,  for  the  latter  usually  occm-s  in  thin  beds.  In  the  gi-avel  plain 
known  as  English  Prairie  and  in  the  gravelly  belt  between  Crystal  Lake 
and  Fox  River  there  appears  to  be  httle  or  no  till  within  100  feet  of  the 
surface.  The  di-ift  is  mainly  gravel  and  cobble,  there  being  but  little  sand. 
In  places  fine  laminated  clays  appear  at  some  depth  beneath  till  and  grav- 
elly deposits.  The  Illinois  Central  Railway  exposes  such  beds  in  the  deep 
cuts  east  of  Plato  Center.  The  till  appears  to  be  oxidized  at  surface  to 
greater  depth  on  this  portion  of  the  composite  belt  than  on  the  Marengo 
Ridge,  a  feature  which  is  probably  attributable  to  the  greater  coarseness  or 
porosity  of  the  till,  for  it  can  not  be  older  than  the  Marengo  Ridge.  In 
some  cases  the  oxidation  extends  to  a  depth  of  50  feet  or  more.  However, 
the  till  is  not  everywhere  coarse  textured,  for  on  some  of  the  level  tracts 
among  the  raorainic  knolls  it  is  very  compact.  On  low  tracts  near  Terra 
Cotta,  in  eastern  McHenry  Count}-,  there  is  a  compact  silt  used  extensively 
for  tile  and  also  for  terra-cotta  ware.  At  several  other  places  the  silt  is 
used  for  tile. 

The  presence  of  1  juried  soils  at  great  depth  which  are  underlain  as  well 
as  overlain  b\-  till  is  a,  not  uncommon  feature.      In  some  cases  the  soils  are 


COMPOSITE  MORAINIO  BELT  OP  NORTHERN  ILLINOIS.  301 

referred  to  the  Peorian  interglacial  stage,  for  they  probably  occur  at  the 
junction  of  the  Wisconsin  and  lowan  drift  sheets.  But  it  is  possible  that  in 
many  cases  they  are  of  Sangamon  age  and  occur  at  the  junction  of  the 
lowan  and  Illinoian  sheets.  In  the  majority  of  cases  they  occur  in  the 
lower  23art  of  the  drift.  On  the  elevated  portions  they  seldom  are  found  at 
less  than  125  feet  from  the  surface,  and  in  one  instance  (at  Gilbert  station) 
a  soil  wasfoujid  at  180  feet.  The  drift  on  the  elevated  portions  apparently 
averages  not  less  than  200  feet.  On  the  lower  portions  of  the  belt,  in 
southern  Kane  County,  the  drift  is  correspondingly  tliinner.  The  buried 
soil  is  found  at  much  less  depth,  but  at  about  the  same  elevation  above  tide 
as  in  the  higher  portion.  The  occurrence  of  the  buried  soil,  its  depth  and  its 
relation  to  other  beds  of  the.  drift,  may  be  seen  by  reference  to  well  sections 
of  McHenry  and  Kane  counties  given  on  subsequent  pages. 

As  noted  above,  this  portion  of  the  composite  belt  abounds  in  knolls 
and  short  ridges  which  are  composed  largely  of  gravel.  These  are  largest 
and  most  numerous  along  the  inner  slope  adjacent  to  Fox  River,  but  are 
found  occasionally  on  the  elevated  parts  of  the  moraine — for  example,  near 
the  north  line  of  Kane  County.  These  ridges  occur  both  singly  and  in 
groups.  They  are  also  arranged  in  chains  or  narrow  belts.  They  present 
considerable  variation  in  structure.  The  majority  have  but  little  till  with 
the  sand  and  gravel,  but  some  present  a  large  amount  of  till  in  the  lower 
portion.  This  is  especially  true  of  those  on  the  elevated  portion  of  the 
moraine  in  northern  Kane  County.  In  several  cases  the  knolls  are  found 
to  have  a  body  of  coarse  gravel  and  cobble  at  their  summits  which  extends 
downward  in  a  funnel-shaped  mass  toward  the  center  of  the  hill.  In  other 
cases  the  central  portion  of  the  hill  is  composed  of  sand  and  the  gravel  and 
cobble  is  found  in  the  peripheral  portion.  A  knoll  in  sec.  14,  T.  42,  R  7  E., 
ojDened  extensively  for  gravel,  is  found  to  contain  alternations  of  till  and 
assorted  material.  The  till  apparently  forms  a  network  of  connections 
around  lenticular  masses  of  gravel.  In  most  instances  the  gravel  and  cob- 
ble is  found  to  extend  scarcely  as  low  as  the  base  of  the  knolls.  Borings 
have  sometimes  been  made  in  the  bottom  of  the  gravel  pits,  and  these  usu- 
ally penetrate  a  considerable  depth  of  oxidized  till.  Indeed,  the  oxidation 
appears  to  be  fully  as  deep  beneath  these  knolls  as  the  average  depth  of 
surface  oxidation  outside  the  knolls.  The  bedding  of  the  assorted  material 
is  seldom  horizontal,  but  cm-ves  and  dips  as  if  the  material  had  been  subject 


302  THE  ILLINOIS  GLACIAL  LOBE. 

to  much  disturbance  after  deposition.  In  this  respect  these  knolls  and 
ridges  differ  from  the  bedding  usually  displayed  by  eskers. 

Bowlders  are  found  in  moderate  number  over  all  parts  of  the  moraine. 
They  are  especially  abundant  in  a  belt  extending  fi-oni  Gilbert  station  north- 
ward to  the  vicinity  of  Crystal  Lake.  The  belt  is  widest  near  the  Kane- 
McHenrv  county  line,  having  there  a  width  of  about  4  miles.  There  is 
pi'obably  signilicauce  in  the  fact  that  this  bowlder  belt  borders  the  head  of 
the  Kishwaukee  gravel  plain,  which  was  an  avenue  of  discharge  for  the 
glacial  waters. 

The  bowlders  are  usually  crystalline  rocks  of  Canadian  derivation,  but 
there  are  also  present  large  limestone  blocks,  which  in  some  cases  will 
furnish  several  wagon  loads  of  building-  stone.  These  are  especially 
abundant  west  of  Elgin,  and  are  found  occasionally  farther  north,  in  both 
Kane  and  McHenry  counties.  They  are  apparentl}^  derived  from  the  ledges 
of  Lockport  (Niagara)  limestone,  which  underlie  the  disti'ict  immediately 
to  the  east  and  probably  extend  into  the  district  covered  by  this  moraine. 
In  some  cases  these  large  masses  of  limestone  have  led  the  residents  to 
suppose  that  the  rock  is  in  situ  and  that  extensive  quarries  might  be  opened 
by  the  removal  of  a  slight  amount  of  drift.  The  error  of  this  interpretation 
has  usually  been  discovered  upon  quarrying  a  few  loads  of  stone.  Wells 
west  of  Elgin,  in  the  neighborhood  of  these  limestone  blocks,  indicate  that 
the  drift  there  has  an  average  thickness  of  more  than  100  feet.  Whether 
the  sup]30sed  limestone  outcrop  in  eastern  McHenry  Count}",  mentioned  in 
the  Greology  of  Illinois,^  is  a  ledge  in  situ  or  a  transjjorted  block  similar  to 
those  just  mentioned  was  not  ascertained. 

CORRELATIONS. 

Satisfactory  correlations  of  this  portion  of  the  composite  belt  with  the 
more  clearly  differentiated  moraines  in  the  districts  to  the  south  have  not 
yet  been  established.  Two  quite  distinct  interpretations  have  been  suggested 
in  the  course  of  the  investigation.  By  the  first  interpretation  this  portion 
of  the  composite  belt  is  made  to  be  the  continuation  of  the  inner  part  of  the 
Bloomington  morainic  system,  which  connects  with  it  near  Elburn.  The 
very  strongly  morainic  tract  immediately  northeast  of  Elburu  ^^'ould,  in  this 
case,  be  situated  at  a  sharp  bend  or  reentrant  angle  in  the  ice  marg-iu,  and 


'  Vol.  IV,  pp.  131, 132. 


COMPOSITE  MORAINIC  BELT  OF  NORTHERN  ILLINOIS.  303 

this  may  account  for  its  greater  ruggedness.  The  uiidulator}-  tract  leading 
southward  from  this  sharply  morainic  portion  might  by  this  interpretation  be 
accounted  for  as  a  spur  extending  backward  from  the  sharp  bend  in  the 
margin.  The  bulk  of  the  Bloomington  system  is  not  greatly  different  from 
that  of  the  composite  belt  west  of  Fox  River  and  presents  lao  obstacles  to 
this  interpretation.  The  topography  of  the  composite  belt  is  much  sharper 
in  expression  than  that  of  the  Bloomington  system,  but  changes  of  topog- 
raphy have  been  found  to  occur  in  other  belts  to  as  marked  a  degree  as 
in  this  instance.  As  pointed  out  by  Chamberlin,  in  the  Third  Annual 
Report,  the  Kettle  moraine  changes  from  a  very  sharp  knob-and-basin 
topography  in  southern  Wisconsin  to  a  comparatively  smooth  swell-and-sag 
topography  in  northeastern  Illinois  and  northwestern  Indiana,  and  again 
assumes  a  sharji  knob-and-basin  topography  when  traced  into  Michigan. 

By  the  second  interpretation  this  portion  of  the  composite  belt  is  thrown 
into  the  late  Wisconsin  series  of  moraines  and  its  continuation  found  in  the 
bowlder  belts  and  feebly  developed  morainic  tracts  lying  outside  the  Valpa- 
raiso morainic  system  in  Kane,  Kendall,  Grundy,  and  Kankakee  counties. 
These  belts  can  be  traced  into  a  reasonably  close  connection  with  tlie 
southern  end  of  the  undulatory  belt  in  southern  Kane  County.  Tliere 
seems  to  be,  therefore,  no  formidable  gap  to  bridge  in  making  this  corre- 
lation. The  greatest  obstacle  to  the  interpretation  appears  to  be  found  in 
the  abrupt  change  in  bulk  which  the  moraine  presents  in  the  district  east 
of  Elburn.  From  this  point  southward  a  thickness  of  only  20  or  25  feet  is 
presented  by  the  moraine,  where  best  developed,  while  to  the  north  the 
thickness  averages  more  than  100  feet.  The  expression  also  is  much 
strono-er  north  than  it  is  south  from  this  line. 

Perhaps  by  combining  these  interpretations  a  solution  may  be  found. 
The  great  bulk  of  the  portion  north  from  Elburn  and  the  very  strong- 
expression  of  the  portion  immediately  northeast  of  Elburn  may  be  a  result 
of  the  invasion  which  formed  tlie  Bloomington  morainic  system.  At  the 
late  Wisconsin  invasion  this  region  may  have  been  partially  overridden  by 
the  ice,  but  without  greatly  modifying-  its  appearance  and  without  deposit- 
ing a  greater  amount  of  drift  than  is  found  in  the  gently  undulatory  belt  in 
southern  Kane  County  and  the  feeble  moraines  in  the  district  to  the  south. 
In  this  case  the  gently  undulating  tract  in  southern  Kane  County  may  be 
largely  the  result  of  the  late  Wisconsin  invasion,  though  the  interpretation 


304  THE  ILLmOIS  GLACIAL  LOBE. 

that  it  is  a  spur  from  the  reentrant  angle  in  the  Blooniington  system  need 
not  be  set  aside. 

The  Kaneville  esker  Hes  mainly  within  the  limits  of  this  undulatory 
belt  and  seems  to  have  been  formed  at  as  late  a  date.  Its  western  end, 
together  with  the  delta,  extends  beyond  the  line  of  the  bowldery  tracts 
referred  to  the  late  Wisconsin  invasion.  This  fact  seems  to  throw  the  bal- 
ance of  evidence  in  favor  of  tlie  correlation  with  the  Bloomington  system. 
Furthermore,  the  Kaneville  esker  seems  to  be  a  part  of  the  series  of  g-ravelly 
knolls  and  ridges  above  mentioned  which  are  developed  along  the  inner 
border  of  the  Bloomington  morainic  system  in  the  district  to  the  west.  It 
is  possible  that  chains  of  gravelly  knolls  and  ridges  which  lead  westward 
from  Fox  River  Valley  in  northern  Kane  County  into  the  higher  portions 
of  the  moraine  were  formed  at  the  same  time  as  this  esker  and  under  similar 
conditions.  The  prominent  knolls  which  occur  in  the  midst  of  the  gently 
undulating  belt — Johnson's  Mound,  Ball  Mound,  and  Washburn's  JMound — 
mav  also  be  included  in  the  same  categ'ory.  They  appear  to  be  composed 
largely  of  gravel,  though  their  structure  is  known  only  from  two  well  sec- 
tions on  their  higher  parts  and  slight  excavations  on  their  borders. 

PORTION  OF  COMPOSITE  BELT  EAST  OF  FOX  RIVER. 
DISTRIBUTION   AKD   CONNECTIONS. 

From  the  ^dcinity  of  Elgin  northward  to  the  Wisconsin  line  the  valley 
of  Fox  River  alone  separates  a  morainic  tract  on  the  east  from  one  on  the 
west  side  of  the  river,  and  throughout  much  of  this  interval  the  stream  wnnds 
about  through  lakes  and  marshes  among  morainic  knolls  without  forming  a 
well-defined  valley.  Southward  from  Elgin  the  composite  belt  separates 
into  distinct  moraines,  between  Avhieh  are  plane  tracts.  One  of  these 
moraines,  called  the  Valparaiso,  swings  around  the  head  of  Lake  Michigan; 
another,  called  the  Marseilles,  follows  nearly  the  east  bluft'  of  Fox  River 
south  and  west  to  the  Illinois  River.  As  already  noted,  a  weak  morainic 
system  of  late  Wisconsin  age  leads  southward,  and  the  Bloomington  system 
southwestward,  from  the  ])ortion  of  the  composite  belt  west  of  Fox  River. 

The  equivalency  of  the  Valparaiso  morainic  system  to  the  eastern 
portion  of  this  composite  belt  is  established  beyond  doubt.  Probably  it 
should  include  all  uf  the  composite  belt  nortli  of  Elgin  on  the  east  side  of 


COMPOSITE  MOKAINIO  BELT  OF  JS^ORTHEEN  ILLINOIS.  305 

Fox  River,  and  possibly  it  also  iu eludes  a  small  part  west  of  this  stream. 
It  may  extend  as  far  west  as  the  east  border  of  English  Prairie,  at  the  State 
line,  and  may  embrace  the  tract  between  Fox  River  and  Crystal  Lake 
outlet,  farther  south. 

The  equivalent  of  the  Marseilles  morainic  system  in  this  composite 
belt  is  not  satisfactorily  determined.  From  northern  Kendall  County  north- 
ward it  appears  to  have  been  overridden  to  some  extent  by  a  later  advance 
of  the  ice,  and  is  perhaps  completely  concealed  by  the  later  deposits  within 
this  composite  belt. 

The  portion  of  the  composite  belt  east  of  Fox  River  has  a  width  rang- 
ing from  6  or  7  miles  at  the  State  line  to  about  15  miles  at  the  south  line  of 
Lake  and  McHenry  counties.  Between  these  lines  it  is  mainly  in  Lake 
County,  but  includes  a  narrow  strip  in  eastern  McHenry  County.  From 
the  south  line  of  these  counties  southward  to  Elgin  it  lies  mainly  in  Cook 
County,  but  includes  the  east  border  of  northern  Kane  County  and  main- 
tains a  width  of  14  to  15  miles.  This  is  about  the  width  of  the  Valparaiso 
system  farther  south. 

GENEEAL   FEATURES. 

The  general  elevation  of  this  portion  of  the  composite  belt  is  lower 
than  in  the  portion  west  of  Fox  River,  being  but  little  more  than  800  feet 
above  tide.  The  highest  points  are  found  in  southern  Lake  and  northwest- 
ern Cook  counties,  and  they  rise  but  little  above  900  feet.  One  of  these, 
just  east  of  the  village  of  Volo,  stands  913  feet,  and  one  in  the  northwest 
comer  section  of  Cook  County  910  feet,  as  determined  by  the  barometric 
survey  under  Professor  Rolfe.  There  are,  however,  but  few  other  points 
rising  above  850  feet. 

There  is  a  well-defined  ridge-like  crest  standing  20  to  40  feet  higher 
than  border  tracts  and  having  a  width  of  about  one-half  mile  which  leads 
southward  with  a  somewhat  winding  course  through  western  Lake  and 
northwestern  Cook  counties,  forming  the  water  parting  between  Fox  and 
Des  Plaines  rivers.  East  from  this  crest  line  there  are  only  gentle  swells, 
seldom  more  than  15  feet  in  height,  among  which  are  occasional  ponds  and 
small  lakes.  This  district  presents  a  slope  which  descends  eastward  at  the 
rate  of  20  to  40  feet  to  the  mile  as  far  as  the  Des  Plaines  Valley.  West 
from  the  crest  line  the  surface  is  much  more  varied,  there  being  tracts 
."MON  xxxviii 20 


306  THE  ILLINOIS  GLACIAL  LOBE. 

covering  a  few  square  miles  in  which  a  sharp  knob-aud-basin  topography  is 
developed,  around  which  are  gently  undulating  tracts,  such  as  occm-  on  the 
east  slope.  There  are  also  extensive  marshes  west  of  this  crest,  and  the 
drainage  is  generally  less  perfect  than  on  the  east  slopes.  Lakes  abound  in 
Lake  County  on  both  the  west  and  the  east  slopes.  They  range  in  size 
from  an  area  of  several  square  miles  down  to  an  acre  or  less.  They  are 
usually  bordered  wholly  or  in  part  by  knolls  and  ridges  which  rise  10  to 
50  feet  above  their  surface.  In  some  cases  extensive  marshes  border  one 
or  more  sides  of  the  lakes.  These  lakes,  with  their  bordering  hills  dotted 
with  groves,  add  greatly  to  the  beauty  of  the  scenery.  The  lakes  and  also 
basins  become  rare  soiithward  in  Cook  County.  The  few  which  occur  are 
very  small  and  shallow. 

THICKNESS   OF   DRIFT. 

Records  of  several  deep  boring-s  were  obtained  which  give  an  average 
thickness  of  about  200  feet  of  drift.  Six  borings  failed  to  reach  rock  at  an 
average  depth  of  about  250  feet,  one  of  them  being  315  feet.  As  these 
borings  are  widely  distributed,  it  seems  probable  that  the  general  level  of 
the  rock  surface  is  fully  200  feet  below  the  drift  sm-face.  The  underlying 
rock  is  limestone  and  presents  a  very  uneven  surface.  The  well  borings 
indicate  that  vallej^s  had  been  cut  to  depths  of  200  feet  or  more  prior  to  the 
di-ift  deposition.  Hence  borings  in  the  lines  of  these  valleys,  when  located 
on  high  parts  of  the  moraine,  probably  would  encounter  fully  400  feet  of 
di'ift.  The  thickness  of  each  of  the  several  drift  sheets  here  present  has  not 
been  worked  out  so  fully  as  in  some  other  localities,  but  the  drift  of  Wisconsin 
age  apparently  averages  not  less  than  100  feet  in  depth,  and  may  average 
150  feet. 

STRUCTURE   OF   THE   DRIFT. 

The  upper  portion  of  the  drift  to  a  depth  of  100  to  150  feet  consists 
mainly  of  till.  The  till  is  usually  oxidized  at  surface  to  a  depth  of  10  or 
15  feet,  beneath  which  it  presents  a  blue-gray  color.  It  is  also  generally 
soft  and  fresh,  and  seems  to  be  referable  to  the  Wisconsin,  though  it  may 
also  include  the  lowau.  At  greater  depths  than  100  to  150  feet  borings 
encounter  either  a  hard  gray  till  tinged  with  brown,  probably  Illinoian,  or 
beds  of  sand  and  gravel,  or  an  alternation  of  till  with  sand  and  gravel. 
Wells  near  Lake  Zurich  have  in  several  instances  encountered  thick  beds  of 


THE  MARSEILLES  MOKAIIfE.  307 

fine  sand  below  the  till,  setting  in  at  100  to  140  feet  and  extending  to  250 
or  300  feet.  At  Barrington,  and  for  several  miles  southwest,  wells  often 
enconnter  a  hard  till  at  100  to  160  feet  which  contains  very  little  sand. 
In  the  vicinity  of  Ivanhoe  and  Wauconda  wells  pass  thi-ough  alternations 
of  sand  and  gravel  with  hard  till  after  leaving  the  sheet  of  soft  till. 

In  southern  Lake  and  northwestern  Cook  counties  the  sheet  of  soft  till 
is  generally  a  poor  source  for  strong  wells,  such  as  are  required  on  dairy 
farms,  though  wells  adequate  for  household  use  may  usually  be  obtained  at 
convenient  depths.  In  the  northern  part  of  Lake  County  strong  wells  are 
often  obtained  without  reaching  the  bottom  of  the  Wisconsin  drift  sheet. 
The  greater  amount  of  sand  and  gravel  found  in  the  older  di-ift  sheets  has 
led  to  the  sinking  of  many  weUs  to  these  sheets  at  depths  of  150  feet  or 
more.     Further  data  are  given  in  the  detailed  discussion  of  wells. 

There  are  but  few  gravel  knolls  in  either  Lake  County  or  Cook 
County,  but  such  knolls  are  not  rare  on  the  borders  of  Fox  River  in  eastern 
Kane  and  McHenry  counties.  Knolls  composed  mainly  of  till  have  in 
some  cases  pockets  of  gravel  at  or  near  the  surface,  which  supply  material 
for  wagon  roads.  There  are  few  localities  west  of  the  crest  where  gravel 
may  not  be  conveniently  obtained,  but  east  of  the  crest  it  is  not  so  well 
distiibuted. 

Surface  bowlders  occur  in  moderate  numbers  over  all  of  tliis  district. 
They  are  nearly  all  crystalline  rocks  of  distant  derivation,  there  being  very 
few  limestone  or  local  rocks.  The  till  is  thickly  set  with  limestone  rocks 
as  well  as  with  those  of  distant  derivation. 

SECTION  V.     THE  MARSBIIiLES  MOBAINE, 

DISTKIBUTION. 

This  moraine  next  succeeds  the  Bloomington  morainic  system  in  the 
Wisconsin  series.  The  name  is  taken  from  the  village  of  Marseilles,  situated 
at  the  point  where  the  Illinois  Eiver  cuts  thi-ough  the  moraine. 

The  moraine  is  readily  traced  as  far  north  as  South  Elgin,  4  miles 
south  of  the  city  of  Elgin,  where  it  is  lost  in  the  composite  belt  just  dis- 
cussed. For  about  25  miles  south  from  South  Elgin  it  is  combined  with  a 
till  ridge  called  the  Minooka  Ridge,  and  follows  the  east  side  of  Fox  River 
closely,  past  St.  Charles,  Greneva,  Batavia,  and  Aurora,  the  eastern  parts  of 


308  THE  ILLINOIS  GLACIAL  LOBE. 

these  cities  occupying  its  outer  face.  There  is  usually  but  a  single  crest, 
and  it  follows  nearh'  the  county  line  between  Kane  and  Dupage.  The 
width  of  the  belt  is  2  or  3  miles.  The  combined  belt  continues  about  6 
miles  farther  south  than  Aurora,  along  the  line  of  Will  and  Kendall  coun- 
ties, lea\4ug  a  strip  2  or  3  miles  wide  between  the  river  and  the  moraine. 
The  Marseilles  moraine  there  swings  abruptly  westward,  coming  to  the 
river  bluff  between  Oswego  and  Yorkville,  while  the  Minooka  Ridge  con- 
tinues southward  to  the  head  of  the  Illinois  River.  The  Marseilles  moraine 
follows  neai'ly  the  southeast  bluff  of  Fox  River  to  the  mouth  of  the  stream, 
its  outer  border  being  nowhere  more  than  4  miles  and  usually  less  than  1 
mile  from  the  stream.  The  width  in  Kendall  County  is  only  2  or  3  miles, 
but  increases  to  5  or  6  miles  in  northeastern  Lasalle  County,  near  the  north 
bluff  of  the  IlHnois  River. 

At  tlie  Illinois  Valley  the  moraine  changes  abruptly  from  a  south- 
southwest  to  a  south-southeast  course.  Its  south-southeast  course  is  mam- 
tained  in  a  belt  3  to  5  miles  wide  passing  tlu'ough  southeastern  Lasalle  and 
northern  Li^angston  counties.  In  the  latter  county,  as  above  noted,  it  is 
closely  associated  with  Farm  Ridge,  a  weak  inner  ridge  of  the  Bloomington 
system.  In  the  vicinity  of  Odell  the  moraine  swings  around  eastward,  and 
near  the  line  of  Livingston  and  Ford  counties  takes  a  course  north  of  east, 
occupying  in  its  curving  portion  a  width  of  8  or  10  miles.  This  course  is 
maintained  across  northern  Ford,  northwestern  Iroquois,  and  southern  Kan- 
kakee counties,  to  the  ^^cinity  of  Ste.  Anne,  where  it  changes  to  southeast. 
From  northern  Ford  County  to  this  point  it  has  a  width  of  3  to  5  miles.  The 
southeast  com-se  is  maintained  to  the  vicinity  of  the  State  line  northeast  of 
Donovan.  Here  this  moraine  meets  the  Iroquois,  a  moraine  of  the  coalesced 
Erie-Saginaw  lobe.  Its  relations  to  that  moraine  are  still  obscm-e,  though 
the  courses  of  the  two  moraines  seem  to  be  nearly  coincident  in  Newton  and 
Jasper  counties,  Indiana.  Its  width  before  connecting  with  that  moraine  is 
1  to  2  miles.  The  combined  moraine  has  a  width  of  3'  to  6-  miles  and  is 
traceable  as  far  as  Medaryville,  in  Pulaski  County,  Indiana,  beyond  which 
it  seems  either  to  die  out  or  to  be  concealed  beneath  the  "Lake  Kankakee" 
sand  rido-es.  Possibly  this  combined  moraine  constitutes  an  interlobate 
belt,  but,  as  indicated  below  (pp.  318,  327),  it  seems  more  probable  that 
it  is  a  result  of  two  advances  differing  in  date  as  well  as  direction. 


THE  MARSEILLES  MORAINE.  309 

RANGE    IN    ALTITUDE. 

The  Marseilles  moraine  displays  very  little  range  in  altitude.  The 
crest  varies  scarcely  25  feet  from  the  750-foot  contour,  and  the  lower  parts 
of  the  moraine  stand  near  the  650-foot  contour.  Tlu-oughout  much  of  its 
course  the  650-foot  contour  follows  approximately  the  outer  border  of  the 
moraine.  The  inner  border  is  somewhat  higher,  but  as  a  rule  falls  below 
700  feet. 

RELIEF. 

The  above  statements  concerning  range  in  altitude  may  be  readily 
applied  in  reference  to  the  relief  of  the  moraine.  On  the  outer  border  it 
averages  about  100  feet;  it  is  seldom  less  than  50  feet  and  in  places  reaches 
125  feet.  The  relief  on  this  border  is  least  in  the  northern  and  the  eastern 
portion  of  the  belt,  in  places  being  50  feet  or  less.  The  middle  portion, 
except  where  combined  with  the  weak  inner  ridge  of  the  Bloomington  sys- 
tem (Farm  Ridge),  has  a  general  relief  of  75  to  100  feet  or  more.  On  the 
inner  border  the  relief  seldom  exceeds  50  feet,  and  for  a  few  miles  at  the 
north  scarcely  exceeds  25  feet. 

SURFACE   CONTOURS. 

Throughout  much  of  its  course  the  Marseilles  moraine  has  a  well-defined 
crest,  and  this,  as  a  rule,  constitutes  a  water  parting.  North  of  the  Illinois 
River  it  separates  the  tributaries  of  Fox  River  from  those  of  Dupage  River, 
Au  Sable  Creek,  and  Nettle  Creek.  South  of  the  Illinois  it  separates  trib- 
utaries of  the  Vermilion  River  from  those  of  Mazon  Creek  and  Kankakee 
River.  In  eastern  Illinois,  however,  it  does  not  constitute  an  important 
water  parting,  being  crossed  by  the  Iroquois  River;  and  in  western  Indiana 
it  is  crossed  by  tributaries  of  that  river.  The  crest  is  sharpest  for  a  few 
miles  in  the  central  part  of  Kendall  County,  south  and  southwest  of  York- 
ville,  where  it  presents  a  narrow  ridge  standing  30  to  40  feet  or  more  above 
bordering  portions  of  the  moraine.  Usually  the  crest  is  a  broad,  gently 
undulating  ridge  1  or  2  miles  in  width.  Along  the  crest,  as  well  as  on  the 
slopes,  there  are  saucer-like  depressions  containing  water,  except  in  seasons 
of  drought,  and  often  occupied  by  clumps  of  willows.  The  swells  are  usually 
low,  seldom  exceeding  20  feet  in  height,  and  have  gentle  slopes.  However, 
in  parts  of  Livingston  County,  southeast  of  Odell,  the  swells  in  some  cases 
reach  a  height  of  50  feet  above  sloughs  inclosed  among  them.     There  is 


310  THE  ILLINOIS  GLACIAL  LOBE. 

also  a  group  of  prominent  knolls  in  the  ^-icinity  of  the  line  of  Kankakee 
and  Iroquois  counties,  south  of  Hersher.  Some  of  these  reach  a  height  of 
about  75  feet.  At  the  point  where  the  course  of  the  moraine  changes  from 
east  of  north  to  southeastward,  near  Ste.  Anne,  there  is  a  -s-ery  prominent 
gi'oup  of  knolls,  called  Mount  Langum,  standing  75  to  100  feet  above 
bordering  tracts  on  the  north.  These  groups  of  prominent  knolls  have, 
however,  a  combined  area  of  but  a  few  square  miles.  Toward  the  inner 
border  tlii-oughout  the  entire  length  of  the  moraine  the  swells  gi-adually 
decrease  in  height  and  become  less  frequent,  until  they  can  not  be  distin- 
guished fi'om  the  gentle  undulations  of  the  till  plain,  which  are  commonly 
5  or  6  feet  in  height.  In  a  few  places,  aside  from  those  noted  above,  a 
somewhat  sharp  knob-and-basin  topography  is  developed.  The  most  con- 
spicuous development  is  in  Kendall  County  along  the  sharp  crest,  and  this 
tj^e  of  topog-raphy  is  characteristic  of  much  of  the  crest  in  that  county. 
The  knobs  seldom  exceed  25  feet  in  height;  but  as  they  cover  only  2  or  3 
acres  each,  they  are  much  sharper  than  the  majority  of  the  knolls.  The 
basins  are  shallow,  saucer-like  depressions.  It  is  worthy  of  note  that  the 
portions  of  the  moraine  having  sharpest  expression  are  usuallv  covered 
with  forest.  Possibly  the  protection  afforded  b}^  forest  growth  is  partiallv 
responsible  for  the  sharper  contours,  but  it  seems  liardly  probable  that  the 
difference  in  contour  in  forest  and  prairie  can  be  entu-ely  due  to  this 
protection. 

The  outer  margin  of  the  moraine  often  extends  out  in  spur-like  pro- 
jections a  mile  or  more  beyond  a  regular  border,  and  usually  where  streams 
emerge  the  margin  is  indented  an  equal  or  even  greater  amount.  These 
spurs  slope  down  much  less  abruptly  from  the  morainic  crest  than  the  tracts 
between  them,  thus  giving  the  appearance  of  low  ridges  running  out  from 
the  crest  nearly  at  right  angles  to  its  course.  The  indentations  at  the  places 
where  streams  emerge  are  not  referable  to  erosion  by  the  present  streams, 
but  are  in  all  probability  due  to  the  removal  of  material  by  streams  issuing 
from  the  ice  sheet. 

There  are  occasional  breaks  or  uaiTOw  gaps  interrupting  the  crest. 
One  about  4  miles  east  of  Yorkville,  about  75  feet  in  depth  and  one-foui-th 
to  one-half  mile  in  width,  passes  entirely  acro.ss  the  moraine,  permitting 
di-ainage  from  the  inner-border  plain  to  pass  through  the  moraine  to  Fox 
River.     Another  gap  fully  as  lai-ge  is  found  in  tlie  southwest  corner  of 


THE  MAESEILLES  MORAINE.  3n 

Kendall  County  and  is  represented  on  the  Marseilles  topographic  sheet.  A 
water  parting  occurs  in  this  valley-Hke  gap  at  the  inner  border  of  the 
moraine  near  the  line  of  Grundy  and  Kendall  counties.  It  stands  only  640 
feet  above  tide,  while  neighboring  portions  of  the  moraine  on  the  north  and 
west  are  about  100  feet  higher.  About  6  miles  southwest  from  this  gap 
there  is  a  shallower  one  in  which  the  water  parting  is  690  feet,  or  40  to  60 
feet  below  neighboring  portions  of  the  morainic  crest.  At  the  Illinois 
Valley  the  moraine  is  interrupted  by  a^  gap  about  1^  miles  in  width.  It 
stands  675  to  700  feet  above  tide  at  the  south  bluif  and  650  to  675  feet  at 
the  nofth  bluff.  The  broad  bottom  of  the  valley  stands  only  about  600 
feet;  but  this,  as  shown  below,  has  been  lowered  by  the  "Chicago  Outlet." 
These  gaps,  like  the  indentations,  seem  referable  to  streams  issuing  from 
the  ice  sheet  during  the  formation  of  the  moraine,  and  perhaps  also  during 
the  withdrawal  of  the  ice  from  the  plain  on  the  east. 

In  eastern  Livingston  and  northern  Ford  counties  the  main  ridge  lies 
near  the  north  border  of  the  belt.  Outside  of  it,  extending  nearly  to  the 
east  fork  of  Vermilion  River  (a  distance  of  about  6  miles),  there  is  an 
undulatory  tract  probably  of  morainic  character.  The  surface  of  much  of 
this  tract  is  fully  as  undulatory  as  on  the  main  part  of  the  moraine,  and 
stands  nearly  as  high  as  the  crest  of  the  moraine.  Plane  tracts  one-half 
mile  to  a  mile  or  more  in  width  and  25  to  40  feet  in  depth  extend  north 
from  the  east  fork  of  Vermilion  River  nearly  to  the  crest  of  the  moraine, 
greatly  interrupting  the  contiimity  of  the  undulatory  tract  just  noted  and 
giving  the  appearance  of  spurs  leading  out  to  the  south.  There  is,  however, 
at  the  east  a  well-defined  crest  in  this  outer  belt  with  a  trend  approximately 
parallel  with  that  of  the  main  crest.  This  suggests  the  interpretation  that 
the  moraine  consists  of  a  double  ridge  in  this  region,  and  that  its  outer  ridge 
has  been  imperfectly  developed  or  greatly  eroded.  If  the  imperfection  is 
due  to  erosion,  it  seems  necessary  to  restrict  the  eroding  agency  chiefly  to 
water  escaping  from  the  ice  sheet,  for  there  has  been  apparently  but  httle 
postglacial  erosion  in  this  locality. 

THICKNESS   OP   THE  DRIFT. 

The  thickness  of  the  drift  along  the  Marseilles  moraine  has  a  known 
range  from  less  than  100  feet  up  to  360  feet.  In  eastern  Kane  and  western 
Dupage  counties  the  thickness  along  the  crest  is  generall}-  100  to  150  feet. 


312  THE  ILLINOIS  GLACIAL  LOBE. 

Ill  Kendall  County  it  has  a  known  range  from  100  feet  to  fnlly  200  feet. 
In  Lasalle  County  the  well  records  show  a  range  from  about  100  up  to 
285  feet.  In  Li%angston  County  the  range  is  still  greater,  the  distance  to 
rock  varying  from  100  to  360  feet.  Along  the  line  of  Kankakee  and 
Iroquois  counties  it  deci'eases  from  about  160  feet  at  the  west  to  only  60 
feet  at  Ste.  Anne,  but  wells  between  Ste.  Anne  and  the  State  line  penetrate 
80  to  150  feet  of  drift. 

The  greater  part  of  the  drift?  appears  to  be  referable  to  the  Wisconsin 
drift  sheets.  The  older  sheets  are  seldom  entered  at  less  than  100  feet 
along  the  crest  of  the  moraine,  and  in  some  wells  a  fresh-looking  drift 
(Wisconsin)  is  reported  to  extend  to  a  depth  of  160  feet.  The  diift  refer- 
able to  the  invasion  which  formed  the  Marseilles  moraine  probably  about 
equals  in  thickness  the  measure  of  the  relief  of  the  moraine,  which,  as 
noted  above,  is  50  to  125  feet. 

STRUCTURE   OF   THE   DRIFT. 

The  Marseilles  moraine  consists  mainly  of  a  sheet  of  blue  till  which 
contains  only  a  moderate  amount  of  coarse  rock  materials.  A  few  low 
gravelly  knolls  occur  in  some  of  the  recesses  on  the  outer  border  of  the 
moraine  in  Kane,  Kendall,  and  northern  Lasalle  counties.  The  sharp 
knolls  south  of  Hersher,  and  the  prominent  group  of  knolls  known  as  j\Iount 
Laugum,  near  Ste.  Anne,  are  composed  largely  of  gravelly  material. 
These  constitute  the  chief  instances  of  the  occun-ence  of  gravelly  knolls 
along  the  entire  length  of  the  belt.  There  are  often  small  pockets  or  thin 
beds  of  sand  and  gravel  inclosed  in  the  sheet  of  till,  which  afford  a  supply 
of  water  for  the  shallow  wells.  These  seldom  afford  a  sufHcient  amount  of 
water  for  dairying  or  stock  raising,  the  supply  for  these  purposes  being 
obtained  either  from  the  older  sheets  of  drift  or  from  the  imderl)-ing  rock. 

This  moraine  carries  very  few  sui-face  bowlders,  there  being  scarcely 
enough  to  supply  the  needs  of  the  residents  for  foundations  of  buildings 
and  construction  of  Ijridge  culverts.  In  one  locality,  however,  east  of 
Yorkville,  the  moraine  is  crossed  by  a  bowlder  belt  which  apparently 
pertains  to  a  later  advance  of  the  ice,  since  the  bowlder  belt  does  not  follow 
the  moraine  but  passes  southward  across  the  inner-border  plain,  as  indicated 
later  (pp.  325-326). 


THE  MARSEILLES  MOEAINE. 


313 


The  depth  of  surface  oxidation  in  tliis  moraine  is  less  than  on  any  other 
moraine  of  the  Wisconsin  series  within  the  area  under  discussion.  In  Liv- 
ingston County  the  blue  till  is  commonly  entered  at  4  to  6  feet,  and  in 
places  at  even  less  depth.  The  oxidized  till,  therefore,  has  scarcely  half 
•the  depth  usually  found  in  the  Wisconsin  drift  sheets.  The  slight  depth  of 
surface  oxidation  is  probably  attributable  to  the  compactness  of  the  till, 
which  is  nearly  impervious  to  water.  It  can  not  be  attributed  to  flatness 
of  surface,  because  the  depth  of  oxidation  is  found  to  be  very  slight  on 
undulating  as  well  as  level  portions  of  this  drift  sheet. 

The  sections  of  many  wells  obtained  along  this  moraine  and  on  the 
inner  border  are  presented  in  the  discussion  of  wells  (Chapter  XIV)  in  the 
counties  traversed  by  the  moraine.  These  serve  to  indicate  the  gi'eat 
preponderance  of  till  over  assorted  material  in  the  portion  of  the  drift 
referable  to  the  Marseilles  moraine.  They  also  serve  to  indicate  the  rela- 
tive proportions  of"  till  and  assorted  material  in  the  sheets  of  older  drift 
imderlying  the  Marseilles  and  other  Wisconsin  drift  sheets. 


CHARACTEE   OF   THE   OTJTWASH. 


Along  Fox  River,  in  Kane  and  Kendall  counties,  just  outside  the  Mar- 
seilles moraine,  there  is  a  belt  of  coarse  gravel.  In  places  the  deposit  lies 
mainly  on  the  same  side  of  the  river  as  the  moraine,  but  generally  it  is  on 
the  opposite  side.  At  Batavia  it  is  chiefly  on  the  west  side,  at  Aurora  on 
the  east  side,  and  at  Yorkville  on  the  west  side.  At  Millbrook  and  at  Mill- 
ington  the  larger  part  of  the  gravel  is  on  the  east  side  of  the  river.  The 
belt  of  gravel  extends  but  a  short  distance  below  Millington,  the  valley 
below  that  point  being  cut  in  till  and  rock  strata.  The  origin  of  this  belt 
of  gravel  has  not  been  decided.  Possibly  it  is  referable  to  the  invasion 
which  formed  the  Marseilles  moraine,  but  quite  as  probably  it  should  be 
referred  to  the  later  advances  of  the  ice  sheet,  during  which  the  Marseilles 
moraine  was  partially  ovei-ridden.  The  gravel  is  so  extensive  in  Kane  and 
Kendall  counties  and  so  small  in  amount  farther  down  Fox  River  as  to  sua-- 
gest  the  interpretation  that  it  forms  an  extensive  delta  in  northern  Kendall 
and  southern  Kane  counties,  and  that  free  drainage  or  escape  of  the  waters 
down  Fox  River  had  not  been  established. 

In  the  vicinity  of  the  Illinois  River  there  ai-e  indications  of  a  lake-like 
expansion  of  outflowing  waters  whose  borders  are  found. iu  the  sand  ridges 


314  THE  ILLINOIS  GLACIAL  LOBE. 

discussed  on  a  preceding  page  (p.  288).  The  Illinois  Valley,  therefore, 
appears  to  have  been  unopened  along  the  section  between  the  Marseilles 
moraine  and  the  inner  moraine  of  the  Bloomington  series. 

In  eastern  Illinois  the  basin  now  drained  by  the  Iroquois  River  north- 
ward to  the  Kankakee  would  have  been  prevented  from  discharging  in  this 
direction  by  the  ice  sheet.  It  is  probable,  as  noted  above,  that  the  outlet 
from  this  district  was  westward  across  the  rim  of  the  basin  in  northern  Ford 
County  to  the  east  fork  of  Vermilion  River.  As  this  rim  stands  somewhat 
higher  than  the  northern  part  of  the  basin,  it  may  be  supposed  that  the  ice 
sheet  terminated  in  a  shallow  body  of  water.  The  only  outwash  found 
along  the  outer  borders  of  the  moraine  in  this  district  consists  of  tine  sand 
and  silt  forming  a  thin  coating  on  the  surface  of  the  till.  ^'^Hiether  this  is 
an  outwash  from  the  ice  at  the  time  of  the  formation  of  the  ]\Iarseilles 
moraine  or  is  of  later  date  can  scarcely  be  determined  in  the  present  stage 
of  investigation.  Studies  in  western  Indiana  indicate  that  a  lake  may  have 
occupied  this  region  for  some  time  subsequent  to  the  retreat  of  the  ice  from 
the  Marseilles  moraine,  and  this  silt-and-sand  deposit  may  be  a  product  of 
the  later  stage  of  the  lake. 

In  eastern  Livingston  County  there  may  have  been  a  fair  escape  for 
the  water  southward  into  the  East  Fork  of  Vermilion,  though  this  is  not 
fully  demonstrated. 

Reviewing  the  above  statements,  it  appears  that,  with  the  possible 
exception  of  the  northern  portion  of  the  moraine  in  Kane  and  northern 
Kendall  counties,  the  ice  sheet  was  bordered  extensively  by  lakes,  which 
prevented  a  vigorous  outwash.  But  these  lakes  were  so  shallow  as  to  inter- 
fere in  no  way  with  the  building  up  of  a  bulky  moraine.  They  seem  also 
to  have  allowed  the  waters  escaping  from  the  ice  sheet  to  form  the  gaps 
and  indentations  in  the  moraine,  noted  above.  If  these  were  formed  either 
by  water  escaping  from  the  ice  while  it  overhung  the  ridg-e,  or  at  a  later 
date  from  a  lake  held  on  the  east  side  of  the  ridge  (the  only  probable  agen- 
cies yet  recognized),  the  existence  of  lakes  in  the  outer  border  district  may 
seem  questionable.  This  seeming  incompatibility  may  perhaps  be  explained 
by  assuming  that  a  submarginal  glacial  stream  had  accumulated  sufficient 
hydrostatic  pressure  to  carry  a  strong  current  into  the  extra-marginal  lakes. 


THE  MAESEILLES  MOEAIS^E.  315 


INNER-BORDER  TILL  PLAIN. 


On  the  inner  border  of  the  Marseilles  moraine  fit'om  northern  Kendall 
County,  where  it  separates  from  the  Minooka  Ridge,  southward  through 
Grundj  and  adjoining  portions  of  Lasalle  and  Livingston  counties,  and 
thence  eastward  through  Kankakee  County,  there  is  a  till  plain  which 
shows  a  perceptible  descent  away  from  and  nearly  at  right  angles  to  the 
moraine.  As  the  moraine  describes  nearly  a  half  circle  in  this  interval,  the 
sloping  plain  converges  toward  a  focal  point,  which  is  located  near  the  head 
of  the  Illinois  River.  There  is  a  similar  descent  toward  the  head  of  the 
Illinois  from  the  east ;  thus  a  basin  is  formed,  which  is  commonly  known  as 
the  Morris  Basin,  fi-om  the  city  of  Morris,  which  stands  near  its  central 
portion.  The  slopes  of  this  plain  are  well  shown  by  the  direction, of  drain- 
age lines,  which  converge  from  all  quarters  toward  the  head  of  the  Illinois 
River.  (See  topographic  map,  PL  III.)  At  present  the  basin  is  deeply 
notched  at  its  western  border  by  the  valley  of  the  Illinois  River,  but  at  the 
withdrawal  of  the  ice  sheet  tlie  e"\ddeuce  is  quite  clear  that  the  western  rim 
stood  sufficiently  high  to  hold  a  lake  of  considerable  size  in  the  Morris 
Basin.     The  history  of  this  lake  is  discussed  in  some  detail  below. 

On  the  border  of  this  till  plain  next  to  the  moraine  the  surface  is 
gently  undulating,  but  within  a  few  miles  it  become  an  almost  expression- 
less plain.  In  Kankakee,  southwestern  Will,  and  eastern  Grundy  counties 
the  plain  is  occupied  by  sand  dunes  and  beaches ;  elsewhere  it  is  generally 
veiy  smooth.  There  are,  however,  a  few  points  in  southeastern  Kendall 
and  northeastern  Grrundy  counties  where  the  di-ift  is  slightly  ridged. 

In  the  vicinity  of  Lisbon,  in  southern  Kendall  County,  the  drift  is 
insufficient  to  conceal  the  inequalities  of  the  limestone  ridges,  but  the 
surface  is  only  gently  rolling,  the  crests  of  the  ridges  being  scarcely  more 
than  20  feet  above  the  sags.  This  area  is  2  to  2  J  miles  from  north  to  south 
and  5  to  6  miles  from  east  to  west,  and  lies  mainly  in  the  south  half  of 
T.  35,  R.  7  E. 

The  drift  along  the  border  of  the  Marseilles  moraine  has  generally  a 
thickness  of  100  feet  or  more,  but  upon  descending-  the  slope  toward  the 
head  of  the  Illinois  the  thickness  decreases,  and  there  are  extensive  areas 
in  eastern  Grundy,  southwestern  Will,  and  northern  Kankakee  counties 
where  rock  is  encountered  at  very  slight  depth,  so  that  the  shallow  ravines 


316  THE  ILLINOIS  GLACIAL  LOBE. 

and  shallow  wells  and  even  the  cellar  bottoms  reach  it.  The  drift  appears 
to  be  composed  mainly  of  till  and  differs  in  no  essential  degree  from  that 
found  in  the  Marseilles  moraine.  The  j^ellow  or  oxidized  till  at  surface  is 
apparently  somewhat  thicker  than  on  the  moraine.  At  the  surface  there 
are  extensive  deposits  of  sand  and  silt  occun-ing  up  to  an  altitude  of  nearly 
650  feet,  though  most  abundant  at  575  feet  or  less,  which  in  all  probability 
are  referable  to  the  lake  that  occupied  the  basin.  These  deposits  in  some 
places  reach  considerable  depth  and  are  either  accumulated  in  knolls  and 
ndges  or  spread  evenly  over  the  surface.  In  other  places  they  are  insuffi- 
cient to  conceal  the  surface  bowlders. 

In  the  greater  part  of  this  district  wells  may  be  obtained  at  a  depth  of 
25  feet  or  less.  In  some  cases  they  are  obtained  at  the  base  of  the  sui-face 
sand;  in  others  near  the  junction  of  the  yellow  and  blue  tills,  there  being 
not  infrequently  thin  beds  of  sand  and  gravel  at  that  horizon;  in  still  other 
cases  they  enter  the  blue  till.  Several  flowing  wells  have  been  obtained 
from  the  di'ift.  These  are  discussed  in  connection  with  other  wells,  in  the 
detailed  discussion  of  wells  given  in  Chapter  XIV. 


CHAPTER    X. 
THE  LATE  WISCONSIN  DRIFT  SHEETS. 

BASIS  FOR   SEPARATION  FROM  THE  EARLV  WISCOXSIK. 

The  necessity  for  sepai^ating  the  moraines  of  this  later  drift  into  two 
series  was  brought  out  by  Chamberhn's  early  studies  in  eastern  Illinois  and 
western  Indiana.  He  discovered  that  the  very  bowldery  morainic  belts  of 
Benton  and  Warren  counties,  Indiana,  pass  directly  across  the  line  of  the 
earlier  moraines  which  lead  up  to  them  from  the  west.  The  fact  was  also 
noted  that  the  earlier  series  of  moraines  are  not  markedly  older  than  the 
later  series.  In  view  of  this  freshness  of  the  drift  of  the  earlier  series  and 
of  certain  obscure  tracts  in  the  Kankakee  Basin,  he  makes  the  following 
statement:^ 

The  drift  of  this  area  [Kankakee  Basin]  bears  undoubted  evidence  of  being- 
recent,  and,  though  this  is  in  considerable  part  due,  superficially,  to  aqueous  agencies, 
it  seems  to  me  probable  that  the  region  will  prove  to  have  been  largely,  possiblj'  com- 
pletely, covered  by  ice  iu  the  earliest  stage  of  the  second  glacial  epoch.  It  is  not, 
however,  traversed  by  conspicuous  moraines,  at  least  not  by  any  as  well  developed 
as  those  outlined.  Low-ridged  belts  of  subdued  morainic  aspect  have  been  observed 
at  numerous  points,  but  their  relations  have  not  yet  been  traced  ont. 

A  similar  qualifying  remark  may  here  be  made  concerning  a  considerable  area 
in  northern  Illinois,  outside  the  moraine  described  in  this  paper.  The  freshness  of  its 
drift  and  the  nnsculptured  contour  of  its  surface  bear  evidence  of  recent  origin. 

Subsequent  studies  by  Chamberlin  and  liis  associates  have  brought  out 
more  clearly  the  evidence  that  the  bowldery  moraines  are  out  of  harmony 
in  trend  with  the  moraines  of  the  early  Wisconsin  series.  Thej^  have  also 
shown  that  the  bowldery  moraines  present  a  somewhat  fresher  surface  con- 
tour than  the  moraines  overridden  by  them.  It  is  upon  the  basis  of  these 
differences  in  trend  and  in  freshness  of  contour  that  the  removal  from  the 
early  Wisconsin  has  been  made.  As  yet  no  soil  or  leached  or  weathered 
zone  has  been  found  separatmg  the  drift  of  the-  two  series,  and  it  still  seems 

■  Third  Annual  Report  U.  S.  Geol.  Survey,  p.  331. 

317 


318  THE  ILLINOIS  GLACIAL  LOBE. 

questionable  whether  the  interval  between  their  deposition  was  sufficiently 
long  to  justify"  their  reference  to  distinct  glacial  stages.  The  shifting  of  the 
ice  lobes,  however,  is  thought  to  indicate  a  retreat  of  some  consequence 
between  the  two  ice  advances — a  retreat  probably  much  greater  than  took 
place  between  the  formation  of  neighboring-  moraines  of  the  early  Wis- 
consin series. 

OUTLII^B  OF  THE  I.ATE  WISCONSIIST  BORDER. 

So  far  as  is  yet  known,  the  oldest  moraine  of  the  late  Wisconsin  series 
is  the  Iroquois  moraine  of  the  coalesced  Erie-Saginaw  lobe.  Full  correla- 
tions, however,  have  not  been  made  of  moraines  of  this  series  in  the  several 
ice  lobes.  This  moraine  appears  in  northwestern  Pulaski  County,  Indiana, 
in  the  midst  of  the  sand  area  known  as  "Old  Lake  Kankakee,"  and  leads 
southwestward  along  the  divide  between  the  Iroquois  and  Kankakee  rivers, 
across  Jasper  and  Newton  counties,  Indiana,  to  eastern  Iroquois  County, 
Illinois.  It  there  swings  abruptly  southward,  crossing  the  Iroquois  River 
between  the  State  line  and  Watseka,  Illinois,  and  soon  curves  to  the 
so"utheast,  reentering  Indiana  in  northwestern  Benton  County.  It  thence 
passes  soiitheastward  across  Benton  and  Warren  counties,  coming  to  the 
Wabash  Valley  at  Williamsjiort.  Its  further  continuation  to  the  southeast  is 
indicated  approximately  on  the  map  accompanying  Professor  Chamberlin's 
paper  in  the  Third  Annual  Report.  The  moraine  is  discussed  in  detail  in  a 
report  now  in  preparation,  which  embraces  the  moraines  of  the  Erie  lobe. 

From  the  point  Avhere  the  Iroquois  moraine  turns  southward  in  eastern 
Iroquois  County,  Illinois,  a  bowldery  belt  leads  northwestward  past  Ste. 
Anne  to  the  Kankakee  River  just  above  the  city  of  Kankakee,  being  closely 
associated  with  the  Marseilles  moraine  to  that  point,  but  apparentl)^  distinct 
from  it  at  points  farther  north  and  west.  This  belt  is  discussed  below  as  a 
possible  correlative  of  the  Iroquois  moraine.  By  this  interpretation  the 
moraine  occupying  the  divide  between  the  Iroquois  and  Kankakee  rivers  in 
Newton  and  Jasper  counties,  Indiana,  is  interlobate  in  character.  This 
interpretation  would  furnish  an  explanation  for  the  abrupt  eastern  termina- 
tion of  the  moraine,  there  being  a  coalescence  of  the  lobes  so  complete  in 
the  eastern  part  of  the  Kankakee  Basin  that  no  moraine  was  formed. 
Unfortunately,  tlae  features  are  somewhat  vague  in  the  district  northwest 
from  the  ])oint  where  the  Iroquois  moraine  turns  soutli  and  the  interpretation 


THE  MINOOKA  TILL  EIDGE.  319 

is  not  entirely  be5^ond  question.  There  seem,  however,  sufficient  grounds 
for  referring  certain  featm-es  in  that  region  provisionally  to  the  late  Wiscon- 
sin deposits.  These  features  are  of  two  classes,  namely,  bowlder  belts  and 
ridged  drift.  These  are  discussed  separately,  since  their  association  is  not 
sufficiently  close  to  make  it  certain  that  they  represent  a  single  ice  advance. 
As  indicated  below,  the  ridging  (discussed  under  the  head  "Minooka  Till 
Ridge")  may  have  preceded  rather  than  accompanied  the  deposition  of  the 
bowlders. 

SECTION  I.     THE  MI3\^OOKA  TIIiL  KIDGE. 

DISTRIBUTION. 

This  till  ridge  receives  its  name  from  the  village  of  Minooka,  in  north- 
eastern Grrundy  County,  which  is  situated  on  its  crest.  As  noted  above,  it 
is  united  with  the  Marseilles  moraine  in  Kane  County,  and  being  smaller 
than  that  moraine  its  discrimination  may  be  made  with  difficulty.  In  the 
northeast  part  of  Kendall  County  it  leaves  the  Marseilles  moraine  and  takes 
a  southward  course  along  the  county  line  between  Kendall  and  Will  and 
Grrundy  and  Will  counties  to  the  head  of  the  Illinois  River.  The  crest  as  a 
rule  lies  in  the  eastern  tier  of  sections  in  Kendall  and  Grundy  counties, 
but  in  places  touches  western  Will  County.  The  width  of  the  ridge,  includ- 
ing both  slopes,  is  scarcely  2  miles.  It  consists  of  a  single  smooth  ridge 
on  whose  crest  and  slopes  there  are  few  swells  exceeding  10  feet  in  height. 
The  ridge  is  crossed  by  two  valley-like  depressions  -which  unite  near  its 
western  edge  in  sec.  13,  T.  36,  R.  8  E.,  and  drain  west  into  Au  Sable  Creek. 
These  are  cut  down  to  the  level  of  the  plain  on  the  east  side  of  the  ridge. 
They  apparently  were  formed  by  the  discharge  of  water  from  the  ice 
margin  or  ponded  between  the  ridge  and  the  receding  ice  front. 

PROBABLE   LINE   OP   CONTINUATION. 

Up  the  Kankakee  River,  from  the  head  of  the  Illinois  nearly  to  the 
State  line,  there  is  an  occasional  development  of  low  di-ift  ridges  and  gentle 
swells  on  the  north  side  of  the  valley.  On  that  side  of  the  river,  1  to  3 
miles  back  from  the  stream,  there  is  an  abrupt  bluff-like  rise  of  25  to  50 
feet,  and  the  ridges  and  swells  front  this  bluff  or  lie  immediately  back  of  it. 
This  system  of  ridges  and  swells  nearly  everywhere  stands  slightly  higher 
than  the  plain  which  lies  to  the  north.     In  the  vicinity  of  Kankakee  this 


320  THE  ILLINOIS  GLACIAL  LOBE. 

ridged  belt  borders  the  river  quite  closely  and  part  of  the  city  stands  on  it. 
From  that  city  it  takes  a  course  slightly  north  of  east  to  Exline,  cutting 
across  the  great  bend  in  the  river  opposite  the  mouth  of  the  Iroquois  River. 
Some  uncertainty  is  felt  as  to  its  continuation  from  this  point.  It  ma^- 
continue  eastward  into  Indiana  parallel  to  the  river  and  pass  beneath  the 
Valparaiso  moraine,  though  it  seems  quite  as  probable  that  it  finds  its  con- 
tinuation in  the  belt  leading  southeast  from  Mount  Langum,  above  described 
(see  Marseilles  moraine).  The  break  opposite  Mount  Langum  is  merely 
the  width  of  the  Kankakee  Valley,  scarcely  2  miles. 

No  similar  ridging  occurs  on  the  south  side  of  the  river  in  western 
Kankakee  or  in  Will  County.  There  is  instead  a  gradual  rise  from  the  low 
bank  of  the  river  southward  through  a  sand-covered  disti-ict  to  the  till  plain 
which  lies  inside  the  Marseilles  moraine.  The  greater  accumulation  of  drift 
on  the  north  side  of  the  river,  taken  in  connection  with  the  occasional 
development  of  moraine-like  features,  apparently  supports  the  interpretation 
thus  made — that  the  continuation  of  the  Minooka  till  ridge  may  be  found 
along  this  line. 

BELIEF. 

The  southern  end  of  the  well-defined  Minooka  Ridge  (at  the  head  of 
the  Illinois  River)  stands  100  to  110  feet  above  the  Illinois  River.  The 
general  relief  of  this  ridge  above  the  plain  which  borders  it  on  the  west  is 
50  to  70  feet.  The  profile  of  the  Chicago,  Rock  Island  and  Pacific  Rail- 
road, which  crosses  the  ridge  at  Minooka,  shows  a  relief  on  the  west  side 
of  about  65  feet.  The  relief  is  slightly  less  on  the  east  and  is  also  less 
abrupt  than  on  the  west. 

The  bluff-like  ridge  along  the  Kankakee,  where  best  developed,  stands 
but  30  to  40  feet  above  the  plains  on  the  north,  and  its  usual  relief  on  that 
side  is  only  10  to  20  feet.  On  the  side  next  the  Kankakee  there  is  a  gen- 
eral relief  of  30  feet  or  more,  with  occasional  points  where  it  exceeds  50 
feet.  Evidently  a  portion  of  this  relief  is  due  to  stream  erosion,  but  the 
excavation  is  so  shallow  that  the  stream  is  responsible  for  scarcely  20  feet 
of  the  relief 

THICKNESS   OF  DRIFT. 

Beneath  the  crest  of  the  Minooka  Ridge,  from  the  head  of  the  Illinois 
northward,  the  drift  is  shown  by  wells  to  be  130  to  150  feet  and  in  one 


THE  MINOOKA  TILL  EIDGE,  321 

instance  nearly  200  feet  in  thickness,  the  thickness  as  compared  with  that 
on  bordering  j^lains  being  about  as  much  greater  as  the  measure  of  the 
relief  of  the  ridge.  In  the  portion  along  the  Kankakee  the  thickness 
seldom  exceeds  60  feet,  but  is  g-reater  along  the  higher  parts  than  on  the 
lower  or  than  on  the  border  plain,  as  would  be  expected  from  the  relief 
which  it  presents. 

STRUCTURE    OF    DRIFT. 

In  the  ridge  north  from  the  head  of  the  Illinois  the  surface  portion  of 
the  drift  to  a  depth  of  8  to  12  feet  consists  of  a  yellow  till  containing  many 
pebbles.  It  is  sandy  in  places,  but  as  a  rule  is  a  stiff,  sticky  clay,  very 
slowly  pervious  to  water. 

This  yellow  till  is  imderlain  by  a  grayish  blue  till  containing  occasional 
gravel  or  sand  veins,  which  furnish  water  in  small  quantities.  This  bed  of 
till  often  has  a  thickness  of  100  feet  or  more.  Beneath  it  there  is  in  places 
a  heavy  deposit  of  sand.  This  may  not  underlie  the  whole  of  the  ridge, 
but  has  been  penetrated  in  several  wells  along  the  crest  in  Kendall  County. 
It  furnishes  abundance  of  water  for  wells. 

The  ridge  from  Minooka  northward  carries  a  black  surface  soil  several 
inches  in  depth,  such  as  is  found  on  the  bordering  plains.  There  are  few 
surface  boAvlders,  and  pebbles  are  rare  within  18  inches  of  the  surface. 

The  drift  along  the  north  border  of  the  Kankakee  is  mainly  till,  and 
sui-face  bowlders  are  more  abundant  than  in  the  portion  north  of  the  head 
of  the  Illinois  River. 

CHARACTER    OF    THE    OUTWASH. 

The  well-defined  portion  of  the  Minooka  Ridge  has  a  low  part  of  the 
Morris  Basin  on  its  outer  border.  Unless  the  outlet  down  the  Illinois  had 
been  opened  to  a  level  as  low  as  this  part  of  the  basin,  the  basin  would  have 
held  a  lake,  and  there  scarcely  could  have  been  vigorous  discharge  ft'om  the 
Minooka  Ridge.  Terraces  on  the  Des  Plaines  River  which  have  their  head 
in  the  Valparaiso  moraine  and  were  formed  in  connection  with  that  moraine 
indicate  that  a  lake  stood  in  this  basin  at  the  head  of  the  Illinois  while  they 
were  forming  and  that  its  level  was  about  560  feet  above  tide,  or  60  feet 
above  the  present  head  of  the  Illinois  River.  This  lake  level  is  well  defined 
also  by  beaches  which  are  to  be  seen  both  north  and  south  of  the  Illinois. 
MON  xxxviii 21 


322  THE  ILLINOIS  GLACIAL  LOBE. 

Such  being-  the  case  at  the  time  tlie  Valparaiso  moraine  was  forming-,  it  fol- 
lows that  at  the  time  the  Minooka  Ridge  was  formed  the  lake  stood  fully  as 
high,  if  not  higher,  for  the  Minooka  Ridge  antedated  the  the  Valparaiso 
moraine  in  its  formation.  The  low  part  of  the  basin  immediately  west  of 
the  Minooka  Ridge  stands  only  a  few  feet  above  the  level  of  the  beaches 
referred  to  and  would  apparently  have  been  extensively  inundated  during- 
the  melting-  of  the  ice  sheet,  even  if  the  outlet  from  the  Morris  Basin  liad 
been  cut  down  to  the  level  of  the  well-defined  beach  bordering  the  Illinois 
River.  A  vigorous  discharge  of  waters  across  the  basin  could  scarcely  be 
expected.  Certain  features  which  suggest  vigorous  discharge  Avill  next  be 
considered. 

The  channels  noted  above,  which  cross  the  ridge  a  few  miles  north  of 
the  head  of  the  Illinois,  seem  to  have  been  made  by  a  stream  with  a  current 
having-  considerable  ^'olume,  if  not  considerable  strength.  They  are  cut 
down  to  a  gradient  too  low  to  give  the  present  small  stream  which  drains 
them  a  good  gradient,  and  are  consequently  occupied  by  marshes.  The 
conditions  under  which  they  were  formed  were  probabh'  similar  to  those 
wliich  caused  the  gaps  in  the  Marseilles  moraine  discussed  above  (pp  310, 
314).  A  thin  coating  of  sand  is  found  in  the  portion  of  the  basin  immedi- 
ately west  and  south  of  these  channels,  a  featui'e  which  implies  current 
actioii,  but  perhaps  no  stronger  than  is  consistent  with  the  presence  of  a 
lake  or  ver)-  broad  lake-like  stream.  On  the  whole,  the  evidence  seems 
insufficient  to  establish  the  existence  of  good  drainage  conditions. 

Turning  to  the  Kankakee  for  light  as  to  drainage  conditions  accom- 
pan5ang  the  formation  of  the  ridge  on  its  north  border,  it  is  found  that  sand 
deposits  occur  along  the  opposite  side  of  the  valley,  forming-  a  much  more 
conspicuous  feature  than  on  the  west  border  of  the  Minooka  Ridge.  The 
deposits  extend  back  usually  3  or  4  miles  from  the  jiresent  stream  and 
reach  an  elevation  fully  as  higli  as  the  ridge  on  the  north  side  of  the  valley. 
They  have  been  drifted  in  places  into  prominent  dunes.  This  sand  may  be 
interpreted  either  as  the  direct  outwash  from  the  ice  at  the  time  the  ridged 
belt  north  t)f  the  \^alley  was  in  process  of  formation,  or  it  may  seem  refer- 
able to  subsequent  stream  transportation,  for  the  Kankakee  Valley  ^^■as  the 
line  of  discharge  for  glacial  sf reams  issuing-  from  the  Saginaw  lobe  during 
the  ])erio(l  (■inl)riic(M|  in  tlic  I'onnation  of  two  or  more  strong  moraines,  and 
IVimi  :i   piii-t  of  llic   Laki'   Miclii'^-nii    lol)!'   ilin-iun'  tlie  formation  of  the  Val- 


THE  MINOOKA  TILL  EIDGE.  323 

paraiso  moraine.  These  glacial  streams  had  a  current  sufficiently  strong  to 
excavate  a  channel  throughout  nearly  the  entire  length  of  the  Kankakee 
Basin,  whose  north  bluff  may  still  be  seen  rising  15  to  30  feet  above  the 
Kankakee  marsh.  A  current  of  this  strength  would  seem  to  be  entirely 
adequate  to  cause  the  transportation  of  such  sand,  deposits  as  are  found  on 
the  lower  course  of  the  Kankakee.  It  may  be  questioned,  therefore, 
whether  these  deposits  may  be  referred  with  certainty  to  streams  issuing 
from  the  ice  sheet  at  the  time  the  I\Iinooka  Ridge  was  in  process  of  forma- 
tion. The  evidence  here,  as  in  the  case  of  the  channels  north  of  the  Illinois 
Valley,  is  scarcely  sufficient  to  establish  the  occurrence  of  good  drainage 
conditions  at  that  time.  The  peculiar  association  of  this  sand  belt  with  a 
bowlder  belt  is  discussed  below  (p.  326). 

Inasmuch  as  the  Iroquois  moraine  appears  to  have  been  formed  either 
contemporaneously  with  or  subsequent  to  the  Minooka  Ridge,  the  character 
of  its  outwash  may  be  found  serviceable  in  drawing  conclusions  concerning 
the  outwash  from  the  Minooka  Ridge. 

On  the  outer  border  of  the  Iroquois  moraine  in  Iroquois  County,  Illi- 
nois, and  also  in  Benton  County,  Indiana,  the  outwash  is  a  fine  sand  which 
has  been  transported  to  the  lower  parts  of  the  Iroquois  Basm  and  down  the 
valley  of  Sugar  Creek,  a  southern  tributary  of  the  Iroquois.  As  this  out- 
wash  is  in  a  district  lying  outside  the  line  of  discharge  for  the  glacial 
streams  which  traverse  the  Kankakee  Valley,  it  is  less  difficult  to  interpret 
than  the  sands  of  the  lower  Kankakee.  Its  position  is  such  as  to  be  favor- 
able for  discharge  of  water  if  no  lake  were  present,  since  there  is  a  descent 
away  from  the  outer  border  of  the  moraine.  Yet  the  fineness  of  the  mate- 
rial seems  to  indicate  that  very  imperfect  drainage  conditions  attended  the 
deposition  of  this  moraine.  The  feebleness  of  discharge  is  thought  to 
indicate  that  lake-like  conditions  may  still  have  persisted  not  only  in  the 
Morris  Basin  but  also  in  the  Kankakee  and  Iroquois  basins. 

On  the  outer  border  of  the  combined  Marseilles  and  Minooka  moraines, 
in  northern  Kendall  and  southern  Kane  cou,nties,  there  is  an  extensive 
gravelly  plain,  to  which  attention  was  called  in  connection  with  the  Mar- 
seilles moraine.  This  plain  has  not  as  yet  been  definiteh'  connected  with 
anj'-  of  the  moraines  of  the  late  Wisconsin  series.  Three  means  of  deposi- 
tion need  to  be  -  considered,  as  follows:  (1)  By  streams  flowing  down  the. 
Fox  River  Valley  during  the  formation  of   the  Valparaiso   moraine  and 


324  THE  ILLINOIS  GLAGIAL  LOBE. 

spreading  out  a  delta  similar  to  that  i'onned  in  the  lower  part  (if  the  Des 
Plaines  Valley  by  streams  issuing  from  the  same  moraine;  (2)  by  streams 
issuing  from  the  ice  at  the  time  the  Minooka  Ridge  was  forming,  for  the  ice 
at  that  time  seems  to  have  extended  as  far,  at  least,  as  the  western  edge  of 
the  Marseilles  moraine  in  Kane  County;  (3)  b}^  outwash  from  the  Marseilles 
moraine,  which  sweeps  around  the  eastern  and  southern  border  of  the  plain. 
In  the  present  state  of  knowledge  it  seems  difficult  to  draw  inferences  con- 
cerning the  date  at  which  this  plain  was  formed,' and  also  concerning  the 
broader  question  of  the  character  of  the  outwash  from  the  ice  sheet  during 
the  Minooka  substage  of  glaciation. 

Whether  the  Minooka  Ridge  is  to  be  included  in  the  late  Wisconsin 
series  can  not  perhaps  be  decided  at  the  present  stage  of  investigation.  If 
it  can  be  clearly  established  that  during  the  interval  between  the  formation 
of  the  Marseilles  moraine  and  the  Minooka  Ridge  the  outlet  down  the 
Illinois  had  been  lowered  from  about  640  feet  above  tide  (the  level  of 
ueig'hboring  outlets  through  the  Marseilles  moraine)  to  a  level  nearly  as  low 
as  the  560-foot  beach  bordering  the  Illinois  in  the  Morris  Basin,  a  corre- 
spondingly late  date  for  that  ridge  may  be  assumed.  But  at  present  there 
is  much  uncertainty  as  to  the  amount  of  work  accomplished  by  that  outlet 
prior  to  the  formation  of  the  Minooka  till  ridge.  The  bearing  of  bowlder 
belts  on  this  question  is  considered  below  (p.  327.) 

INNER-BORDER   TILL  PLAIN. 

On  the  inner  border  of  the  Minooka  Ridge,  from  the  ^'icinity  of  Elgin 
southward  to  the  head  of  the  Illinois,  there  is  a  narrow  till  plain  nowhere 
more  than  6  miles,  and  usually  but  2  or  3  miles,  in  width,  which  separates 
this  till  ridge  from  the  Valparaiso  morainic  system.  North  from  Elgin  the 
Minooka  Ridge  has  not  been  separated  from  the  Valparaiso  system.  From 
the  head  of  the  Illinois  eastward  along  the  north  side  of  the  Kankakee  Val- 
ley there  is  a  similar  till  plain  separating  the  ridged  drift  on  the  border  of 
the  valley  from  the  Valparaiso  morainic  system.  Its  width  is  gretitest  on 
the  meridian  of  Kankakee,  where  it  is  fully  12  miles,  the  usual  width  being 
only  7  or  8  miles.  East  from  Kankakee  the  till  plain  north  of  the  river 
decreases  in  width  and  extends  only  a  short  distance  east  of  the  State  line. 
The  Valparaiso  system  there  comes  to  the  boi'der  of  the  Kankakee  marsh. 


BOWLDER  BELTS.  325 

An  extensive  sand-covered  tract  south  of  tlie  Kankakee,  in  western  Indiana 
and  the  east  border  of  Illinois,  is  discussed  below. 

The  portion  of  the  till  plain  north  of  the  head  of  the  Illinois  shows 
usually  a  perceptible  descent  away  from  the  Minooka  Ridge,  accompanied 
by  a  corresponding  decrease  in  the  thickness  of  the  drift.  On  the  borders 
of  the  ridge  the  drift  is  100  feet  or  more  in  average  depth,  while  at  the  east 
border  of  the  till  plain  next  to  the  Valparaiso  system  it  is  in  places  but  20 
to  30  feet  in  depth.  The  drift  appears  to  be  mainly  soft  till,  referable  to 
the  Wisconsin  sheets.     In  places  it  is  gravelly  or  sandy  at  base. 

The  portion  of  the  till  plain  north  of  the  Kankakee  in  general  rises 
slightly  toward  the  north.  The  di'ift  is  apparently  only  30  to  40  feet  in 
average  depth.  In  places  rock  ridges  which  carry  scarcely  any  drift  rise 
slightly  above  the  general  level  of  the  plain.  Siich  ridges  may  be  seen  near 
Manteno.  The  drift  is  apparently  nearly  all  Wisconsin.  A  few  instances 
of  the  penetration  of  a  buried  soil  in  wells  were  reported  from  the  north- 
east part  of  Kankakee  County.  This  soil  is  within  a  few  feet  of  the  bottom 
of  the  a'lacial  drift.  The  drift  north  of  the  Kankakee  contains  much  sand 
and  gravel,  but  there  is  usually  a  capping'  of  till  a  few  feet  in  depth.  The 
well  sections  of  Will  and  Kankakee  counties,  presented  in  the  latter  part  of 
this  report,  will  set  forth  the  variations  in  the  structure  and  the  thickness  of 
the  drift. 

SECTION  II.    BOWLDER  BELTS. 

The  Marseilles  moraine  and  also  the  Minooka  Ridge,  as  already  indi- 
cated, carry  a  very  few^  bowlders  on  the  surface.  Bowlders  are  also  com- 
paratively rare  on  the  inner  or  eastern  slope  of  these  ridges  and  on  the  till 
plain  between  the  Kankakee  River  and  the  Valparaiso  moraine.  There  is, 
however,  a  strip  on  the  borders  of  the  sand  area  along  the  south  side  of  the 
Kankakee  in  Kankakee  and  Will  counties,  and  in  places  within  the  sand 
area,  where  bowlders  abound.  This  belt  may  connect  on  the  southeast 
with  the  Iroquois  moraine,  though  the  connection  is  rather  obscure  because 
of  sand  accumulations.  It  appears  to  find  a  continuation  northwestward  in 
Grundy  County  along  the  borders  of  Mazon  Creek,  from  the  vicinity 
of  Gardner  to  the  mouth  of  the  stream  near  Morris.  From  Morris  a  belt 
of  bowlders  extends  northward  3  or  4  miles,  beyond  which,  for  about  6 
miles,  they  are  comparatively  rare.     Near  Plattville  a  narrow  belt  sets  in, 


326  THE  ILLINOIS  GLACIAL  LOBE. 

■^lieli  leads  northward  to  the  Marseilles  moraine  and  passes  over  that 
moraine,  as  already  noted,  in  the  vicinity  of  the  valley-like  gap  east  of 
Yorkville.  The  bowlders  occupy  the  gap  and  also  the  portion  of  the  moraine 
to  the  east.  To  the  north  from  this  point  the  broad  gravel  plain  along  Fox 
River  interrupts  the  belt  for  a  space  of  3  or  4  miles,  but  at  the  north 
border  of  this  gravel  plain  bowlders  again  become  numerous  and  abound 
along  the  west  side  of  Fox  River  throughout  the  interval  between  this 
gravel  plain  and  the  composite  belt  of  moraines  above  described. 

The  boAvlders  are  unevenly  distributed,  there  being  small  tracts  and 
narrow  strips  where  they  are  so  numerous  as  to  constitute  a  serious 
obstruction  to  the  cultivation  of  the  soil,  occasionally  numbering  several 
hundi-ed  per  acre,  but  throughout  most  of  the  belts  there  are  only  a  few 
per  acre.  The  belt  taken  as  a  whole  probabh'  carries  ten  times  the  number 
of  bowlders  found  in  neighboring  districts. 

The  sand  along  the  south  border  of  the  Kankakee  is  usually  so  heavy 
that  the  .bowlders,  if  present,  would  be  obscured.  In  places  where  the  sand 
is  thin,  bowlders  are  usually  abundant.  These  oasis-like  tracts  in  the  midst 
of  the  sand  area  are  in  some  cases  difficult  to  account  for.  The  heaping  of 
the  sand  into  ridg'es  is  probably  due,  in  part  at  least,  to  wind  action,  and 
the  wind  may  also  have  been  influential  in  sweeping-  the  sand  away  from 
parts  of  the  surface.  It  seems  well,  however,  to  introduce  an  alternative  or 
supplementary  explanation,  though  the  applicability  has  not  been  fully 
tested.  By  the  alternative  interpretation  a  causal  relationship  is  suggested 
between  the  occurrence  of  Ijowlders  and  the  absence  of  sand,  and  the 
explanation  found  in  the  persistence  of  ice  where  the  bowlders  occur  until 
the  sand  had  accumulated  in  practicall}-  its  present  depth  and  topography. 
Thi^  alternative  explanation  would  also  make  the  ridging  of  the  sand  partly 
the  result  of  glacial  molding  which  has  been  intensified  by  subsequent 
seolian  action.  This  interpretation  has  been  suggested  by  featm-es  found  in 
the  old  Lake  Kankakee  district,  discussed  below. 

It  should  perhaps  be  stated  that  the  bowlders  here  or  elsewhere  in  the 
belt  can  scarcely  be  considered  a  residue  from  erosion  of  the  till,  for  they 
often  occur  on  ])lains  where  tliere  has  been  scarcely  any  opportunity  for 
erosion.  Furtliermore,  they  differ  in  constitution  from  the  coarse  rocks  of 
the  till,  being  almost  wholly  of  crvstalline  rocks  of  distant  derivation,  while 
th(.'  till  abounds  in  local  rock  fragments,  Ixith  coai'se  and  fine. 


BOWLDEE  BELTS.  327 

It  seeiTQS  more  probable  that  the  belt  marks  the  position  of  the  ice 
margin  at  some  stage  of  advance  between  the  formation  of  the  Marseilles 
and  Valparaiso  moraines.  Were  the  belt  accompanied  thronghont  bv  a 
moraine,  or  even  a  thin  sheet  of  drift,  this  interpretation  would  seem  well 
supported.  For  a  few  miles  in  the  vicinity  of  the  point  where  it  crosses 
the  Marseilles  moraine  there  are  low  knolls  accompanying  the  bowlders 
which  may  prove  to  be  of  the  same  date  as  the  bowlder  deposition.  They  are 
much  smaller  than  the  swells  on  the  Marseilles  moraine,  being  usualh^  only 
3  to  6  feet  in  height  and  covering  a  few  square  rods  each.  They  inclose 
shallow  saucer-like  depressions,  and  on  the  whole  give  the  surface  a  fresher 
contour  than  is  presented  by  the  portion  of  the  Marseilles  moraine  to  the 
west.  The  portion  of  the  belt  from  Morris  northward  was  made  a  subject 
of  joint  investigation  by  Professor  Chamberlin  and  the  writer,  and  to 
each  of  us  the  surface  contours  appeared  somewhat  fresher  along  the  line 
of  the  bowlder  belt  than  in  the  district  to  the  west.  But  the  development 
of  a  new  or  distinct  topography  in  connection  with  the  bowlder  belt  seems 
at  best  to  be  limited  to  the  immediate  vicinity  of  the  Marseilles  moraine, 
and  leads  us  to  feel  some  doubt  concerning  the  interpretation  of  the  occur- 
rence of  a  thin  sheet  of  di'ift  in  connection  with  the  bowlder  belt- 
It  will  be  observed  that  the  course  of  this  bowldery  strip  is  nearly 
parallel  with  the  Minooka  Ridge  and  its  supposed  eastern  continuation  along 
the  Kankakee.  This  parallelism  has  suggested  the  interpretation  that  the 
bowlder  belt  may  be  closely  related  to  that  ridge  Possibly  there  was  a 
temporary  advance  of  the  ice  beyond  the  position  it  held  while  forming 
the  ridge,  or  possibly  the  accumulation  of  the  bowlders  and  the  ridffe 
occurred  at  the  same  time,  the  former  being  at  the  extreme  margin  and  the 
latter  a  short  distance  back  from  the  margin.  The  smoothness  of  the  ridp'e 
apparently  favors  the  interpretation  that  it  is  a  submarginal  accumulation. 
Another  interpretation  refers  the  formation  of  the  bowldery  strip  to  an 
advance  subsequent  to  the  formation  of  the  Minooka  Ridge.  In  that  case 
the  smoothness  of  the  ridge  may  be  due  to  its  having  been  overridden. 

It  seems  highly  probable  that  this  bowldery  strip  is  to  be  correlated 
with  the  Iroquois  moraine  and  associated  bowlder  belts  found  in  Iroquois 
County,  Illinois,  and  Benton  and  Warren  counties,  Indiana,  which  are 
referred  to  the  late  Wisconsin  invasion;  The  indefiniteness  of  the  bowldery 
strip  in  the  sandy  districts  of  eastern  Kankakee  and  northeastern  Iroquois 


328  THE  ILLI]S"OIS  GLACIAL  LOBE. 

counties  prevents  a  full  and  satisfactory-  correlation.  But  notliing  to  oppose 
the  con-elation  has  yet  been  discovered.  At  present  it  seems  necessary  to 
leave  luisettled  both  its  relation  to  the  Iroquois  moraine  and  to  Minooka 
Ridge. 

SECTIOX  III.     X,AKE  KAXKAKEE. 

Nearlv  tlairty  years  ago  Mr.  F.  H.  Bradley  applied  the  name  Lake  Kan- 
kakee to  a  body  of  water  which  he  thought  formerly  occupied  a  large  part 
of  the  Kankakee  di-ainage  basin.^  The  existence  of  a  lake  in  this  region  was 
suggested  bv  the  occun'ence  of  deposits  of  sand  outside  the  limits  of  the 
present  Kankakee  marsh.  Mr.  Bradley  recognized  the  influence  of  wind  in 
distiibuting  sand  over  areas  not  covered  by  the  lake,  but  considered  the 
evidence  satisfactory  that  along  the  line  of  the  Louisville,  New  Albany  and 
Chicago  Railroad  lake  water  had  reached  an  elevation  about  685  feet  above 
tide.  He  had  not  full  opportunity  to  explore  the  region;  hence  liis  outline 
of  the  extent  of  the  lake  is  rather  indefinite. 

Chamberlin  touched  briefly  upon  this  sand  area  in  his  paper  in  the 

Third  Annual  Report,  as  follows  :' 

These  dunes  are  a  portion  of  a  somewhat  extensive  tract,  or  i^erhaps  rather  a 
series  of  tracts,  in  northwestern  Indiana,  the  precise  distribution  and  origin  of  which 
are  yet  undetermined.  They  lie  mainly  in  the  Kankakee  Basin,  which  was  formerly 
occupied  by  an  extensive  lake  or  lacustral  river — "Old  Lake  Kankakee''  of  Bradley — 
and  have  been  thought  to  be  its  shore  accumulations;  but  their  very  wide  extent  and 
great  mass  relative  to  the  lake  area,  as  well  as  certain  features  of  their  known  distri- 
bution, throw  doubt  upon  the  adequacy  of  this  explanation.  It  would  seem,  froui  a 
consideration  of  the  glacial  distribution  of  the  second  epoch,  that  this  region  must 
have  been  the  avenue  of  discharge  of  vast  quantities  of  water,  shed  from  the  adjacent 
slopes  of  the  great  glaciers  occupying  the  basins  of  Lakes  Michigan,  Huron,  and 
western  Erie.  The  gi-eat  accumulations  of  sand  probably  had  their  ulterior  origin  in 
this  exceptional  drainage,  and  were  subsequently  modified  by  lacustrine,  Huvial,  and 
a-olian  action.  Their  history  is  one  of  much  interest,  and  its  satisfactory  determina- 
tion can  scarcely  fail  to  reward  industrious  investigation  when  pursued  in  the  light  of 
the  glacial  phenomena  now  under  consideration,  and  may,  in  turn,  cast  refiex  light 
upon  them.  But  however  that  may  be,  for  the  present,  these  dunes  interpose  an 
element  of  uncertainty  in  the  tracing  of  the  moraine  at  what  would,  in  any  event,  be 
a  critical  portion  of  its  course,  for  it  is  impossible  to  determine  the  character  of  the 
drift  which  they  conceal. 

The  extent  of  the  sand  in  the  Kankakee  Basin  and  in  distrii-ts  to  tlie 
south  has  been  further  iiivestigated  by  Chamberlin  since  the  above  was 

'  Geo]ogy  of  Illinois,  Vol.  IV,  1«70,  pp.  226-229. 

-Third  Annual  Report,  U.  S.  Geol.  Snrvey,  1881-82, 1883,  pp.  330-33L 


LAKE  KANKAKEE.  329 

written,  as  well  as  by  Prof.  A.  H.  Purdue  and  the  writer.  The  limits  have 
been  determined  with  considerable  accuracy,  and  the  general  features  of 
the  area  have  also  been  studied.  The  phenomena,  as  will  be  seen,  are  of  a 
peculiarly  puzzling  natiu'e,  and  as  yet  a  fully  satisfactory  interpretation  of 
them  has  not  been  reached. 

EXTENT   OF   THE   SAND. 

Beginning  at  the  northeast  and  passing  southward,  the  sand  is  found  to 
have  its  eastern  limit  at  the  border  of  the  Maxinkuckee  moraine  of  the 
Saginaw  ice  lobe  in  western  Marshall  County,  Indiana  (see  PI.  VI).  A  few 
dunes  occur  on  the  moraine,  but  the  continuous  sand  follows  approximately 
the  west  border.  Farther  north,  in  St.  Joseph  County,  a  gravel  plain  occu- 
pies the  outer  or  west  border  of  the  Maxinkuckee  moraine.  The  moraine 
swings  eastward  along  the  north  side  of  Tippecanoe  River  in  northern 
Fulton  County,  and  a  narrow  sandy  belt  extends  up  the  Tippecanoe 
Valley  along  the  outer  border  of  this  moraine  as  far  as  Rochester,  but  the 
east  border  of  the  main  sand  area  continues  southward  through  Avestern 
Fulton  County  and  northwestern  Cass  County  to  the  vicinity  of  Lake 
Cicott.  Purdue  reports  that  for  aboiit  9  miles  north  of  Lake  Cicott  a  well- 
defined  sand  ridge  forms  the  east  border  of  the  till  plain  that  descends 
westward  to  the  Tippecanoe  River.  This  ridge  turns  abruptly  westward 
near  Lake  Cicott  and  is  nearly  continuous  to  the  Tippecanoe  Valley  at 
Monticello.  For  a  part  of  this  course  the  ridge  lies  along  the  north  slope  of 
a  moraine  of  the  Erie  lobe.  After  crossing  Tipjoecanoe  River  at  Monticello 
the  moraine  turns  south,  while  the  ridg-e  continues  in  a  course  slightly 
south  of  west  about  to  the  line  of  White  and  Benton  counties.  From  this 
point  a  narrow  sand  ridge  has  been  traced  by  Purdue  in  a  course  north  of 
west  nearly  to  Kentlaud,  Indiana.  There  is,  however,  very  little  sand  on 
the  surface  for  several  miles  north  from  this  ridge,  and  he  did  not  succeed 
in  tracing  the  ridge  farther  west. 

Purdue  reports  that  there  is  a  somewhat  broken  east-to-west  sand  ridge 
north  of  Indian  Creek  in  southeastern  Pulaski  County,  which  passes  through 
the  village  of  Rosedale  (Oak  post-office),  where  it  presents  large  dunes,  and 
thence  turning  northeastward,  terminates  at  a  gravelly  knoll  in  the  north- 
east corner  of  T.  29,  R.  1  W.  The  area  from  this  ridge  north  to  and  beyond 
the  middle  of  Tippecanoe  Township  is  an  extensive  sandy  plain,  with  the 


330  THE  ILLINOIS  GLACIAL  LOBE. 

exception  of  some  short  ridges  of  sand.  There  are  also  tlie  following  areas 
within  tliis  plain  where  sand  is  not  present:  (1)  A  small  area  in  eastern 
Pulaski  Connty,  li  miles  north  of  Bruce's  Lake;  (2)  an  area  south  of 
Brace's  Lake  extending  south  to  Little  Mill  Creek  and  west  about  3  miles 
from  the  county  line;  (3)  between  Mill  Creek  and  Little  j\Iiir  Creek;  (4)  a 
small  area  about  Star  City.  This  ridge  has  an  altitude  nearly  as  great  as 
that  of  the  ridge  south  of  it,  but  its  relation  to  that  ridge  and  to  the  border 
of  the  sand  area  was  not  clearly  worked  out. 

Another  nan-ow  sand  ridge  was  traced  by  Purdue  from  Monon  Creek, 
about  5  miles  southwest  of  the  village  of  Monon,  nearly  directly  west  for 
about  20  miles  to  Percy  Junction  in  Newton  County.  This  ridge  con- 
stitutes the  south  border  of  the  naain  sand  area  in  Jasper  County.  West 
and  ncirthwest  from  the  western  end  of  this  ridge  there  are  a  few  low  sand 
ridges,  but  these  occupy  only  a  small  part  of  the  surface  and  do  not  have 
definite  connection  with  each  other  nor  with  the  long-  ridge  just  mentioned. 
There  is  enough  surface  sand,  however,  to  indicate  that  that  region  was 
covered  by  a  body  of  water.  The  Iroquois  moraine,  on  the  north  side  of 
the  Iroquois  River,  appears  to  have  been  partially  submei-ged,  but  its 
highest  parts  probably  rose  above  the  water  and  shut  in  a  bay  on  the 
south,  in  which  wave  action  was  not  .sufficiently  strong  to  foi'm  heavy  sand 
deposits. 

The  south  border  of  the  main  sand  area  follows  the  north  slope  of  the 
moraine  westward  into  Iroquois  County,  Illinois,  and  there  swings  south- 
ward with  the  Iroquois  moraine  to  Coon  Creek,  in  southwestern  Sheldon 
Township,  foi'ming  apjjarently  an  outwash  apron,  as  noted  abo^■e. 

A  belt  of  dunes  leads  westward  from  this  sand  area  across  Belmont 
and  Crescent  townships.  There  is  considerable  siu'face  sand  from  this  belt 
of  dunes  northward,  but  to  the  west  and  northwest  only  occasional  low 
sandy  ridges  and  tliin  patches  of  sand  are  found.  A  sand  ridge,  as  noted 
on  a  previous  page,  passes  westward  from  the  southwest  part  of  the  main 
sand  area  in  central  Iroquois  County  through  Onarga  and  Ridgeville  to  the 
east  fork  of  Vermilion  River,  through  which  there  was  probably  a  tem- 
porar^'  westward  outlet  to  the  Vermilion  Basin,  and  thence  to  the  Illinois. 
Possibly  this  san<l  ridiic  and  the  belt  of  dunes  with  which  it  connects  at 
the  east  are  independent  of  tlic  sand  Ijordering  the  Iroquois  moraine. 


LAKE  KANKAKEE.  331 

The  west  border  of  the  Iroquois  sand  area  follows  nearly  the  north 
flowing  part  of  Iroquois  River  northward  to  northern  Iroquois  County,  and 
there  swings  eastward  along  Beaver  Creek  Valley,  crossing  the  Marseilles 
moraine  between  St.  Anne  and  St.  Mary,  and  thence  extending-  both  east- 
ward and  westward  into  the  Kankakee  Basin. 

As  noted  above,  the  sand  is  continuous  along  the  soutli  border  of  the 
Kankakee  to  Grundy  County,  and  thence  westward  along  the  Illinois  to 
the  borders  of  the  Marseilles  moraine.  The  north  border  of  the  sand 
follows  the  low  bluff  on  the  north  side  of  the  Kankakee  from  Will  County, 
Illinois,  eastward  to  the  head  of  the  Kankakee,  where  the  tracing  began. 

It  wall  be. observed  that  this  sand-covered  district  occupies  not  only  a 
large  part  of  the  watershed  of  the  Kankakee  but  also  a  part  of  the  Tippe- 
canoe watershed.  It  embraces  an  area  of  approximately  3,000  square 
miles,  in  which  sand  deposits  are  nearly  continuous.  To  this  about  300 
square  miles  should  be  added  to  extend  the  area  to  the  extreme  limits  of 
the  sand  ridges. 

RANGE  IN  ALTITUDE  OF  THE  BORDER  OF  THE  SAND. 

At  the  eastern  border  plane-surfaced  deposits  of  sand  and  also  of 
gravel  occur  up  to  an  altitude  of  about  750  feet,  and  dunes  are  found  on 
the  moraine  at  an  altitude  of  fully  800  feet  above  tide.  Along  the  south 
border  the  altitude  of  the  sand  ridge  ranges  from  700  feet  or  less  at  the 
Tippecanoe  River  to  about  750  feet  in  Cass  County  and  in  western  White 
and  northern  Benton  counties.  The  altitude  decreases  upon  passing  west- 
ward from  Benton  County,  the  highest  sand  deposits  in  western  Iroquois 
County,  Illinois,  being  about  675  feet,  and  the  outlet  from  the  Iroquois  to 
the  Vermilion  across  Ford  County  scarcely  650  feet.  The  highest  well- 
defined  beach  along  the  Illinois  in  the  Morris  Basin  is  but  560  feet.  On  the 
north  border  of  the  Kankakee  marsh  the  altitude  decreases  from  750  feet 
or  more  in  western  St.  Joseph  County,  Indiana,  to  about  650  feet  at  the 
State  line  and  570  feet  at  the  mouth  of  the  river.  In  general  there  is  a 
westward  descent  in  the  sand-covered  area,  the  onh'  prominent  exce|)tion 
being  a  depression  in  the  southeast  part  on  the  borders  of  the  Tippecanoe 
River.  The  outer  sand  ridge  there  stands  fully  50  feet  lower  than  20  miles 
west  at  the  line  of  White  and  Benton  counties.  The  outer  ridffe  is  main- 
tained  continuously  up  this  grade  of  50  feet,  from  Reynolds  to  tlie  Benton 


332  THE  ILLIj!^OIS  GLACIAL  LOBE. 

County  line,  and  thence  westward  down  a  similar  grade  to  where  it  dies  out 
near  Kentland  (Purdue).  The  long  ridge  a  few  miles  to  the  north  appar- 
ently holds  a  nearly  uniform  elevation  about  680  or  685  feet  above  tide. 
As  indicated  in  the  topographic  map,  PI.  Ill,  much  of  the  area  east  of  the 
State  line  stands  above  700  feet.  It  should  also  be  noted  that  in  the  midst 
of  the  sandy  area  the  altitude  is  about  as  great  as  on  the  borders. 

SURFACE    CONTOURS. 

The  greater  part  of  the  sand-covered  area  has  a  nearly  plane  surface. 
The  Kankakee  marsh,  with  an  area  of  nearly  1,000  square  miles,  is  very 
flat,  while  the  portion  north  of  the  marsh  has  scarcely  an}'  ridges  worthy 
of  note.  In  southeastern  Pulaski  and  northern  White  counties,  Indiana, 
the  surface  is  mainly  level  and  level  tracts  are  quite  extensive  in  southern 
Jasj^er  County.  In  Illinois  the  surface  is  mainly  plane,  except  on  the  outer 
face  of  the  Iroquois  moraine  and  in  a  belt  a  few  miles  wide  which  follows 
the  south  border  of  the  Kankakee  River,  in  both  of  which  places  there  are 
ridges  and  dunes  of  some  prominence. 

The  ridged  portions  of  the  sand  in  Indiana  occupy  southeastern  Stark, 
much  of  Pulaski,  and  the  central  portions  of  Jasper  cuid  Newton  counties, 
all  of  which  lie  southeast  of  the  Kankakee  marsh,  as  well  as  a  narrow  strip 
on  the  east  and  south  borders  of  the  sand  area  in  Fulton,  Cass,  White,  and 
Jasper  counties.  There  are  also  scattering  ridges  in  the  midst  of  the-  level 
portions  of  the  sand  area  in  that  State. 

The  most  prominent  ridges  are  35  or  40  feet  in  height,  but  the  majority 
are  less  tlian  20  feet,  and  many  are  only  5  or  10  feet.  The  individual 
ridg-es  vary  in  breadth  from  50  feet  or  less  up  to  nearly  one-eighth  mile, 
but  are  usually  about  200  to  300  feet.  Among  the  ridges,  even  where  most 
prominent,  there  are  narrow  strijjs  with  nearh*  plane  surface. 

The  prevailing  trend  of  tlie  ridges  is  usually  easA"  to  deter  nine,  though 
in  places  the  ridges  wind  about  and  interlock,  forming  an  intricate  network. 
Those  on  the  east  border,  in  Pulaski  County,  Indiana,  show  a  tendency  to 
a  north-to-south  trend,  while  those  on  the  south  border  in  Cass,  White,  and 
Jasper  counties,  trend  nearly  east  to  west.  Those  on  the  south  border  of 
the  Kankakee  trend  aliout  witli  tlie  course  of  the  stream,  south  of  west  in 
the  Indiana  portion  and  iiortli  of  wi'st  in  the  Illinois  portion.  Between  the 
ridges  bordering  tin-  Kniiknkee  in   Indiana,  and  those  on  tlie  south  and  east 


LAKE  KANKAKEE.  333 

borders  of  the  sand  ai-ea,  the  trend  is  not  so  easily  systematized.  The  ridges 
there  are  arranged  in  groups  or  strips,  among  which  there  are  extensive 
plane  tracts,  often  bowlder  strewn,  and  having  only  a  thin  sand  coating. 
Some  attempts  to  systematize  these  ridges  and  associated  bowldery  tracts 
have  been  made  both  by  Professor  Chamberlin  and  Professor  Purdue,  but 
without  the  satisfactory  results  which  they  had  sought  to  obtain.^ 

THICKNESS    OF    THE    SAND. 

The  thickness  of  the  sand  varies,  both  because  of  aggregation  in  ridges 
and  because  of  irregularities  of  the  surface  over  which  it  is  spread.  In 
much  of  the  region  within  the  Tippecanoe  drainage  basin  the  sand  is  very 
thin  except  in  the  ridges.  This  condition  prevails  also  over  southern  Jasper 
and  Newton  counties,  Indiana,  and  in  parts  of  Kankakee  and  Will  counties, 
Illinois.  An  extensive  region  on  either  side  of  the  Kankakee  from  eastern 
Iroquois  and  Kankakee  counties,  Illinois,  eastward  to  Marshall  and  St. 
Joseph  counties,  Indiana,  is  covered  Avith  sand  to  a  depth  of  several  feet 
below  the  level  of  the  base  of  the  ridges.  Throughout  much  of  this  region 
wells  are  obtained  without  passing  below  the  sand.  Tlieir  depth  is  shallow, 
being  generally  10  feet  or  less  on  the  flat  tracts,  and  correspondingly  deeper 
on  ridges. 

Averaging  the  available  data  the  sand  apparently  amounts  to  a  contin- 
uous sheet  not  far  from  10  feet  in  depth,  over  the  3,000  square  miles  which 
it  covers,  or  to  5.68  cubic  miles. 

VARIATIONS    IN    COARSENESS. 

The  sand  presents  but  little  variation  in  coarseness.  It  is  usually 
sufficiently  coarse  for  individual  grains  to  be  readily  discerned  by  the 
naked  eye  and  is  seldom  too  coarse  for  plasterers'  use.  Coarse  gravelly 
material  is  found  in  a  ridge  near  Rensselaer  and  in  beaches  on  the  border 
of  the  Illinois  in  Grundy  County,  Illinois.  There  are  also  gravel  plains  on 
the  border  of  the  Valparaiso  and  Maxinkuckee  moraines  in  Laporte  and  St. 
Joseph  counties.  With  these  exceptions  it  is  rare  to  find  in  these  deposits 
a  pebble  as  coarse  as  a  buckshot. 

In  the  Iroquois  Basin  in  Newton  County,  Indiana,  and  also  in  parts  of 
Iroquois  County,  Illinois,  thin  beds  of  silt  about  as  fine  as  loess  and  much 

'  Professor  Purdue  contemplates  further  study  of  the  region  to  determine  whether  it  is  possible 
to  bring  order  out  of  the  present  appareut  lack  of  system. 


334  THE  ILLINOIS  GLACIAL  LOBE. 

resemljling  it  in  appearance  are  j)resent  within  tlie  limits  of  the  sandy 
ridges.  These  deposits  are  somewhat  calcareous  and  in  places  caiTy  small 
nodules  of  lime.  The  sand  appears  to  graduate  horizontally  into  the  loess- 
like silt  in  passing  westward  down  the  Iroquois  Valley  from  Jasper  County 
into  Newton  County,  Indiana,  also  in  passing  westward  from  the  moraine 
in  eastern  Iroquois  County,  Illinois,  into  the  lower  districts  along  the 
Iroquois  Valley.  In  a  few  places  loess-like  silt  was  found  among  the  sand 
ridges  on  the  immediate  border  of  the  moraine.  With  these  exceptions 
there  is  but  little  silt  or  clayey  material  present.  The  flat  areas  are  often 
sandy,  and  heavy  beds  of  peat  or  surface  muck  are  rare.  In  one  locality 
near  Reynolds,  Indiana,  beds  of  peaty  muck  containing  vegetal  remains 
are  reported  to  underlie  the  sand  ridg-es,  thus  denoting  an  interval  of  emer- 
gence or  exposure  to  atmospheric  action  between  the  Avithdrawal  of  the  ice 
sheet  and  the  spreading  out  of  the  sand  deposits.  Well  autlienticated 
instances  were  found  only  along  the  south  border  of  the  sand  area,  and 
their  significance  is  not  understood. 

INTERPRETATIONS. 

The  limits  of  the  sand  area  on  the  north,  east,  and  southeast  being 
found  in  moraines,  the  question  naturally  arises  whether  the  sand  is  not  an 
outwash  from  one  or  more  of  the  ice  lobes  which  formed  these  bordering 
moraines.  Furthermore,  the  direction  of  the  retreat  of  the  margin  being 
such  as  to  gradually  uncover  this  area  from  its  western  toward  its  eastern 
and  northern  borders,  it  needs  to  be  determined  whether  the  sand-covered 
area  may  not  have  been  gradually  extended  from  the  southwest  toward  the 
northeast. 

Upon  examining  into  the  connection  between  the  sand  deposits  and  the 
moraines  it  is  found  that  in  the  northeast  part  of  the  area  tlie  moraines  have 
a  gravelly  outwash,  but  this  does  not  oppose  the  view  just  suggested,  since 
the  gravel  seems  to  graduate  into  sand  upon  passing  from  the  moraines  into 
the  sand-covered  area.  There  is  also  a  change  to  sand  along  the  innnediate 
borders  of  the  moraine,  either  upon  passing  south  along  tlie  Maxinkuckee 
moraine,  or  west  along  the  ^^alparaiso  moraine. 

Examining  into  the  sectmd  question,  it  is  found  tliat  the  sand  ridges  in 
places  alternate  with  bowlder  belts  in  such  manner  as  to  lend  some  support 
to  the  view  that  the  sand  was  deposited  in  coiuKH-tSnu  with  the  northeast- 


LAKE  KANKAKEE.  335 

ward  retreat  of  the  ice  margin.  The  bowlder  belts  may  mark  the  successive 
ice  margins.  In  this  case  the  ridging  of  the  sand  may  be  due  entirely  to 
wind  action,  or  the  ridges  may  be  esker-like  accumulations  formed  beneath 
a  nearly  stagnant  ice  sheet.  Perhaps  a  systematic  relation  between  the 
bowlder  belts  and  the  sandy  areas  may  yet  be  worked  out.  At  present  the 
courses  of  the  bowlder  belts  seem  less  systematic  than  would  be  expected 
under  this  hypothesis,  so  that  this  inatter  is  still  in  question.  The  presence 
of  beds  of  peat  and  muck  at  the  base  of  the  sand,  which  is  a  consjiicuous 
feature  in  the  vicinity  of  Reynolds,  Indiana,  perhaps  opposes  this  interpreta- 
tion, since  it  calls  for  an  intei'val  of  emergence  with  exposure  to  atmospheric 
action  between* the  withdrawal  of  the  ice  sheet  and  the  deposition  of  the 
sand.  The  development  of  the  peaty  muck  may,  however,  not  prove  fatal 
to  this  interpretation,  since  it  is  apparently  limited  in  extent  and  demands 
no  great  length  of  time.  The  outwash,  where  most  vigorous,  may  have 
caused  the  sand  to  encroach  upon  peat  bogs  in  the  outlying  districts.  In 
some  cases  it  is  probable  that  wind  may  have  drifted  the  sand  in  such  man- 
ner as  to  bury  the  peat  bogs.  That  wind  action  has  been  influential  in 
heaping  up  the  sand  throughout  this  area  can  scarcely  be  questioned. 

An  alternative  interpretation  to  that  of  a  gradually  formed  glacial  out- 
wash  at  the  margins  of  receding  ice  lobes  is  found  in  the  hypothesis  that  this 
sand-covered  region  is  the  bottom  of  an  extensive  lake  in  which  the  waves 
washed  the  till  sheet  and  formed  the  sand.  This  hypothesis  need  not  require 
that  the  entire  sandy  area  was  at  any  one  time  covered  by  a  lake.  It  may 
also  admit  the  application  of  the  hypothesis  of  glacial  outwash  in  explanation 
of  the  gravel  and  sand  on  the  east  and  north  borders,  where  the  altitude  is 
greater  than  on  the  south  and  west  borders  of  the  sand-covered  area.  It 
would  differ  from  the  former  hypothesis  in  requiring  a  larger  amount  of 
static  water  and  greater  influence  of  waves.  Were  the  upper  or  southern 
ridge  of  sand  on  the  south  border  of  the  sand-covered  region  horizontal  or 
even  slightly  tilted  toward  the  east,  it  would  give  support  to  this  hypothesis, 
for  the  ridge  certainly  bears  a  strong  resemblance  to  a  lake  beach,  but  the 
fluctuations  in  level  (from  675  to  750  feet  above  tide)  seem  too  great  to  be 
accounted  for  by  the  warping  of  an  originally  horizontal  line,  and  especially 
since  the  departui-e  from  the  horizontal  is  in  the  form  of  wave-like  oscil- 
lations instead  of  a  regular  uplift.  Furthermore,  the  nearly  parallel  ridge 
a  few  miles  to  the  north  does  not  show  similar  warping.     The  supposed 


336  THE  ILLINOIS  GLACIAL  LOBE. 

extensive  lake,  thei'ef'ore,  can  scarcely  have  had  a  level  on  its  south  border 
higher  than  the  lower  parts  of  the  ridge  that  forms  that  border  of  the  sandy 
area,  or  675  to  685  feet  above  tide.  This  is  about  the  elevation  of  the 
sandy  ridge  which  leads  from  Monon  Creek  west  to  Percy  Junction.  It  is 
also  about  the  elevation  of  the  eastern  end  of  the  Kankakee  marsh  at  its 
junction  with  the  gravel  plains  bordering  the  Valparaiso  and  Maxinkuckee 
moraines.  It  is  fully  50  feet  lower  than  the  highest  parts  of  the  sand- 
covered  area,  not  only  those  on  the  east  borders  but  also  points  in  the 
interior.  A  lake  with  this  elevation  could  have  had  but  shallow  depth 
throughout  much  of  the  Indiana  portion,  and  interrupted  as  it  must  have 
been  bv  numerous  islands  it  could  scarcely  have  allowed  wave  action  of 
much  strength.  It,  therefore,  seems  improbable  that  lake  waves  should 
have  caused  the  formation  and  deposition  of  much  of  the  sand. 

The  hypothesis  of  glacial  outwash  as  the  chief  contributor  of  sand,  and 
of  wind  as  an  important  distributor,  apparently  needs  to  be  supplemented 
by  that  of  the  presence  of  a  shallow  body  of  water  over  much  of  the  sandy 
area  during  and  for  some  time  subsequent  to  the  retreat  of  the  ice  lobes. 
Even  now  much  of  the  Kankakee  marsh  is  covered  throughout  the  greater 
part  of  the  year  by  a  broad  shallow  body  of  water  in  which  the  cm-rent  is 
very  sluggish  and  which  resembles  a  lake  more  than  a  stream. 

The  western  portion  of  this  sandy  area  needs  separate  interpretation, 
since  the  sand  deposits  there  appear  to  have  had  a  history  somewhat  inde- 
pendent of  the  eastern  portion. 

As  above  noted,  the  sand  deposits  on  the  outer  or  western  face  of  the 
Iroquois  moraine  in  eastern  Iroquois  County  in  all  probability  were  largely 
contributed  by  the  ice  sheet  at  the  time  that  moraine  was  forming.  This 
being  the  case,  they  antedate  the  deposits  found  east  of  that  moraine.  In 
case  the  correlation  of  the  Iroquois  moraine  with  the  bowldery  strip  along 
the  south  side  of  the  Kankakee  in  Will  and  Kankakee  counties,  Illinois,  is 
sustained,  the  sandy  belts  found  in  close  association  Avith  these  bowlders 
would  perhaps  be  of  the  same  age  as  those  of  northeastern  Iroquois  County, 
Illinois,  with  which  they  connect  in  southeastern  Kankakee  County.  It 
seems  probable  that  a  shallow  lake  occupied  northern  Iroquois  Comity 
at  that  time.  Possibly  it  stood  as  high  as  the  sand  ridge  which  leads 
through  Onarga  and  Ridgeville  (675  feet  above  tide),  though  it  seems  more 
probable  that  it  had  slirunlc  to  a  lower  level,  since  there  a23pears  to  have 


LAKE  KANKAKEE.  337 

been  at  that  time  no  obstacle  to  a  discharge  thi-ough  the  Kankakee  Basin  to 
the  Illinois. 

The  basin  at  the  head  of  the  Illinois  apparently  held  a  lake  for  a  longer 
period  than  the  remainder  of  the  region  under  discussion.  In  all  proba- 
bility a  ponding  of  waters  in  front  of  the  retreating  ice  sheet  occurred  imme- 
diately upon  the  withdrawal  of  the  ice  sheet  from  the  Marseilles  moraine. 
At  first  the  waters  may  have  found  escape  through  the  gaps  in  the  moraine 
above  noted,  which  stand  at  about  the  level  of  the  inner  border  of  the 
moraine,  at  an  altitude  640  or  650  feet  above  tide.  The  gap  along  the  line 
of  the  present  Illinois  River  seems  to  have  eventually  di-awn  away  the  drain- 
age from  the  other  gaps.  E\ddence  that  lake  water  stood  high  enough  to 
discharge  thi'ough  these  gaps  is  found  in  deposits  of  sand  which  coat  the  till 
for  some  distance  back  from  each  of  them,  and  in  silt  deposits  spread  more 
widely  over  the  basin;  also  in  a  greater  smoothness  of  surface  below  the 
level  of  these  gaps  than  above  that  level. 

The  outlet  across  the  Marseilles  moi-aine  and  districts  to  the  west  along 
the  line  of  the  Illinois  River  was  probably  cut  down  very  slowly,  since 
much  rock  has  been  excavated  by  it.  Even  as  late  as  the  time  the  Valpa- 
raiso moraine  was  formed  the  outlet  had  not  been  cut  down  sufficiently  to 
drain  the  lake  in  the  basin  at  the  head  of  the  Illinois.  As  already  noted, 
terraces  on  the  Des  Plaines  River,  heading-  in  the  Valpai-aiso  moraine,  which 
were  formed  in  connection  with  the  moraine,  indicate  that  a  lake  stood  in 
this  basin  at  the  head  of  the  Illinois  while  they  were  forming.  These  ter- 
races and  also  beaches  in  the  Morris  Basin  indicate  that  its  level  was  about 
560  feet  above  tide,  or  60  feet  above  the  present  head  of  the  Illinois  River. 

This  stage  of  the  lake  in  the  Morris  Basin  having  been  thus  connected 
with  the  Valparaiso  moraine,  it  is  evident  that  the  level  Avas  equally  high 
in  the  earlier  stage,  when  the  outwash  of  sand  occurred  on  the  lower 
Iroquois  and  lower  Kankakee.  The  lake  level  extended  up  the  Kankakee 
Valley  about  as  far  as  Braidwood,  where  the  sand  dunes  set  in.  It  seems 
not  improbable  that  drainage  conditions  were  such  as  to  produce  only  a 
sluggish  flow  of  water  in  the  lower  Kankakee  at  that  time,  similar  to  the 
present  sluggish  current  of  the  upper  portion  of  that  stream.  In  this  con- 
nection it  may  be  remarked  that  it  is  doubtful  if  any  ajDpreciable  excavation 
of  the  Kankakee  Valley  below  Momence  had  occurred  up  to  the  time  of 
the  formation  of  the  Valparaiso  moraine.     It  was  subsequent  to  this  that 

MON  XXXVIII 22 


338  THE  ILLINOIS  GLACIAL  LOBE. 

the  Illinois  became  an  outlet  for  the  lai'ge  amount  of  water  discharged  from 
Lake  Chicago,  and  which  caused  a  rapid  deepening  of  the  outlet  and  greatly 
hastened  the  draining  of  the  lake  in  the  Morris  Basin.  During  a  portion  of  the 
time  that  the  Chicago  outlet  was  in  operation  the  Kankakee  afforded  a  line 
of  discharge  for  the  St.  Joseph  River  and  the  waters  poured  into  it  from  the 
melting  Saginaw  lobe,  which  probably  accounts  for  much  of  the  erosion 
accomplished  along  the  borders  of  that  stream  and  a  measurable  i^art  of 
that  along  the  Illinois.  This  deepening  of  channel  at  the  mouth  of  the 
Kankakee  has  led  to  an  excavation  on  the  lower  portion  of  the  Kankakee, 
which  has  progressed  no  farther  up  the  valley  than  the  rock  barrier  at 
Momence.  The  upper  portion  is  still  flowing  at  the  low  gradient  of  its 
large  predecessor. 

Reviewing  the  above  observations,  the  interpretation  which  seems  to 
best  apply  to  this  region  admits  only  lakes  of  small  extent  or  shallow  depth, 
and  opposes  the  occupancy  of  the  entire  sandy  area  by  water  at  an}''  one 
time.  Glacial  lakes  held  in  the  Morris  Basin  and  the  Iroquois  Basin  ma)^, 
at  their  maximum  extent,  have  formed  a  sing'le  body  of  water  with  an  outlet 
or  outlets  about  650  feet  above  tide.  This  lake  level  had  probably  become 
lowered  somewhat  before  the  sand  deposits  were  made  in  northeastern  Iro- 
quois County  and  along  the  lower  course  of  the  Kankakee,  and  possibly 
may  have  been  cut  down  nearly  to  the  level  of  the  uppermost  well-defined 
beach  in  the  Morris  Basin  (560  feet).  The  sand  deposits  in  the  upper 
Kankakee  region  and  neighboring  districts  on  the  south  seem  best  explained 
as  glacial  outwash  made  during  the  withdrawal  of  the  ice  sheet  to  tlie  posi- 
tion marked  by  the  Valparaiso  and  Maxinkuckee  moraines,  and  probably 
continued  during  the  formation  of  those  moraines.  The  upper  Kankakee 
Basin  seems  then  to  have  been  occupied  only  by  a  shallow  body  of  water 
which  may  have  extended  but  little  beyond  the  limits  of  the  Kankakee 
marsh.  The  method  of  formation  of  the  well-defined  south  border  of  the 
sand  area  in  western  Indiana,  with  its  fluctuations  in  elevation,  is  as  yet  not 
understood.  The  distribution  of  the  sand  ridges  and  their  alternation  with 
bowldery  belts,  both  in  the  Indiana  district  and  along  the  south  border  of 
the  Kankakee,  are  features  which  do  not  lend  themselves  to  a  ready  solu- 
tion.    Indeed,  tlie  entire  interpretation  is  less  definite  than  could  be  desired. 


THE  LATE  WISCONSIN  DEIFT  SHEETS.  339 

SECTIOlSr  IV.    THE  VALPARAISO  MORAII«riC  SYSTEM. 

The  morainic  system  discvissed  under  this  name  was  brought  to  notice 
by  Chamberlin  in  an  early  report  of  this  Siirvey,  under  the  title  "The 
Moraine  of  the  Lake  Michig-an  Glacier."  ^  Inasmuch  as  the  morainic 
system  was  formed  by  an  ice  lobe  which  was  almost  confined  to  the  basin 
of  Lake  Michigan,  it  seems  convenient  to  speak  of  it  as  the  product  of  the 
Lake  Michigan  glacier  rather  than  to  appl}"  the  more  comprehensive  term, 
Illinois  Glacial  Lobe;  and  the  drift  is  conveniently  referred  to  as  the  Lake 
Michigan  drift. 

The  course  of  this  morainic  system  as  outlined  in  the  Third  Annual 
Report  was  chiefly  traced  from  northeastern  Illinois  around  the  head  of 
Lake  Michigan  by  Prof  L.  C.  Wooster,  who  subsequently  examined  it  in 
more  detail.  Chamberlin  gave  it  considerable  study  in  connection  with  his 
investigations  faiiher  north  and  east.  The  writer's  studies  began  after  the 
publication  of  that  report.  He  has  given  this  morainic  system  but  little 
attention  in  northwestern  Indiana,  but  has  made  a  somewhat  detailed  study 
of  it  in  southwestern  Michigan  and  in  portions  of  northeastern  Illinois  not 
covered  by  Wooster. 

The  name  Valparaiso,  taken  from  a  cit}'  of  that  name  located  on  a 
very  prominent  portion  of  the  morainic  system  in  northwestern  Indiana, 
was  suggested  by  Wooster  in  a  manuscript  report  and  has  been  used  by 
the  writer  in  previous  papers  which  touch  upon  this  system. 

DISTRIBUTION. 

As  pointed  oat  by  Chamberlin,  this  morainic  system  "may  be  likened 
to  an  immense  U,  embracing  the  great  lake  between  its  arms."  It  has  a 
length  from  north  to  south  of  over  100  miles,  if  portions  coalesced  with 
older  moraines  on  its  outer  border  be  included.  The  breadth  of  the  lobe 
averages  nearly  100  miles.  .  The  parallelism  of  the  morainic  system  to  the 
shore  of  Lake  Michigan  is  one  of  its  most  striking  features.  In  the  portion 
examined^  by  the  wi-iter,  which  lies  south  of  the  latitude  of  the  Illinois  and 
Wisconsin  State  line,  the  inner  border  is  usually  less  than  15  miles  and  at 
its  closest  approach  is  only  about  6  miles  distant  from  the  lake,  and  this  close 
parallelism  is  known  to  be  continued  still  farther  north.  In  this  portion 
the  breadth  of  the  morainic  system  ranges  from  5  or  6  miles  up  to  nearly 

'  Third  Annu.^1  Report  U.  S.  Geol.  Survey,  1881-82,  pp.  322-325. 


340  THE  ILLINOIS  GLACIAL  LOBE. 

20  miles.  It  i.s  narrowest  just  south  of  the  Michigan  and  Indiana  State 
line  and  broadest  in  the  vicinity  of  the  Indiana  and  Illinois  State  line. 
The  glacial  map  (PI.  VI)  sets  forth  its  variations  in  width. 

In  northern  Illinois  this  morainic  system  becomes  merged  with  older 
moraines  in  the  composite  belt  already  discussed,  but  it  evidently  finds  its 
continuation  northward  along  the  inner  or  eastern  border  of  that  belt  as  far 
as  the  peninsula  between  Green  Bay  and  Lake  Michigan. 

The  Valparaiso  morainic  system  in  Michigan  is  made  to  include  the 
entire  bulky  morainic  belt  of  Lake  Michigan  drift,  from  the  Grand  River 
Valley  southward,  though  it  consists  in  places  of  two  or  more  constituent 
ridges.  These  ridges  coalesce  and  separate  by  turns,  but  nowhere  become 
so  distinctly  separated  as  to  appear  to  merit  individual  names  and  separate 
descriptions.  This  belt  of  Lake  Michigan  drift  is  distinct  from  moraines  of 
the  Saginaw  lobe  in  Berrien  and  southern  Van  Buren  counties,  but  in 
northern  Van  Buren  County  it  becomes  so  closely  associated  with  the 
Saginaw  moraines  that  the  line  of  separation  can  be  made  out  only  upon 
close  study.  The  moraines  remain  closely  associated  from  Van  Buren 
County  northward  at  least  as  far  as  Grand  Rapids,  beyond  which  the  writer 
has  not  carried  his  investigations.  Investigations  by  the  Michigan  survey 
indicate  that  later  moraines  may  conceal  it  in  the  northern  part  of  the 
Southern  Peninsula. 

BORDER  BETWEEN  THE  LAKE  MICHIGAN  AND  SAGINAW  BAY  LOBES. 

The  nature  of  the  border  line  between  this  morainic  system  and  the 
neighboring  morainic  system  of  the  Saginaw  lobe  merits  special  attention. 
The  description  begins  in  southern  Allegan  County  and  is  carried  southward 
to  northern  Indiana. 

The  eastern  border  of  the  Valparaiso  system,  as  shown  in  PI.  XV,  is 
apparently  found  in  the  eastern  tier  of  townships  in  Allegan  County  from 
the  northeast  corner  of  the  county  southward  to  the  vicinity  of  Mouteith. 
The  moraine  here  has  an  overwash  gravel  plain  along  its  eastern  border 
occupying  the  western  half  of  Martin  and  central  part  of  Wayland  town- 
ships. This  plain  shows  a  perceptible  eastward  slope  away  from  the  moraine. 
Alonff  its  east  border  there  is  a  moraine  of  the  Saginaw  lobe.  This  moraine 
swings  westward  just  south  of  Monteith  and  the  two  ice  lobes  appear  to 
have  come  into  close  contact  for  a  few  miles  south  from  that  point.  The 
Saginaw  movement  was  sufficiently  strong,  not  onl}^  to  meet  the  ice  lobe  on 


U.S. GEOLOGICAL  SURVEY- 


MONOGRAPH  XXXVIII  PL. XV 


43°- 

1" 


LEGEND  GrmtdHi 

Moraiiies  of  Late  ^acMg'an.  Glacier 


Moraines  of  Saglaaw  Glacier 
TiU  plains 

Gravel  and  sand  plains 
Extent  of  Lake  Chicago 


Scale   of  miles 

5  10  15  20  25 


—  Note: 

Son\e  of  ihe  district  represented  in  tKe 
northeast  part  of  the  map  has  not  been 
examined  andis  therelbre  left  uncolored 
The  precise  limits  of  Lake  Chicago  in 
southern  AUeean  andnortheruVanBuren 


counties  ai-e  i\ol  determined 


nrajjifP- 


JULIUS  BfEN  &  CO-LITH    N> 


PLEISTOCENE  MAP  OF  SO UTHWT: STERN  MICHIGAN 

Hi'  FRANK  LE\^RETT 

1898. 


THE  VALPARAISO  MOEAINIC  SYSTEM.  341 

the  west,  but  to  extend  the  border  between  the  lobes  several  miles  to  the 
west.  This  border  assumes  a  nearly  east  to  west  coiu'se,  across  Otsego  and 
Trowbridge  townsliips.  In  the  latter  township  it  has  the  form  of  a  double 
ridge  with  only  the  Kalamazoo  River  between  the  two  members.  A  till 
plain  tits  closely  about  the  border  of  the  north  member  on  the  west  and 
north,  which  rises  toward  the  morainic  ridge,  apparently  indicating  that  the 
Lake  Michigan  movement  extended  to  this  ridge.  Similarly  the  south 
member  is  bordered  by  a  plain  on  the  south  and  east,  which  rises  toward 
the  ridge  and  indicates  that  it  was  formed  by  the  Saginaw  movement. 

The  Saginaw  movement  apparently  extended  only  to  the  western  part 
of  Trowbridge  Township,  for  the  ridge  on  the  south  side  of  the  Kalamazoo 
River  swings  around  on  the  west  and  south  border  of  the  till  plain  just 
referred  to.  The  double  I'idge,  which  in  Otsego  and  Trowbridge  townships 
trends  toward  the  west,  here  becomes  combined  into  a  single  belt  and 
swings  around  through  Cheshire  Township  to  a  southerly  course.  It  pre- 
sents sloping  till  plains  on  each  side  rising  toward  it.  As  the  combined 
morainic  belt  enters  Van  Buren  County  it  again  becomes  separated.  The 
Saginaw  moraine  turns  to  the  east,  crossing  the  northern  part  of  Pine 
Grove  Township,  while  the  moraine  of  the  Lake  Michigan  lobe  bears 
nearly  due  south  tlxrough  the  eastern  part  of  Bloomingdale  Township.  An 
overwash  gravel  plain  common  to  the  two  lobes,  covering  5  or  6  square 
miles,  separates  the  two  moraines  in  western  Pine  Grove  Township,  while 
each  moraine  has  a  till  plain  fitting  about  its  opposite  border.  In  each  ease 
the  till  plain  rises  toward  the  moraine  which  it  borders. 

In  the  townships  south  of  Bloomingdale  and  Pine  Grove  (Waverlj^ 
and  Almena)  both  moraines  are  obscure  near  their  line  of  junction,  there 
being  instead  an  extensive  swamp,  which  borders  Pawpaw  River  and  is 
known  as  the  Pawpaw  Swamp,  in  which  only  occasional  clusters  of  knolls 
appear.  The  Lake  Michigan  movement  apparently  extended  about  to  the 
border  between  Waverly  and  Almena  townships,  for  the  till  plain,  which 
farther  jaorth  lies  west  of  the  eastern  or  outer  member  of  the  Lake  Michi- 
gan movement,  extends  about  to  this  line  and  borders  the  swamp  just 
mentioned  on  the  west.  The  Saginaw  movement,  which  ^^roduced  a  bulky 
moraine  in  Pine  Grove  Township,  has  scarcely  any  morainic  features  in 
the  township  on  the  south.  The  till  plain,  which  in  Pine  Grove  Township 
lies  east  of  the  prominent  morainic  ridg-e,  continues  southward  along  the 
east  border  of  the  Pawpaw  Swamp. 


342  THE  ILLINOIS  GLACIAL  LOBE. 

Immediately  west  of  the  -sdllage  of  Pawpaw,  at  the  south  border  of 
the  Pawpaw  Swamp,  the  Lake  Michigan  moraine  again  becomes  prominent. 
South  of  this  latitude  the  Saginaw  and  Lake  Michigan  movements  appar- 
ently lacked  a  few  miles  of  meeting,  and  the  interval  is  filled  with  a  great 
gravel  deposit  through  which  the  Dowagiac  River  has  its  course.  The  gravel 
j)lain  descends  toward  the  river  from  either  border.  It  is  therefore  a  double 
outwash,  that  on  the  west  being  the  outwash  from  the  Lake  Michigan  lobe 
and  that  on  the  east  from  the  Saginaw  Bay  lobe.  The  gravel  plain  formed 
as  an  outwash  from  the  Lake  Michigan  lobe  is  characterized  by  numerous 
lakelets,  many  of  which  are  without  surface  outlet.  The  basins  which  they 
occupy  are  so  deep  that  the  water  surface  of  the  lakes  is  in  some  cases  40 
or  50  feet  below  the  general  level  of  the  gravel  plain  on  their  borders. 

Immediately  west  of  Niles  is  a  prominent  morainic  ridge  which  extends 
southwestward  into  Indiana  and  there  turns  south  and  dies  away  in  the 
plain  at  the  head  of  the  Kankakee  River.  It  is  slightly  outside  the  regular 
border  of  the  Valparaiso  moraine  and  is  separated  from  it  by  a  narrow  valley- 
like depression  occupied  for  a  few  miles,  between  Niles  and  Buchanan, 
by  the  southwest  flowing  portion  of  the  St.  Joseph  River.  This  moraine 
belongs  perhaps  to  the  Saginaw  series,  for  its  trend  harmonizes  more  closely 
with  that  of  the  Saginaw  moraine  east  of  it  than  with  the  Valparaiso  moraine 
west  of  it.  Furthermore,  its  surface  bowlders  apparently  bear  more  resem- 
blance to  those  found  in  the  Saginaw  moraines  than  those  on  the  Valparaiso 
moraine.  The  moraine  is  accordingly  discussed  in  connection  with  the 
Saginaw  moraines  in  another  report  now  in  preparation.  A  morainic  tract 
in  the  northwest  township  of  Cass  County  is  also  discussed  in  that  report 
as  a  possible  Saginaw  moraine. 

From  the  State  line  of  Michigan  and  Indiana  the  Valparaiso  moraine 
bears  southwestward  and  the  neighboring  Saginaw  moraine  (the  Maxin- 
kuckee)  bears  southward  while  the  broad  Kankakee  marsh  with  its  border- 
ing gravel  plains  occupies  the  interval  between  them. 

Thus  it  appears  that  the  two  ice  lobes  in  places  had  margins  so  widely 
separated  that  each  ])rod;'iced  a  gravel  apron  of  its  own  on  its  outer  margin; 
in  other  places  a  single  overwash  apron  was  produced,  as  in  Pine  Grrove 
Township,  Van  Buren  County,  and  Martin  Township,  Allegan  Count}'';  in 
other  places  the  two  glaciers  formed  moraines  side  by  side,  with  no  over- 
wash  apron  between,  as  in  Trowbridge  Township,  where  the  Kalamazoo 
River  flows  between  tliein;    in  Cheshire  Township  a  single  moraine  was 


THE  VALPARAISO  MORAINIC  SYSTEM.  343 

produced  by  the  two,  and  we  find  north  of  Pawpaw,  the  last  extreme,  a 
place  where  neither  glacier  produced  a  definite  ridge  at  the  point  where  the 
two  lobes  came  in  contact. 

RANGE    IN    ALTITUDE. 

The  inner  border  of  the  Valparaiso  morainic  system,  so  far  as  examined, 
presents  but  little  range  in  altitude,  being  usually  between  650  and  690  feet 
above  tide,  or  70  to  110  feet  above  the  level  of  Lake  Michigan.  From  the 
inner  border  there  is  usually  a  rise  of  at  least  100  feet,  and  in  places  of  200 
feet  or  more,  to  the  main  crest  of  the  morainic  system.  This  crest  in  the 
Illinois  portion  ranges  from  about  750  feet  up  to  nearly  900  feet  above  tide, 
being  highest  in  the  vicinity  of  Lake  Zurich,  in  southern  Lake  County,  and 
lowest  on  the  borders  of  the  Des  Plaines  River,  in  Will  County.  In  the 
Indiana  portion  the  crest  ranges  from  about  750  feet  in  Lake  County  to 
nearly  900  feet  in  Laporte  County.  In  the  Michigan  portion  the  crest  is 
750  to  800  feet  in  the  vicinity  of  the  St.  Joseph  River  and  northward  nearly 
to  the  line  of  Allegan  and  Van  Buren  counties.  But  in  Allegan  Coiinty  it 
presents  more  range,  the  highest  points  being  fully  900  feet,  while  the  low 
points  near  the  Kalamazoo  River  rise  but  little  above  700  feet. 

On  the  outer  border  of  the  morainic  system  the  altitude  is  generally 
much  higher  than  on  the  inner  border,  though  in  Kankakee  and  southern 
Will  counties,  Illinois,  the  difference  in  the  elevation  of  the  inner  and  outer 
borders  is  only  a  few  feet.  The  difference  is  also  slight  in  Lake  and  west- 
ern Porter  counties,  Indiana.  In  the  ^dcinity  of  the  Wisconsin  line  and 
southward  as  far  as  Elgin,  Illinois,  the  outer  border  stands  between  750 
and  775  feet.  It  declines  to  about  700  feet  at  Naperville,  Illinois,  and 
to  about  650  feet  in  southwestern  Will  County,  Illinois  It  rises  thence 
gradually  eastward  up  the  Kankakee  Valley,  reaching  700  feet  in  eastern 
Porter  County,  Indiana.  There  is  then  a  more  rapid  rise  and  an  altitude 
of  about  800  feet  is  attained  in  the  vicinity  of  Laporte,  Indiana.  This 
altitude  is  maintained  eastward  from  Laporte  to  the  border  of  St.  Joseph 
County,  Indiana.  A  descent  there  begins  toward  the  St.  Joseph  River 
and  the  altitude  decreases  to  about  710  feet  on  the  borders  of  that  stream 
north  of  Niles,  Michigan.  In  j^assing  northward,  up  the  Dowagiac  Valley, 
the  altitude  alono-  the  outer  border  of  this  morainic  svstem  increases  to 
about  800  feet  in  Keeler  and  Hamilton  townships,  Van  Buren  County, 
Michigan.     It  declines  again  to   about  700  feet  at  the   Pawpaw  marsh  in 


344 


THE  ILLINOIS  GLACIAL  LOBE. 


Alineiia  Township,  but  rises  to  800  feet  at  the  gravel  plain  in  western  Pine 
Grove  Township.  At  the  Kalamazoo  River  it  is  only  about  700  feet,  but 
on  the  gi'avel  plain  in  Mai'tin  and  Wayland  townships,  Allegan  County,  its 
altitude  is  800  to  850  feet.  The  following  table  of  elevations  taken  from 
the  railway  profiles  which  cross  this  morainic  system,  is  designed  to 
set  forth  the  altitude  of  the  inner  border,  the  main  crest,  and  the  outer 
border.  Numerals  inclosed  in  parentheses  represent  the  general  elevation 
of  the  crest  in  the  \'icinity  of  the  railway  line  in  places  where  the  railway 
either  makes  a  deep  cut  or  passes  the  crest  along  a  drainage  line. 

Table  of  elevations  on  Valparaiso  moraine. 


Elgin,  Joliet  and  Eastern,  in  Lake  County,  111  — 
\\  isconsiu  Central 

Chicago,  Milwaukee  and  St.  Paul 

Chicago  and  Northwestern  (Wisconsin  Division)  . 

Chicago  and  Northwestern  (Omaha  Division) 

Chicago,  Burlington  and  Quincy 

Wabash 

Chicago,  Rock  Island  and  Pacific 

Illinois  Central  

Chicago  and  Eastern  Illinois 

Louisville,  New  Albany  and  Chicago  (Chicago 
Division)  

Pan  Handle 

Chicago  and  Erie 

Pittsburg,  Fort  Wayne  and  Chicago 

Chicago  and  Grand  Trunk 

Baltimore  and  Ohio 

Lake  Shore  and  Mithigau  Southern 

Lake  Erie  and  Western 

Chicago  and  Western  Michigan 

Vaudalia  Line 

Michigan  Central 

Chicago  and  Western  Michigan 

Kalamazoo  and  South  Haven  Division  of  Michi- 
gan Central 


Inner 
border. 


Feet. 
720 
683 
646 
650 

641 

646 

665 

630 

650 
632 

640 
650 
650 
660 
650 
670 
675 
685 
690 
680 
080 
670 

680 


Crest. 


Outer 
border. 


\ 


Feet. 

880 
823 

812 
867 
760 

(790)  \\ 
763 
712 
(750) 
725 
(750) 
806 
777 

740± 
740± 
760± 
775J; 
825 
(850) 
831 
863 
863 
(750) 
(750) 
785 

825 


Feet. 
770 

778 
768 
772 

750 

700 

a  680 

a  680 

a  710 
a  713 

660 
673 
685 
730 
770 
775 
800 
790 
775' 
730 
730 
710 

800 


a  Outer  border  of  main  ridge. 


THE  VALPARAISO  MOEAINIO  SYSTEM.  345 


SURFACE   CONTOURS. 


The  Valparaiso  morainic  system  is  nearly  as  complex  as  the  Blooming- 
ton  and  Champaign  systems,  but  it  does  not  admit  of  separation  into  such 
distinct  ridges.  Around  the  southwestern  end  of  the  loop  in  Dupage  and 
Will  counties,  Illinois,  it  is  possible  to  trace  three  distinct  crest  lines.  Usu- 
ally, however,  there  are  but  two,  and  in  places  but  a  single  crest.  Where 
most  cleal-ly  separable  into  distinct  ridges,  there  is  one  ridge  which  much 
exceeds  the  others  in  bulk,  and  constitutes  the  main  ridge  of  the  system. 
Where  not  clearly  separable,  the  minor  ridges  either  become  coalesced  with 
the  main  ridge  or  present  imperfect  ridging. 

In  the  vicinity  of  the  Wisconsin  and  Illinois  line  and  thence  southward 
through  Lake  County,  Illinois,  the  main  ridge  occupies  the  eastern  ^^art  of 
the  system.  In  the  western  part  the  ridging  is  less  definite,  though  the 
morainic  expression  is  in  places  more  pronounced  than  in  the  eastern  part. 
Upon  passing  southward  across  northwestern  Cook  County  a  minor  ridge 
makes  its  appearance  on  the  eastern  slope,  and  is  separated  from  the  main 
ridge  by  the  valley  of  Salt  Creek.  This  ridge  continues  across  Dupage 
County.  The  main  ridge  covers  nearly  the  entire  width  of  the  system  in 
northwestern  Cook  County,  but  in  Dupage  County  there  is  not  only  the 
minor  ridge  on  the  eastern  or  inner  border,  but  also  one  on  the  western  or 
outer  border  of  the  system.  The  valley  of  East  Dupage  River  separates 
the  main  ridge  from  the  minor  ridge  west  of  it. 

From  the  vicinity  of  the  Des  Plaines  River  eastward  to  the  border  of 
Indiana  the  three  ridges  just  mentioned  are  distinctly  traceable,  the  main 
ridge  occupying  the  central  part  of  the  system  and  the  minor  ridges  the 
outer  and  inner  borders.  The  ridge  on  the  outer  border  is  in  places  sepa- 
rated from  the  main  ridge  by  a  narrow  plain,  but  is  closely  associated  with 
it  near  the  State  line  and  also  from  the  Des  Plaines  River  northward.  The 
interval  between  the  main  ridge  and  the  minor  ridge  on  the  inner  border  is 
narrow  and  generally  nearly  as  undulating  as  the  ridges.  Near  Matteson, 
however,  a  small  plane  tract  separates  the  two  ridges. 

In  Lake  County,  Indiana,  the  ridge  on  the  north  or  inner  border  of 
the  morainic  system  becomes  nearly  as  prominent  as  the  main  ridge,  and 
constitutes  the  water  parting  between  the  Kankakee  River  system  and 
Lake  Michigan.  It  also  constitutes  the  water  parting  in  a  few  places  west 
of  the  State  line. 


346  THE  ILLINOIS  GLACIAL  LOBE. 

Upon  passing  eastward  from  Lake  County,  Indiana,  tlie  several  ridges 
become  combined  into  a  single  gi'eat  ridge  which  admits  of  but  little  sep- 
aration into  distinct  members  in  Porter  and  Laporte  counties,  Indiana, 
and  in  southern  Berrien  County,  Michigan.  In  northeastern  Ben'ien 
County  two  distinct  ridges  are  developed,  between  which  Pipestone  Creek 
flows  in  a  southwestward  course.  Farther  north  the  morainic  system  consists 
usually  of  a  main  ridge  on  the  eastern  or  outer  border  and  ridges  of  more 
or  less  definiteness  near  the  western  border,  between  which  there  are  lower 
tracts  with  gently  undulating  surface. 

The  ridges  just  discussed,  although  bulky,  are  in  places  less  impressive 
topographic  features  than  the  knolls  and  basins  which  dot  their  surfaces. 
They  usually  rise  gradually  from  border  to  crest,  and  their  dimensions  can 
be  appreciated  only  by  measurements  with  surveyor's  level  or  other  instru- 
ments. The  inner  border  in  Porter  and  Laporte  counties,  however,  usu- 
ally shows  an  abrupt  rise  of  100  feet  or  more  and  portions  of  the  inner 
border  in  Michigan  are  also  abrupt.  Such  is  the  case  in  the  vicinity  of  the 
St.  Joseph  River  in  central  Berrien  County,  and  at  frequent  intervals  from 
that  river  northward  to  the  Kalamazoo  River. 

Considerable  variation  in  surface  contour  is  displayed  in  each  of  the 
States  which  this  morainic  system  traverses.  In  the  Illinois  portion  the 
surface  is  usually  gently  undulating,  with  knolls  15  to  30  feet  in  height, 
separated  by  winding  sags  and  shallow  basins.  The  trend  of  these  knolls, 
when  on  the  crest  and  outer  part  of  tlie  morainic  system,  is  usually  about 
in  line  with  the  trend  of  the  ridges  whose  surface  they  occupy.  Near  the 
inner  border  of  'the  moraine,  however,  the  knolls  frequently  show  a  tend- 
ency to  elongation  at  right  ang-les  with  the  trend  of  the  morainic  system. 
The  crest  of  the  main  ridge  often  rises  abruptly  30  or  40  feet  above  the 
remainder  of  the  moraine  in  a  narrow  ridge  or  chain  of  knolls.  In  Lake 
Covmty,  Illinois,  there  are  numerous  small  lakes  occupying  the  basins 
among  the  morainic  Icnolls.  These  range  in  size  from  a  few  acres  up  to 
several  square  miles.  They  are  usually  shallow,  a  depth  of  50  feet  being 
seldom  attained,  wliile  tlie  majority  are  but  10  or  15  feet.  Among  the  lakes 
there  are  knolls  and  irregular  ridges  rising  10  to  50  feet  abo^"e  the  surtace. 
Some  of  the  lakes  are  bordered  by  extensive  marshes  on  one  or  more  sides, 
which  were  formerly  probably  covered  by  the  lakes,  for  it  is  not  rare  to 
find  beaches  a  few  feet  above  the  present  level  of  a  lake.     This  morainic 


THE  VALPARAISO  MORAmiO  SYSTEM.  347 

system,  as  indicated  below,  is  deeply  trenched  by  the  outlet  from  the  gla- 
cial Lake  Chicago,  which  discharged  from  the  southern  end  of  the  Lake 
Michigan  Basin  through  the  Des  Plaines  Valley. 

In  Lake  County,  Indiana,  the  contours  are  generally  subdued,  there 
being  few  knolls  more  than  20  or  30  feet  in  height.  Tributaries  of  the 
Kankakee  lead  soutliAvard  from  the  belt  on  the  north  border,  greatly  inter- 
rupting the  continuity  of  the  main  ridge.  Similarly  in  Will  County, 
Illinois,  the  main  ridge  is  trenched  by  the  headwater  tributaries  of  Hick- 
ory Creek  and  of  other  streams  flowing  southward  to  the  Des  Plaines  or 
Kankakee. 

In  Porter  and  Laporte  counties,  Indiana,  the  moraine  is  characterized 
by  sharper  knolls  than  in  Lake  County  and,  as  noted  above,  rises  with 
great  prominence  on  its  inner  border.  Lakelets  are  inclosed  among  the 
knolls  and  occur  also  on  the  outer  border  of  the  morainic  system  in  basins 
occupying  the  edge  of  the  overwash  gravel  apron. 

From  the  line  of  Indiana  and  Michigan  northward  the  morainic  system 
usually  presents  sharp  contours.  The  knolls  range  in  height  from  15  or  20 
feet  up  to  60  or  80  feet.  There  are  several  places  in  which  elevated  tracts 
several  square  miles  in  extent  rise  above  the  general  level  of  neighboring 
portions  of  the  moraine.  The  most  notable  instances  are  as  follows:  In 
Bainbiidge  Township,  Berrien  County;  in  central  Lawi-ence  Township, 
Van  Buren  County;  in  southern  Arlington  Township,  Van  Buren  County; 
in  northern  Bloomingdale  Township,  Van  Buren  County;  in  northwestern 
Trowbridge  and  northern  Cheshire  townships,  Allegan  County,  and  in  a 
tract  north  of  Allegan.  There  is  usually  ah  abrupt  border  on  two  or  more 
sides  of  these  tracts,  with  a  relief  of  60  to  100  feet  above  neighboring  por- 
tions of  the  moraine.  In  the  elevated  tract  north  of  Allegan  the  descent  is 
abrupt  both  on  the  north  and  east  sides,  and  in  Cheshire  Township  on  the 
north  and  west  sides.  The  morainic  tracts  in  northern  Bloomingdale  and 
southern  Cheshire  have  no  very  abrupt  borders.  The  tract  in  Arlington 
Township,  with  arm-like  projections  into  Hartford  Township,  has  an  abrupt 
border  on  all  sides.  The  tract  in  Bainbridge  Township  has  an  abrupt  border 
on  the  north  and  west  and  also  on  portions  of  the  east  and  south.  Were 
it  not  for  the  relief,  these  tracts  would  differ  but  little  from  the  neighboring 
lower  portions  of  the  morainic  system,  for  they  usually  present  only  small 
knolls  and  ridges  on  their  surfaces. 


348  THE  ILLINOIS  GLACIAL  LOBE. 

A  few  small  tracts  of  elevated  land  occur  along-  the  west  border  of  the 
morainic  system  in  southwestern  Michigan.  Such  tracts  in  Geneva,  Bangor, 
and  Watervliet  townships,  Van  Buren  County,  have  extreme  elevations  of 
50  to  75  feet  above  the  bordering  plains.  The  swells  rise  one  above  another 
in  passing  from  the  plains  to  the  highest  portions  of  these  tracts  and  the 
border  is  less  abrupt  than  in  the  larger  tracts  above  mentioned. 

There  are  a  few  points  where  very  sharp  knobs  were  noted  which  rise 
60  or  80  feet  above  the  border  portions  of  the  moraine.  These  occur  in  Wat- 
son Township, Allegan  County;  in  the  vicinity  of  Great  Bear  Lake  in  Van 
Bui-en  County;  on  the  south  side  of  Pawpaw  River,  near  Lawrence,  and  in 
several  places  along  the  eastern  border  of  the  morainic  system  in  Van  Buren 
and  Berrien  counties. 

In  the  Michigan  portion  of  this  morainic  system  marshes  are  a  verv 
common  feature,  there  being  usually  several  inclosed  among  the  morainic 
knolls  in  each  township.  Lakes  are  also  a  common  feature  from  northern 
Berrien  County  northward.  They  are  in  some  cases  two  or  three  square 
miles  in  area,  but  usually  occupy  less  than  a  square  mile.  So  far  as  known 
they  are  shallow  and,  like  those  of  the  Illinois  portion,  are  bordered  bv 
marshes  which  seem  to  have  been  formerly  covered  by  lake  water.  There 
are  also  lakes  along-  the  eastern  border  of  the  morainic  system  indenting  the 
gravel  plain.  These  are  conspicuous  in  northwestern  Cass  and  southern  Van 
Buren  counties. 

DETAILED   DESCRIPTION   OF   THE   MICHIGAN   PORTION. 

The  Michigan  portion  of  ihis  morainic  system  was  examined  in  more 
detail  than  the  remainder  of  the  system  because  its  surface  contours  are 
more  variable  and  because  it  had  received  very  little  attention  from  the 
earlier  students.  It  seems  appropriate,  therefore,  to  present  the  following 
detailed  discussion  of  the  topograph}-  of  this  portion.  The  area  first  con- 
sidered lies  in  central  Allegan  County,  and  the  discussion  is  then  extended 
to  points  farther  south. 

In  T.  2  N.  the  moraine  consists  of  two  well-defined  ridges  separated 
by  a  till  plain.  A  line  passing  across  the  morainic  system  from  west  to  east 
shows  the  following  features:  West  of  the  western  ridge  is  a  broad  plain 
covered  with  sand  called  the  "  Pine  Plain."  This  plain  stands  50  to  75  feet 
above  Lake  Michigan.      In  passing  eastward  from  it  an  abrupt  rise  is  made 


THE  YALPAEAISO  MOEAINIO  SYSTEM.  ^  3^9 

into  a  belt  of  billowy  land  standing  200  to  260  feet  above  the  lake,  the 
most  elevated  portion  being  at  the  east  in  central  Allegan  Township.  Here 
a  sudden  descent  is  made  to  a  narrow  till  plain  standing  150  to  160  feet 
above  Lake  Michigan,  east  of  which  an  abrupt  rise  takes  place  in  Watson 
Township  to  an  elevation  of  260  to  330  feet  above  the  lake,  or  840  to  910 
feet  above  tide.  This  rolling  belt  continues  to  the  west  part  of  Martin 
Township,  where  a  gravel  apron  borders  the  ixioraine,  having  an  elevation 
of  240  to  260  feet  above  Lake  Michigan,  or  820  to  840  feet  above  tide. 
The  very  elevated  portion  of  the  moi'aine  in  Watson  Township  appears  to 
be  doubled  upon  itself  in  a  peculiar  manner.  Its  western  part  is  bordered 
on  the  north,  west,  and  south  by  a  till  plain,  and  this  western  end  forms  a 
very  prominent  part  of  the  moraine,  having  knobs  80  feet  or  more  in  height 
above  the  bordering  basins  and  plains. 

Passing  now  to  T.  1  N.,  it  is  found  that  the  eastern  portion  of  the 
moraine  in  Watson  Township  continues  to  the  south  part  of  that  township 
and  there  turns  abruptly  to  the  west,  following  the  north  side  of  the  Kala- 
mazoo River  from  Otsego  to  Allegan,  along  the  south  border  of  the  till 
plain  referred  to  above.  At  AUeg'an  it  joins  a  rolling  sandy  tract  which 
lies  west  of  that  city,  and  the  combined  belt  takes  a  southwesterly  course, 
occupying  nearly  the  whole  of  Cheshire  Township.  The  north  and  west 
tiers  of  sections  are  partly  on  the  moraine  and  partly  on  the  sandy  plain 
which  borders  it  on  the  west.  The  morainic  system  is  here  narrowed  to 
the  width  of  a  single  township  and  has  the  Saginaw  moraines  combined 
with  its  eastern  border  and  the  Pine  Plains  bordering  it  on  the  west. 

Passing  to  T.  1  S.,  the  morainic  belt  is  found  to  spread  out  to  a  width 
of  nearly  15  miles.  Its  inner  border  takes  a  nearly  west  course  to  the 
vicinity  of  Grand  Junction.  It  then  passes  south  to  Breedsville,  lying  a 
short  distance  east  of  the  Chicago  and  West  Michigan  Railroad.  West  from 
this  railroad  in  Greneva  Township  are  isolated  tracts  with  undulatory  sur- 
faces surrounded  by  marshes,  swamps,  and  till  plains.  These  knolly  tracts 
extend  in  two  instances  north  across  the  base  line  into  Allegan  County,  so 
that  the  whole  district  south  of  the  "Pine  Plains"  in  both  T.  1  N.  and  T.  1 
S.  and  east  of  a  till  ridge  (Covert  Ridge)  which  borders  Lake  Michigan  in 
South  Haven  and  Casco  townships,  is  in  places  more  or  less  morainic  in 
topography,  but  the  main  morainic  belt  lies  east  of  the  Chicago  and 
Western  Michigan  Raihoad. 


350  THE  ILLINOIS  GLACIAL  LOBE. 

Passing  eastward  over  this  belt  there  is  an  ascent,  gradual  at  first,  over 
a  sandy  tract  in  Columbia  Township,  then  over  an  undiilatory  till  ridge  in 
Bloomingdale  Township,  which  changes  to  a  plain  in  the  central  part  of  the 
township ;  then  in  the  eastern  part  of  this  township  a  rapid  ascent  is  made 
to  the  high  portion  of  the  moraine  which  forms  the  eastern  border  of  the 
Lake  Michigan  di-ift.  This  border  is  at  Gobies,  on  the  line  of  the  Kalama- 
zoo and  South  Haven  Division  of  the  Michigan  Central  Railroad,  and  lies 
near  the  line  between  Bloomingdale  and  Pine  Grove  townships  throughout 
their  whole  length.  The  following  elevations  of  stations  along  the  railroad 
give  a  fair  idea  of  the  rise  of  the  moraine  toward  the  east  from  Grand 
Junction  to  Gobies: 

Elevations  of  stations  along  the  Kalamazoo  and  South  Haven  Division  of  the  Michigan 

Central  Railroad. 

Feet  above  tide. 

Grand  Junction 678 

Columbia 682 

Berlamont 700 

Bloomingdale 731 

Gobies 803 

At  least  60  feet  of  the  rise  between  Bloomingdale  and  Gobies  is  made 
within  1^  miles  of  the  latter  town.  There  is  scarcely  any  descent  to  the 
border  of  the  overwash  plain  or  apron  east  of  Gobies,  but  this  plain 
descends  20  feet  or  more  in  a  mile  toward  the  east  to  the  border  of  the 
Saginaw  moraine  near  Pine  Grove  Mills.  This  may  not  be  true  except 
along  the  railroad,  but  since  this  passes  through  a  wide  part  of  the  over- 
wash  plain  the  fact  is  significant. 

In  T.  2  S.  the  morainic  ridge  which  is  so  prominent  at  Gobies  grows 
feebler  for  3  miles  or  more  along  the  line  between  Almena  and  Waverly 
townships,  as  it  approaches  Pawpaw.  River,  rising  scarcely  50  feet  above 
this  stream  and  still  less  above  Brandywine  Creek,  which  lies  along  its 
western  border.  The  undulations  are  less  sharp  than  in  T.  1  S.  On  tlie 
south  side  of  Pawpaw  River  the  outer  border  of  the  moraine  takes  a  nearly 
east  to  west  course  for  5  or  6  miles.  Its  prominent  portion  lies  mainly  in 
T.  3  S.,  barely  reaching  into  Waverly  Township.  There  is  a  gap  2  or  3 
miles  long  just  nortli  of  the  village  of  Pawpaw  whei'e  no  moraine  is  devel- 
oped, but  the  swamps  which  follow  Pawpaw  River  are  bordered  on  the  east 
by  the  overwash  ajiron  of  a  moraine  of  the  Saginaw  series.  West  of 
Pawpaw  the  moraine  assumes  a  strength  of  development  even  greater  than 


THE  VALPAKAISO  MOEAINIC  SYSTEM.  351 

that  near  Gobies,  rising  nearly  150  feet  above  the  Pawpaw  River  swamps, 
4  to  6  miles  west  of  the  village  of  Pawpaw,  and  haA'ing  a  breadth  from  the 
swamp  on  the  north  to  an  overwash  apron  on  the  south  of  only  IJ  to  2 
miles. 

Waverly  Township  is  much  of  it  comparatively  level  and  swampy,  but 
the  topography  of  the  northwestern  part  is  morainic.  This  belt  connects 
on  the  north  with  the  morainic  belt  which  passes  through  western  Bloom- 
ing'dale  and  eastern  Columbia  townships. 

In  northeastern  Arlington  Township,  which  adjoins  Waverly  on  the 
west,  is  a  swamp,  which  comprises  about  one-third  of  the  township.  It  is 
bordered  on  the  north  and  east  by  the  billowy  belt  in  Columbia,  Blooming- 
ton,  and  Waverly  townships,  and  on  the  southeast  by  an  elevated  billowy 
tract  in  Arlington  Township,  which  constitutes  the  most  prominent  portion 
of  the  moraine  in  this  tier  of  townships.  This  prominent  morainic  belt 
extends  southwest  through  southeastern  Bangor  Township  to  the  Pawpaw 
River,  near  Hartford.  Its  south  border  lies  along  the  river  for  a  distance 
of  nearly  10  miles  from  the  east  line  of  Arlington  Township  to  the  village 
of  Hartford.  The  river  is  also  bordered  on  the  south  by  a  similar  promi- 
nent belt,  which  is  described  in  connection  with  the  next  tier  of  townships. 

Bangor  Township,  which  lies  west  of  Arlington,  has  a  series  of  swamps, 
till  plains,  and  island-like  billowy  tracts,  the  swamps  and  till  plains  together 
occupying  more  than  half  of  the  surface. 

The  moraine  in  this  tier  of  townships,  therefore,  has  a  width  of  about 
18  miles,  and  is  highest  in  the  middle  portion,  while  in  the  tier  of  townships 
on  the  north  it  is  nearly  as  wide,  but  its  most  prominent  part  is  the  eastern 
border.  The  curve  in  the  outer  border  of  the  moraine  makes  the  prominent 
morainic  belt  south  of  Waverly  Township  the  correlative  of  the  morainic 
belt  near  Grobles,  in  T.  1  S.,  and  this  belt  is  more  prominent  than  the  middle 
portion  in  Arhngton  Township.  The  rule,  therefore,  still  holds  good — if 
we  overlook  the  break  north  of  Pawpaw — that  the  eastern  or  outer  border 
is  the  highest  part  of  the  moraine,  and  this  rule  continues  to  apply  as  far 
south  as  the  Indiana  line. 

In  T.  3  S.,  at  the  western  border  of  the  morainic  belt  in  Watervliet 
Township,  there  is  immediately  east  of  the  till  ridge  which  cuts  across  its 
northwest  corner  a  series  of  till  plains  interspersed  with  island-like  billowy 
tracts  and  dotted  with  lakelets,  differing  from  Bangor  Township  in  having 


352  THE  ILLINOIS  GLACIAL  LOBE. 

lakelets  instead  of  swamps.  In  Hartford  Township,  which  borders  Water- 
vliet  on  the  east,  there  are  till  plains,  sand  plains,  and  island-like  billowy 
belts  over  about  two-thirds  of  the  township,  but  the  two  tiers  of  sections  in 
the  east  contain  an  elevated  part  of  the  moraine.  Lawrence  Township, 
which  lies  east  of  Hartford,  has  a  prominent  part  of  the  moraine  occupying' 
nearly  the  whole  of  its  surface,  there  being  but  two  notable  exceptions,  the 
valley  of  the  Pawpaw  River,  which  passes  from  east  to  west  through  the 
northern  part  of  the  township,  and  the  overwash  apron  which  borders 
the  moraine  in  the  east  part  of  the  township.  The  overwash  apron  swings 
around  the  moraine  across  Hamilton  Township,  which  lies  south  of  Law- 
rence, and  thus  in  the  north  part  of  T.  4  S.,  as  well  as  in  T.  3  S.,  the 
morainic  border  has  for  several  miles  a  neai'ly  east  to  west  trend.  Contin- 
uing its  course  in  T.  4  S.,  we  find  the  morainic  border  turning  southwest 
near  Keeler  Center  and  entering  Cass  County  from  the  southwest  comer  of 
Keeler  Township,  cutting  off  a  section  or  more  of  this  county  in  its  extreme 
northwest  corner,  then  entering  the  eastern  part  of  Pipestone  Township, 
Berrien  County. 

Passing  westward  through  T.  4  S.,  the  moraine  becomes  prominent  in 
western  Keeler,  Bainbridge,  and  eastern  Benton  townships.  It  divides  in 
the  southern  part  of  Bainbridge  township  at  Pipestone  Lake,  and  from  this 
point  south,  in  Pipestone  Township),  incloses  a  low  belt  along  the  Pipestone 
River  in  which  flowing  wells  have  been  obtained.  The  eastern  limb  passes 
southwest  through  the  southeastern  part  of  Pipestone  Township,  and  the 
western  limb  passes  southwest  across  the  northwest  corner  of  Pipestone 
Township  into  Sodus  Township  and  occupies  the  eastern  portion  of  this 
township  to  the  St.  Joseph  River. 

From  Benton  Township  southward  nearly  to  the  Indiana  line  the  west- 
ern or  imier  border  is  more  sharply  defined  than  it  is  north  of  this  township. 
It  rises  abruptly  100  feet  or  more  above  the  swamps  or  till  plains  which  lie 
along  the  foot  of  the  range  of  sandy  hills  which  form  its  front.  For  a  few 
miles  in  southern  Berrien  County,  Michigan,  this  border  is  not  abrupt,  but 
upon  passing  into  Laporte  County,  Indiana,  it  again  becomes  abrupt  and 
continues  so  across  Laporte  and  Porter  counties.  Along  the  eastern  or  outer 
border  in  Berrien  County  lakes  are  numerous.  They  are  usually  in  deep 
depressions  50  feet  or  more  below  bordering  portions  of  the  moraine.  There 
are  also  lakes  on  the  gravel  plain  outside  the  moraine,  occupying  basins 


THE  VALPARAISO  MOEAI^flC  SYSTEM.  353 

sunk  30  to  40  feet  or  more  below  the  general  level  of  tlie  plain.  The  St. 
Joseph  River  is  bordered  by  broad  gravelly  teiTaces  2  miles  or  more  in 
width  from  the  inner  border  of  the  moraine  southward  a  short  distance 
beyond  Berrien  Springs.  From  this  point  up  to  Buchanan  the  moraine  bor- 
ders the  valley  closely  on  each  side.  Above  Buchanan  the  river  is  again 
bordered  by  gravel  terraces  which  are  cut  in  the  gravel- plain  that  was 
formed  on  the  outer  border  of  the  moraine. 

THICKNESS   OF   THE   DRIFT. 

Situated  as  the  Valparaiso  system  is,  in  a  district  over  which  there 
have  probably  been  several  successive  ice  advances  with  intervening 
recessions,  the  drift  can  scarcely  be  supposed  to  belong  solely  to  the 
advance  which  formed  this  morainic  system.  It  is  known  that  remnants 
of  the  sheets  of  the  lUinoian  and  lowan  drift  are  present  in  northeastern 
Illinois  and  northwestern  Indiana.  There  is  also  present  a  considerable 
amount  of  drift  of  the  early  Wisconsin  series.  The  early  Wisconsin  drift  is 
so  similar  to  that  of  the  Valparaiso  drift  sheet  that  it  is  doubtful  if  it  can  be 
readily  distinguished  or  separated  from  it.  There  does  not  appear  to  be  a 
well-deiined  soil  horizon  at  the  base  of  the  Valparaiso  sheet  to  mark  the  line 
of  junction,  such  as  occurs  under  wide  ai-eas  at  the  base  of  the  early  Wiscon- 
sin drift.  The  thickness  of  the  Valparaiso  di'ift  sheet  can  perhaj)s  be  best 
estimated  by  the  relief,  for  it  can  scarcely  be  assumed  to  exceed  greatly 
the  measure  of  the  outer-border  relief  of  the  moraine,  except  in  jDlaces 
where  there  is  a  great  gravel  filling  on  that  border.  The  gravel  filling  is  of 
little  consequence  on  the  outer  border  of  the  Valparaiso  morainic  system  in 
Illinois  and  in  Lake  and  Porter  counties,  Indiana.  Farther  east  and  north 
it  is  of  considerable  depth.  The  relief  in  the  Illinois  portion  is  estimated  to 
average  about  65  feet.  The  average  thickness  of  the  Valparaiso  sheet  is 
probably  somewhat  less  than  the  relief,  since  the  sheet  is  markedly  thinner 
on  the  borders  of  the  morainic  system  than  along  its  main  crest. 

In  southwestern  Michigan  it  is  difficult  to  determine  whether  the  early 
Wisconsin  sheets  are  present  in  large  amount.  A  fresh  diift  of  great  depth 
is  found  along  the  line  of  the  morainic  system  and  westward  from  it  to  the 
borders  of  Lake  Michigan.  In  all  probability  the  thickness  of  the  Val- 
paraiso sheet  is  as  great  in  southwestern  Michigan  as  in  northeastern  Illinois 
and  northwestern  Indiana,  and  it  may  be  even  greater. 
MON  xxxviii 23 


354 


THE  ILLINOIS  GLACIAL  LOBE. 


The  combined  thickness  of  the  several  sheets  of  drift  has  been  deter- 
mined at  various  points  along  the  line  of  this  morainic  system,  while  at 
other  points  wells  have  been  sunk  to  great  depth  without  reaching  the 
bottom  of  the  drift.  The  rock  surface  beneath  the  di'ift  appears  to  be  quite 
uneven,  there  being  a  known  range  from  about  100  feet  above  the  level  of 
Lake  Michigan  to  more  than  100  feet  below  the  surface  of  the  lake.  The 
following  list  of  deep  borings  sets  forth  the  A^ariations  in  the  thickness  of  the 
drift  and  the  elevation  of  the  rock  "surface : 


List  ofboriugs  showing  thickness  of  drift  along  the  Valjiaraiso  morainic  system. 


At  I  vanhoe,  Illinois,  on  crest 

Near  Lake  Zurich,  on  crest 

At  Lake  Zurich,  20  to  30  feet  below  crest 

Haines vi  lie,  near  crest 

G  ilmer,  near  crest 

Crest  east  of  Wauconda 

Crest  south  of  Barringtou 

Barriugton,  40  to  45  feet  below  crest 

East  of  Elgin,  near  crest 

Palatine  and  vicinity 

Near  Schanmberg,  along  crest 

Arlington  Heights,  about  150  feet  below  crest 

North  of  Arlington  Heights,  20  to  30  feet  above  station  . 

Near  Spauldiug,  about  50  feet  below  crest 

Bartlett,  10  to  20  feet  below  iTest 

Ontarioville,  near  crest 

Roselle,  about  50  feet  below  crest 

Crest  south  of  Bloomiugdale 

Itasca 

Bcuseu  ville 

Elmhurst 

Turner  .Junction 

Crest  east  of  Naperville 

Downer's  Grove 

Crest  cast  <if  1  )owiier  s  Grove 

Neiir  Clarendon  Hills , 

Crest  northwest  of  Lemont 

Cre.st  of  moraine  east  of  Lockport 

Near  Spencer 


Thickness  of 
drift. 


Feet. 
290 
a267+ 
240+ 
287+ 
213+ 
230+ 
315+ 
254 
220-240 
100-170+ 
190+ 
128 
190 
120 
100+ 
140+ 
100+ 
162 
72+ 
97 
98 
116 
115+ 
113+ 
159 
160+ 
150 
115+ 
81 


Klevation 
of  well 
mouth. 


Feet. 
800 
900 
880 
880 
820 
850 
850 
818 
850 
750 
825 
700 
725 
770 
800 
815 
770 
800 
692 
677 
688 
765 
740 
720 
750 
755 
740 
725 
710 


Elevation 
of  rock 
surface. 


Feet. 
510 

(?) 
(?) 
(?) 
(?) 
(?) 
(?) 
564 
610 
650 

(?) 
572 
535 
650 

(?) 

(?) 
(?) 
638 

(?) 
580 
590 
649 

(?) 

(?) 
591 

(?) 
590 

(?) 
629 


a  Whore  the  +  sign  is  alBxed  the  rook  Is  not  reached. 


THE  VALPARAISO  MOEAINIC  SYSTEM.  855 

Lint  of  borings  sliowing  thickness  of  drift  along  the  Valparaiso  morainic  system — Cont'd. 


Thickness  of 
drift. 


Elevation 
of  well 
mouth. 


Elevation 
of  rock 
surface. 


Feel. 


Crest  uear  Frankfort , ■ 

Moiiee,oiicrest - 

Crest  near  Goodenow 

Beecher 

Sec.  11,  T.  34,  R.  XIV  E 

Chicago  Heights 

Crown  Point,  Iiul 

Hebron,  lud 

Three  miles  south  of  Wlieeler,  lud 

Two  miles  north  of  Wheeler,  lud 

Valparaiso,  Ind 

Woodville,  lud 

Jackson  Center,  Ind 

Near  Coburg,  Ind 

Laporte,  lud 

■  Berrien  County,  Mich.,  sec.  14,  Baiubridge  Township.. 

Berrien  County,  Mich.,  sec.  12,  Baiubridge  Township.. 

Berrien  County,  Mich.,  sec.  2,  Pipestone  Township  -. .. 

Van  Buren  County,  Mich.,  sec.  5,  Hamilton  Township. 

Van  Buren  County,  Mich.,  sec.  1,  Lawrence  Township. 

Van  Buren  County,  Mich.,  sec.  17,  Lawrence  Township 

Van  Buren  County,  Mich.,  sec.  17,  Bangor  Township.. 

Van  Buren  County,  Mich.,  sec.  11,  Hartford  Township 

Vail  Buren  County,  Mich.,  sec.  21,  Arlington  Township 

Van  Buren  County,  Mich.,  sec.  23,  Arlington  Township 

Van  Buren  County,  Mich.,  near  Gobies 

Van  Buren  County,  Mich.,  near  Bloomingdale 

'    Van  Buren  County,  Mich.,  near  Columbia 

Van  Buren  County,  Mich.,  sec.  2.5,  Columbia  Township 

Allegan  County,  Mich.,  Lee  station 

Allegan  County,  Mich.,  sec.  19,  Cheshire  Township.. .. 

Allegan  County,  Mich.,  sec.  6,  Martin  Township 

I     Allegan  County,  Mich.,  sec.  20,  Martin  Township 

Allegan  County,  Mich.,  sec.  9,  Watson  Township 

One  mile  south  of  .iUegan 

Allegan  waterworks , 

East  of  Allegan 

Ohio  Corners 

Near  Ohio  Corners 


135+; 

180+; 

112+1 
106+ 
106+ 

30 
176 
108 
219+ 
200+ 
125- 
158+ 
167+ 
148+ 
295 
117+ 
125+ 
155+ 
110+ 
125+ 
230+ 
104+' 
160+ 
125+ 
162+ 
109+ 
110+ 
178+ 
125+ 
120+ 
108+ 
112+ 
150 
150  + 
180+ 
180+ 
216+ 

95 
165+ 


Feet. 
780 
804 
780 
720 
720 
690 
736 
713 
700 
660 
715 
687 
825 
800 
810 
750 
750 
700 
800 
800 
775 
700 
730 
775 
775 
800 
750 
685 
750 
648 
750 
820 
820 
860 
710 
650 
710 
750 
750 


Fee'i 


660 
560 
605 


590 


655 

(?) 


356  THE  ILLINOIS  GLACIAL  LOBE. 


STETJCTUBB   OF   THE   DRIFT. 


The  drift  of  the  Valparaiso  sheet  is  found  to  show  interesting-  changes 
in  structure  when  followed  around  the  head  of  Lake  Michigan.  In  the 
Illinois  portion  it  consists  mainly  of  a  soft  blue  till,  similar  to  that  forming 
the  bulk  of  the  moraines  in  the  early  Wisconsin  series  in  that  State.  Upon 
passing  eastward  into  Indiana  till  predominates  over  sand  and  gravel  as  far 
east  as  the  meridian  of  Valparaiso.  From  this  line  northeastward  there  is 
a  decided  change  in  constitution,  and  sand  and  gravel  predominate  over  till. 
The  prominent  portions  of  the  morainic  system  appear  to  contain  a  larger 
proportion  of  sand  and  gravel  than  the  lower  portions.  This  is  trixe  not 
only  of  Porter  and  Laporte  counties,  Indiana,  but  of  Berrien,  Van  Bureu 
and  Allegan  counties,  Michigan.  It  is  not  rare  to  find  well  sections  in  these 
prominent  portions  of  the  morainic  system  which  penetrate  nothing  but 
sand  and  gravel  in  a  depth  of  100  feet  or  more.  Till,  however,  is  usually 
present  in  small  amount  on  these  elevated  tracts.  In  Lake  and  Porter 
counties,  Indiana,  the  till  has  considerable  depth  on  the  north  or  inner 
border  of  the  morainic  system,  but  is  underlain  at  slight  depth  by  sand  and 
gravel  on  the  southern  border  of  this  system,  thus  forming  a  phase  inter- 
mediate between  the  gravelly,  sandy  portion  to  the  east  and  the  till  portion 
to  the  west. 

The  cause  for  the  marked  difference  in  constitution  displayed  by  this 
morainic  system  can  as  yet  only  be  conjectured.  The  writer's  attention  was 
called  by  Mr.  F.  B.  Taylor  to  the  coincidence  of  the  gravelly  and  sandy 
portion  of  the  morainic  system  with  the  extent  of  prominent  dunes  along 
the  shore  of  the  lake,  and  the  suggestion  was  made  that  the  great  abun- 
dance of  sand  in  this  portion  of  the  moraine  may  be  due  to  the  incorpora- 
tion of  dune  material  which  had  been  blown  into  that  region  during  an 
interglacial  interval.  Some  doubt  concerning  this  view  is  raised  by  the 
absence  of  sandy  material  in  the  other  moraines  formed  on  the  southeast 
border  of  Lake  Michigan.  Tliis,  however,  may  not  be  a  fatal  objection, 
since  the  invasion  which  formed  the  Valparaiso  moraine  may  have  gathered 
up  the  entire  deposit  of  dune  material  and  may  have  been  followed  so  closely 
by  the  deposition  of  the  later  moraines  that  no  opportunity  for  the  forma- 
tion of  dunes  was  afforded.  In  the  writer's  opinion  a  cause  for  the  sandy 
and  gravelly  constitution  may  be  found  in  the  relation  of  the  Lake  Michi- 


THE  VALPAEAISO  MOEAINIO  SYSTEM.  357 

gaii  and  Saginaw  lobes,  since  the  sandy  and  gravelly  phase  is  confined 
nearly  to  the  portion  of  the  Lake  Michigan  belt  closely  associated  with  the 
Saginaw  lobe.  These  causes  are  not  antagonistic  and  may  supplement  each 
other;  j)ossibly  other  causes  will  be  found  to  ha-se  been  effective  in  produc- 
ino-  the  lara-e  amotmt  of  sand  and  g-ravel. 

The  surface  of  the  moraine  is  strewn  with  a  moderate  number  of 
bowlders.  They  are  mainly  crystalline  rocks  of  Canadian  derivation.  The 
great  majority  fall  below  3  feet  in  diameter.  There  are,  however,  occasional 
immense  bowdders  of  Corniferous  limestone  and  of  sandstone  found  on  the 
Michigan  jjortion  of  the  morainic  system.  In  western  Bangor  Township, 
Van  Buren  County,  sandstone  bowdders  are  scattered  over  a  tract  about  a 
mile  and  a  half  from  noi'th  to  south  and  scarcely  half  a  mile  in  width.  They 
are  most  abundant  in  sees.  16  and  17,  on  a  prominent  knoll  which  is  situ- 
ated on  the  border  of  the  section.  One  bowlder  on  this  knoll  was  made 
use  of  to  build  a  large  stone  house  in  Hartford,  Michigan.  Two  other  large 
bowlders  still  remaui  on  the  knoll,  the  larger  one  24  by  24  by  21  by  21  feet 
on  the  sides;  the  other  24  by  30  by  18  by  15  feet.  They  each  stand  6  or  8 
feet  above  the  surface  and  extend  an  unknown  distance  benaath.  The 
owner  of  the  farm  on  which  they  are  situated  states  that  he  dug  down  6 
feet  b}'  the  side  of  one  of  them  and  did  not  reach  the  bottom.  Similar 
bowlders  are  found  in  Bloomingdale  Township,  scattered  over  a  belt  nearly 
3  miles  in  length  and  scarcely  100  rods  in  width.  The  north  end  is  near 
the  Base  Line  in  sec.  4,  and  the  south  end  in  sec.  17,  about  a  half  mile 
west  of  Bloomingdale  station.  They  abound  on  the  most  prominent  points 
along  this  line,  but  are  seldom  foimd  on  the  low  land  between  the  knolls. 
They  are  embedded  in  the  ground  at  various  angles,  some  standing  nearly . 
on  edge.  The  largest  ones  measure  15  or  20  feet  in  diameter  and  stand  6 
or  8  feet  above  the  surface.  It  is  reported  that  similar  large  sandstone 
bowlders  occur  in  sec.  33,  Bloomingdale  Township,  but  these  were  not  visited 
by  the  writer.  These  sandstones  are  mainly  of  red  or  pink  color,  but  a 
few  specimens  are  brown.  A  large  limestone  block  was  noted  in  sec.  11, 
Hartford  Township,  Van  Bui-en  County.  It  had  been  uncovered  to  the 
extent  of  about  a  rod  square,  and  had  been  quarried  to  a  depth  of  about  3 
feet,  yet  neither  its  lateral  limits  nor  its  bottom  had  been  reached.  A 
bowlder  of  the  same  kind  of  limestone  occurs  on  the  base  line  between 
Bloomingdale  and  Cheshire  townships,  less  than  a  mile  west  of  the  north 


358  THE  ILLINOIS  GLACIAL  LOBE. 

end  of  the  sandstone  belt  above  noted.  This  is  about  5  feet  square  and  18 
to  20  inches  in  thickness.  Probably  other  large  bowlders  occur  in  this 
region,  for  no  exhaustive  search  was  made.  The  sandstone  bowlders  appear 
to  be  of  northern  derivation,  though  the  exact  locality  and  geological  horizon 
of  the  beds  from  which  they  came  have  not  been  determined.  One  of  the 
limestone  bowlders  in  Van  Buren  County,  examined  hj  Dr.  Alexander 
Winchell,  is  referred  by  him  to  the  Corniferous.  Possibly  the  outcrop  of 
this  rock  is  to  the  north  beneath  Lake  Michigan.  They  are  now  at  an 
elevation  of  150  feet  above  the  level  of  the  lake  in  a  district  where  the 
drift  deposits  are  shown  by  the  wells  to  be  very  thick. 

In  this  connection  it  may  be  remarked  that  one  of  these  limestone 
bowlders  in  Van  Buren  County  has  been  refen-ed  to  by  Winchell  in  evi- 
dence of  a  northward  transportation  of  drift.^  This  bowlder  is  mentioned 
in  connection  with  others  noted  in  Hillsdale,  Jackson,  and  Lenawee  coun- 
ties, Michigan,  and  all  are  supposed  to  have  been  transported  northwestward 
by  an  ice  movement  from  the  border  of  Lake  Erie.  Winchell  was  probably 
correct  in  his  interpretation  of  northward  transportation  into  the  counties  in 
southeastern  Michigan,  for  the  Lake  Erie  glacier  would  very  naturallv  liaA-e 
given  limestones  on  the  north  border  of  the  lake  a  northward  transporta- 
tion, but  the  Erie  ice  movement  can  scarcely  be  supposed  to  have  extended 
to  Van  Buren  County. 

It  may  naturally  be  inferred  that  strong  wells  are  difficult  to  obtain  in 
the  portion  of  this  morainic  belt  where  till  greatly  predominates  over  sand 
and  gravel.  It  is  found,  however,  that,  with  the  exception  of  a  small  section 
embracing  southern  Lake,  northwestern  Cook,  and  northern  and  eastern 
Dupage  counties,  wells  suitable  for  supplying  stock  and  dairy  farms  may 
be  obtained  at  convenient  depths.  In  Will  County  wells  seldom  reach  a 
depth  of  100  feet  because  of  abundance  of  water-bearing  sand  and  gravel 
at  less  depth.  The  same  is  true  of  Lake  and  Porter  counties,  Indiana,  and 
of  much  of  Cook  and  Lake  counties,  Illinois.  In  the  district  where  wells 
are  difficult  to  obtain,  it  is  often  necessary  to  sink  to  a  depth  of  150  feet  or 
more.  This  carries  the  wells  into  the  older  drift  sheets  beneath  the  Wis- 
consin drift.  Well  sections  obtained  in  the  Illinois  portion  of  this  morainic 
system  are  presented  in  the  discussion  of  wells  below;  those  in  the  Indiana 

'Am.  Jour.  Soi.,  2d  ser.,  Vol.  XL,  1865,  p.  331. 


THE  VALPARAISO  MORAINIC  SYSTEM.  359 

portion  are  discussed  in  another  report;^  the  wells  of  the  Michigan  portion 
are  taken  up  in  some  detail  at  this  point.  The  discussion  begins  with 
Allegan  County,  at  the  north  end  of  the  district  examined,  and  proceeds  to 
consider  areas  lying  southward. 

A  well  on  the  farm  of  G.  H.  Hill,  2  miles  west  of  Allegan,  on  the 
elevated  sandy  land  south  of  the  Kalamazoo  River,  penetrates  sand  and 
gravel  slightly  cemented  near  bottom,  63  feet,  and  terminates  at  65  feet  in 
a  sticky  blue  clay,  apparently  pebbleless.  Another  well  on  the  same  farm 
penetrated  50  feet  of  sand  and  gravel  and  entered  a  similar  sticky  blue  clay 
4  feet.  This  clay  is  perhaps  a  silt  deposited  in  advance  of  the  ice  invasion 
by  which  the  morainic  system  was  formed. 

Immediately  north  of  these  wells  in  the  Kalamazoo  River  Valley,  wells 

are  20  to   22  feet  in  depth  and   are  mainly  in  a  loose  sand  with  some 

cemented  gravel.     In  some  wells  there  is  near  the  bottom  an  oily,  stickj^, 

blue  clay,  8  feet  or  more  in  depth,  and  occasionally  a  yellowish  brown  till 

is  encountered.     Three  prospect  borings  for  oil  at  Allegan  penetrate  about 

240  feet  of  drift,  of  which  the  upper  120  feet  is  sand  and  clay,  and  the  lower 

120  feet  mainly  gravel.'     In  the  Kalamazoo  Valley,  at  the  waterworks  in 

Allegan,  a  well  has  been  sunk  to  a  depth  of  180  feet  in  partially  cemented 

gravel  with  a  very  little  till.     The  bluffs  of  the  river  at  Allegan  are  about 

60  feet  in  height  and  present  the  following  section  in  the  south  part  of  the 

city: 

Section  at  Allegan,  Michigan. 

Feet, 

Loose  gravelly  sand 20-25 

Cemented  gravel 20-22 

Loose  sandy  gravel 20 

If  this  be  added  to  the  180  feet  of  assorted  material  penetrated  in  the 
waterworks  well  it  gives  a  section  240  feet  in  depth,  nearly  all  of  which  is 
assorted  material,  fully  two-thirds  being  cemented  gravel.  On  the  north 
side  of  the  river,  about  a  quarter  of  a  mile  west  of  the  railway  station,  a  blue 
silt  is  exposed  up  to  within  20  feet  of  the  top  of  bluff.  To  show  equally  great 
contrast  in  structure  within  a  short  range  another  well  section  is  cited.  It 
is  on  the  west  bluff"  of  the  Kalamazoo  River,  about  a  mile  south  of  Allegan 

'  Wells  of  northern  Indiana,  by  Frank  Leverett:  Water-Supply  and  Irrigation  Papers,  No.  21, 
U.  S.  Geol.  Survey. 

■^See  Geological  Survey  of  Michigan,  Vol.  V,  1895,  part  2,  p.  45;  also  Pis.  XXX-XXXII. 


360  THE  ILLINOIS  GLACIAL  LOBE. 

ou  the  farm  of  A.  Stedgmau.  This  penetrates  a  few  feet  of  yellow  till,  and 
is  then  in  a  blue-gray  till  to  the  depth  of  100  feet,  below  which  is  a  white 
quicksand  about  80  feet  in  depth.  Water  was  obtained  in  a  gravel  bed  at 
the  bottom  of  the  quicksand. 

A  well  on  the  moraine  north  of  Allegan,  sec.  11,  Pine  Plains  Township, 
penetrates  the  following  beds: 

Section  on  moraine  north  of  Allegan,  Michigan. 

Feet. 

Yellow  clay  loam 8-10 

Blue-gray  till 10 

Cemented  gravel 58-60 

Depth  78 

In  some  cases  wells  on  the  moraine  in  this  Aacinity  jjenetrate  till  35  to 
40  feet.  It  is  more  or  less  oxidized,  and,  as  a  rule,  is  A^erv  pebbly.  Below 
the  till  there  is  usually  cemented  gravel.  In  the  low  belt  between  the  two 
till  ridges  north  of  Allegan  along  the  line  of  the  Lake  Shore  and  Michigan 
Southern  Railroad  wells  penetrate  a  slight  depth  of  till  of  a  yellowish  blue 
color,  somewhat  pebbl}',  below  which  is  a  blue  quicksand. 

Mr.  H.  W.  Austin,  an  experienced  well  borer  residing  at  Allegan,  finds 
that  where  there  is  till  of  a  blue  color  much  cemented  g-ravel  is  seldom 
encountered,  but  there  is  a  loose  gravel  or  sand,  sometimes  a  quicksand, 
beneath  the  till.  When  cemented  gravel  of  considerable  depth  is  overlain 
by  till,  the  till  is  usually  more  or  less  oxidized,  even  to  a  depth  of  30  or  40 
feet. 

East  of  Allegan  is  a  till  lilain  in  which  a  deep  boring  having  the  fol- 
lowing section  was  made  on  the  farm  of  Chauucey  Palmer.  It  was  aban- 
doned without  obtaining  water  or  reaching  the  bottom  of  the  till: 

Section  in  till  pJain  east  of  Allegan. 

Feet. 

Yellow  till 4 

Blue  till,  compact,  with  few  pebbles 168 

Gravelly  clay 6 

Blue  till 38 

Depth 216 

There  are  shallow  flowing  wells  ou  the  till  plain  east  of  Allegan.  One 
in  sec.  21,  Watson  Townsliip,  on  the  farm  of  A.  Alexander,  is  20  feet  in 
depth  and  penetrates  slightly  oxidized  blue  till,  obtaining  water  in  gravel. 
One  in  sec.  20,  Watson  Township  (T.  2  X.,  R.  12  W.),  on  the  farm  of  S. 


THE  VALPARAISO  MOEAINIC  SYSTEM.  361 

Van  Duseu,  40  feet  in  depth,  penetrates  a  sticky  blue  clay  almost  pel^ble- 
less  and  obtains  water  from  a  gravel.  There  are  three  flowing-  wells  in  sec. 
34,  Watson  Township,  none  of  them  exceeding  50  feet  in  dejDth,  of  which 
the  major  part  of  the  section  was  gray  till.  A  flowing  well  near  the  south 
line  of  Watson  Township,  1 J  miles  east  of  Abronia,  on  the  farm  of  Martin 
Hewer,  penetrates  a  blue-gray  till  87  feet  and  obtains  its  flow  from  a  bed 
of  sand.  The  source  of  supply  for  these  wells  is  probably  in  the  neigh- 
boring high  parts  of  the  Valparaiso  morainic  system. 

On  a  very  elevated  portion  of  the  moraine  in  sec.  9  of  the  same  town- 
ship (T.  2  N.,  R.  12  W.),  where  the  elevation  is  about  150  feet  above  the 
boring  at  Mr.  Palmer's,  a  well  penetrated  dry  sand  and  g-ravel  to  a  dejoth  of 
125  feet,  and  beneath  this  25  feet  of  cemented  gravel  interbedded  with 
reddish  clayey  gravel.  On  this  elevated  tract  several  wells  80  to  120  feet 
in  depth  are  largely  in  assorted  material.  They  contain  thin  beds  of  bluish 
clay  alternating  with  thick  beds  of  sand  and  gravel. 

North  of  this  elevated  tract,  on  the  till  plain  which  sweeps  around  its 
western  end,  there  are  several  flowing  wells.  They  are  in  the  southern  part 
of  Hopkins  and  western  part  of  Wayland  townships  (T.  3  N.,  R.  12  W.  and 
T.  3  N,  R.  11  W.).  Their  surface  elevation  is  about  100  feet  lower  than  the 
general  elevation  of  the  bordering  moraine,  and  150  to  175  feet  lower  than 
the  highest  points.  They  range  in  depth  from  40  to  165  feet.  The)'  are 
mainly  through  blue  till,  beneath  which  is  a  hard  gray  clay. 

A  well  near  Ohio  Corners,  about  2  miles  north  of  Hopkins,  penetrates 
the  following  beds: 

Section  in  well  near  Ohio  Corners,  Michigan. 

I-eet. 

1.  Water-bearing  gravel , 24 

2.  Blue-gray  till 66 

3.  Gravel  and  water 5 

4.  Limestone  (?) 40 

5.  Blue  sandy  clay  (shale?) Ill 

.     Depth  246 

At  the  bottom  of  this  clay  solid  rock  about  a  foot  in  thickness  was 
found  and  below  this  salt  water  was  struck.  If  no  mistake  was  made  by 
the  well  borer  in  identifying  "No.  4"  as  limestone,  the  rock  here  attains  an 
elevation  of  at  least  650  feet  above  tide,  an  unusual  elevation  for  this  latitude 
so  near  the  east  shore  of  Lake  Michigan.     Perhaps  "No.  5"  is  a  shale. 


362  THE  ILLINOIS  GLACIAL  LOBE. 

On  the  overwash  gravel  plain  in  western  Maitin  Townsliip,  Allegan 
County  (T.  2  N.,  R.  11  W.),  a  well  in  the  northern  part  of  sec.  20  pene- 
ti-ates  sand  and  gravel  50  feet;  beneath  this  a  hard  bine  bowlder  clay  100 
feet.  The  well  was  abandoned  without  reaching  the  bottom  of  the  clay. 
A  well  in  the  southern  part  of  sec.  6  peneti'ates  the  following  beds: 

Section  in  icell  in  Martin  Township,  Allegan  County,  Michigan. 

Feet. 

Loamy  clay  anil  gravel 5-6 

Cemented  gravel 15 

Blue-gray  till 1:^-15 

Gravel 6-8 

Quicksand -- 6-8 

Gravelly  clay,  slightly  oxidized 30 

Blue-gray  till 30 

Gravel 1 

Depth '. 112 

Many  wells  on  this  overwash  plain  -40  feet  in  depth  are  entirely  in  sand 
and  gravel,  after  passing  through  the  soil  and  a  slightly  cemented  gravelly 
and  loamy  clay  2  to  4  feet  in  depth. 

In  an  excavation  made  by  the  Grrand  Rapids  and  Indiana  Railroad  in 
the  southern  part  of  sec.  17,  Martin  Township  (T.  2  N.,  R.  11  W.),  there  is 
an  exposure  25  feet  in  depth  revealing  a  mass  of  cobble,  bowlderets,  and 
occasionally  bowlders,  in  a  bed  of  fine  gravel.  The  pebbles  are  much 
rounded,  and  in  places  are  held  together  by  a  calcareous  cement.  A  large 
part  of  them  are  granites  or  other  raetamorphic  or  igneous  rocks.  One- 
fourth  to  one-third  are  limestones,  slate,  and  other  local  rocks. 

A  well  on  ]\Ir.  Knickerbocker's  farm,  in  sec.  2,  Trowbridge  Township 
(T.  1  N.,  R.  13  W.),  penetrates  the  following  beds: 

Section  in  well  in  Trowbridge  Township,  Allegan  County,  Michigan. 

Feet. 

Soil  and  sand -0 

Soft  blue  clay  with  few  pebbles 4 

Cemented  gravel ~ . 

Loose  gravel 15 

Blue  clay  apparently  pebbleless 2 

Water-bearing  sand 3 


Depth . 


o:^ 


A  well  8U  rods  west  from  there,  on   Mr.  Ipe's  farm,  80  feet  in  dei)th, 
passed  through  gravelly  sand  with  ver)^  little  clay  adinixtiu-e.     Two  miles 


THE  VALPARAISO  MORAINIO  SYSTEM.  363 

east,  in  sec.  6,  Otsego  Township,  James  Henderson  lias  a  well  80  feet  deep 
almost  entirely  in  till,  as  follows: 

Section  in  ivell  in  Otsego  Township,  Allegan  County,  Michigan. 

Feet. 

Yellowisli  till 30 

Blue-gray  till 50 

Gravel  at  tjottciin. 

Depth 80 

Southwest  from  Allegan  in  Cheshire  Township  much  sand  occurs,  but 
not  in  level  tracts  as  on  the  Pine  Plains.  The  sand  has  a  billowy  surface 
and  associated  with  the  sandy  knolls  are  knolls  containing  much  till. 

A  well  in  sec.  19,  Cheshire  Township,  on  the  farm  of  W.  W.  Spencer, 
penetrates: 

Section  of  Spencer  icell  in  Cheshire  Toicnship,  Allegan  County,  Michigan. 

Feet. 

Soil  and  gravelly  clay  loam 4 

Sand 6 

Cemented  gravel 5 

Gravelly  sand 93 

Depth 108 

This  well  is  on  a  prominent  knoll  nearly  1 00  feet  hig-her  than  a  swamp 
80  rods  south  from  the  well  and  50  feet  above  the  general  elevation  of  the 
moraine  east  of  it.  Wells  in  the  adjoining  section  on  the  east  range  from 
20  to  35  feet  in  depth  and  penetrate  mainly  sand  and  gravel,  the  only 
clay  being  a  yellowish  clay  loam  near  the  surface.  In  the  northern  part  of 
Cheshire  Township  there  are  several  wells  which  are  largely  in  till.  One 
in  sec.  9,  118  feet  in  depth,  is  mostly  in  a  sandy  blue  clay,  but  the  exact 
section  was  not  preserved.  A  well  in  the  southeastern  part  of  the  same 
section,  36  feet  in  depth,  penetrates  the  following  beds : 

Section  of  icell  in  Sec.  36  Cheshire  Township,  Allegan  County,  Michigan. 

Feet. 

Yellowish  sandy  till 20 

Bine  sandy  till 14 

Water-bearing  sand 2 

This  till  tract  extends  northeast  nearly  to  the  city  of  Allegan,  lying 
between  the  outlet  of  Littlejohn  Lake  and  the  Kalamazoo  River. 

In  the  southern  part  of  Cheshire  Township,  Allegan  County,  and 
northern  part  of  Bloomingdale  Township,  Van  Buren  County  (T.  1  S., 
R.  14  W.),  wells  penetrate  20  to  35  feet  of  till,  and  are  then  in  sand  for 


364  THE  ILLINOIS  GLACIAL  LOBE. 

20  feet  or  more.     A  well  on  the  farm  of  Hon.  H.  Howard,  in  sec.  4,  Bloom- 
ing-dale Township,  has  the  following  section: 

Section  of  Howard  irell  in  Bloomingdale  Township,  Allegan  County,  Michigan. 

Feet. 

Loamy  clay,  with  much  sand  and  gravel 12 

Bluish-brown  till 15 

YelloTvish-gray  sand 20 

Cemented  gravel 3 

Coarse  yellow  sand 12 

Depth - 62 

A  well  across  the  road,  on  J.  Howard's  farm,  differs  in  section  from  the 
one  given,  having  no  cemented  gravel.  Its  dejith  is  54  feet.  Several  wells 
near  Eagle  Lake,  in  Cheshire  and  Bloomingdale  townships,  50  to  60  feet  in 
depth,  have  till  in  their  upper  portion  and  sand  in  the  lower.  East  of  Eagle 
Lake  is  a  heavy  deposit  of  till,  one  well  being  almost  entirely  in  blue-gray 
till  to  a  depth  of  112  feet,  obtaining  water  in  gravel  at  118  feet.  In  sec. 
20,  T.  1  N.,  R.  15  W.,  at  Lee  Station,  which  is  situated  at  the  southern 
border  of  the  "Pine  Plains,"  on  the  Chicago  and  Western  Michigan  Rail- 
road, a  well  120  feet  in  depth,  in  which  water  rises  nearly  to  the  surface, 
has  the  following  section: 

Section  in  well  at  Lee  Station,  Chicago  and  Western  Michigan  Railroad. 

Feet. 

Sand 8 

Hard  pebbly  blue  clay 30 

Bluish  quicksand 50 

Blue-gray  till 28 

Gravel - * 

Depth 120 

A  well  at  Grand  Junction,  in  Van  Buren  County,  penetrates  the  fol- 
lowing beds : 

Section  in  well  at  Grand  Junction,  Michigan. 

Feet. 

Soil  and  dry  yellow  saud 25 

Damp  saud  of  gray  color J 8 

Sand  and  gravel  at  bottom 5 

Depth 78 

Mail)-  wells  in  (leneva  Township,  2  to  5  miles  west  of  Grand  Junc- 
tion, are  in  till  to  a  dejjth  of  25  feet,  but  among  these  are  wells  largely  in 
sand  or  srravel.  East  from  Grand  Junction  for  several  miles  the  well  sec- 
tions  are  largelv  sand.     Near  Columbia  Station,  on  the  farm  of  Mr.  Reece, 


THE  VALPARAISO  MOEAINIC  SYSTEM.  365 

a  well  which  was  in  process  of  boring  at  the  time  of  my  visit  shows  the 

following  section : 

Section  near  Cohimbia  Station,  Michigan. 

Feet. 

90 
Yellow  sand 

Soft  blue  clay,  apparently  pebljleless 1° 

Bluish  sand,  exceediugly  fine ^ 

Depth "® 

This  sand  is  so  fine  that  it  can  not  be  screened  by  the  pump  strainer, 
and  renders  the  water  unfit  for  use. 

In  the  vicinity  of  Great  Bear  Lake,  sonth  of  Berlamont  Station,  there 
are  several  wells  100  feet  or  more  in  depth.  One  on  a  hill  three-fourths 
mile  west  from  the  north  end  of  the  lake  passes  through  100  feet  of  dry 
sand  and  gravel,  then  enters  water-bearing  sand  to  a'  depth  of  16  feet. 
Another  south  of  the  lake  in  western  Bloomingdale  Township  was  dug 
100  feet  through  sand  and  gravel  without  obtaining  water.  A  well  south- 
west of  the  lake,  in  sec.  25,  Columbia  Township,  on  a  hill  rising  100  feet 
above  the  lake,  is  125  feet  in  depth  and.  largely  in  dry  sand  and  gravel. 
Between  Great  Bear  Lake  and  Bloomingdale  wells  are  sunk  mainly  in  till, 
both  yellow  and  blue,  but  are  only  40  to  60  feet  in  depth. 

A  well  2  miles  south  of  Bloomingdale,  on  J.  G.  Miller's  farm,  is  110 
feet  deep,  passing  tln'ough  blue-gray  till  nearly  the  whole  depth.  As  a  rule 
Bloomingdale  Township  is  underlain  by  till  to  an  average  depth  of  40  feet, 
the  only  notable  exception  being  the  eastern  tier  of  sections,  where  wells 
are  largely  in  sand  and  gravel.  This  tier  of  sections  is  more  elevated  than 
the  remainder  of  the  township. 

A  well  at  Mr.  Merrifield's,  IJ  miles  north  of  Bloomingdale,  presents  the 
following  exceptional  section: 

Section  in  icell  near  Bloomingdale,  Michigan. 

Feet. 

Soil  and  dry  yellow  sand - 

Quicksand 

Blue-gray  till 

Cemented  gravel 

Yellowish  till ^*^ 

Quicksand  of  gray  color 

White  sand  with  water 

Water-bearing  gravel 

Depth ^^ 

A  well  3  miles  south  of  Gobies,  in  Waverly  Township,  on  a  prominent 
point  called  Covey  Hill,  is  109  feet  in  depth,  and  the  entire  section  is  made 


366  THE  ILLINOIS  GLACIAL  LOBE. 

up  of  sand  beds  alternating  with  thin  layers  of  cemented  gravel.  Wells  in 
Grobles,  and  for  a  mile  or  two  north  and  south  from  this  village,  are  from 
50  to  60  feet  in  depth.  They  penetrate,  jvist  below  the  soil,  a  crust  of 
cemented  sand,  gravel,  and  clay,  called  "hardpau,"  about  2  feet  in  thick- 
ness, beneath  which  are  alternate  beds  of  sand  and  gravel,  loose  and  dry 
as  a  rule,  but  cemented  slightly  in  places.  Usually  a  cemented  layer  is 
passed  through  just  above  the  water.  Wells  in  the  gravel  plain  from  1  to  3 
miles  northeast  of  Gobies  pass  throvigh  2  to  5  feet  of  hard,  pebbly,  reddish 
clay  called  "hardpan."  Below  this  is  sand,  loose  gravel,  and  cemented 
gi'avel.  Wells  are  about  40  feet  in  depth  and  seldom  penetrate  any  till  or 
clay  except  that  just  beneath  the  soil. 

A  well  in  the  northern  part  of  sec.  18,  Almena  Township  (T.  2  S., 
E,.  13  W.),  on  the  farm  of  Robert  Clark,  is  86  feet  in  depth,  and  has  the 
following  section: 

Section  of  Clark  well  in  Almena  Township,  Van  Buren  County,  Michigan. 

*  Feet. 

Loamy  sand 14 

Quicksand 2 

Blue-gray  till 40 

Cemented  gravel 14 

Fine  sand 16 

Total 86 

Gravel  and  water  at  bottom. 

A  large  part  of  Waverly  Township  is  underlain  by  till.  Nearly  half 
of  the  township  is  swamp  laud  with  very  few  inhabitants,  but  the  portion 
not  swampy  (northeastern  pai-t)  has  wells  35  feet  or  more  in  depth  almost 
entirely  in  till.  This  till  is  yellow  or  oxidized  to  a  depth  of  at  least  15  feet. 
An  elevated  tract  in  the  northwestern  part  of  the  township  has  a  loamy 
clay  2  to  4  feet  and  occasionally  10  to  12  feet  in  depth,  below  which  is  a 
reddish-yellow  till.     Wells  are  only  20  to  25  feet  in  depth. 

There  is  a  small  flowing  well  district  in  the  swamp  along  the  Pawpaw 
River,  in  the  southwestern  part  of  the  township.  All  the  wells  of  which 
records  were  obtained  are  in  the  southern  part  of  sec.  30.  They  are  each 
about  50  feet  in  depth.  In  one  well  the  water  rises  nearly  10  feet  above 
the  surface,  but  in  the  others  only  1  to  4  feet.  They  peneti'ate  a  slightly 
pebbly  blue  clay  nearly  the  whole  depth,  there  being  scarcely  any  yellow 
clay  even  at  the  surface. 


THE  VALPARAISO  MOEAINIC  SYSTEM.  367 

On.  the  elevated  tract  north  of  Pawpaw  River,  in  Lawrence,  Hartford, 
and  Arhngton  townships  (T.  3  S.,  Rs.  15  W.  and  16  W.,  and  T.  2  S.,  R.  15  W.), 
a  considerable  portion  has  but  6  or  8  feet  of  till,  beneath  which  is  dry  sand 
or  g-ravel.  In  some  cases  wells  are  sunk  100  feet  in  this  sand  and  gravel 
before  reaching  water,  but  the  majority  of  them  obtain  water  at  40  to  50 
feet.  On  the  elevated  land  immediately  north  of  the  village  of  Lawrence 
there  is  much  sand  at  the  surface.  Wells  are  often  20  to  40  feet  in  sand. 
In  some  places  the  sand  is  underlain,  by  10  to  20  feet  of  bluish  till,  and  this 
in  turn  by  dry  sand  or  gravel,  becoming  water-bearing  toward  the  bottom; 
beneath  this  lower  sand  is  a  blue  till  of  various  depths. 

Wells  in  southern  Arlington  Township,  near  the  northern  part  of  the 
elevated  tract,  are  frequently  80  feet  and  occasionally  160  feet  in  depth. 
A  well  in  sec.  23,  162  feet  in  depth,  penetrates: 

Section  of  well  in  sec.  23,  Arli7igt07i  Township,  Van  Bur  en  County,  Michigan. 

Peet. 

Eeddisli-brown  till 40 

Quicksand 10 

Blue-gray  till 110 

Gravel 2 

Total 162 

In  the  same  section  is  a  well  80  feet  in  depth,  which  penetrates  the 
following  beds: 

Section  of  well  in  sec.  23,  Arlington  Toicnship,  Van  Buren  County,  Michigan. 

Feet. 

Dry  sand 40 

Cobble  and  gravel 15 

Sand  of  gray  color,  streaked  with  red,  containing  limestone  concretions 25 

Total 80 

As  a  rule,  there  is  12  to  15  feet  of  reddish-brown  till  above  the  sand 
and  occasionally  40  to  50  feet,  but  in  places  it  is  wanting  entirely,  as  in  the 
above  section.     A  well  in  sec.  20  has  the  following  section: 

Section  of  well  in  sec.  20,  Arlington  Toicnship,  Van  Buren  County,  Michigan. 

reet. 

Yellowish-brown  till 10 

Cemented  gravel 8 

Dry  sand  and  gravel,  with  cemented  gravel  near  bottom 35 

Brownish  till,  with  thin  beds  of  cemented  gravel  and  quicksand 30 

Water-bearing  gravel __ 2 

Depth 85 


368  THE  ILLINOIS  GLACIAL  LOBE. 

A  well  ou  sec.  21,  one-half  mile  east  of  the  above,  i.s  125  feet  iu  depth 
and  is  almost  entirely  iu  sand  and  gravel.  This  well  is  on  a  prominent 
knoll.  So  far  as  observation  was  extended,  these  knolls  quite  unifoiTuly 
show  a  great  depth  of  sand  and  gravel,  with  but  little  till,  and  that,  too, 
when  till  is  found  on  the  adjacent  lower  lands. 

On  the  elevated  land  north  of  Hartford,  in  sec.  11,  Hartford  Township, 
a.,  a  height  of  85  feet  (aneroid)  above  the  flood  plain  of  Pawpaw  River,  on 
the  farm  of  Samuel  Keine,  a  well  87  feet  in  depth  penetrates: 

Section  in  Keine  icell  north  of  Hartford.,  Van  Btiren  County,  Michigan, 

Feet. 

Gravelly  sandy  clay 10 

Yellowish  till 12 

Cemented  gravel  with  thin  clay  beds 60 

Loose  gravel  with  water 5 

Total 87 

A  well  across  the  road  was  sunk  to  a  depth  of  160  feet.  For  a  depth 
of  80  feet  its  section  is  similar  to  the  above ;  below  this  there  is  a  bed  of 
blue  bowlder  clay  nearly  80  feet  thick,  which  is  underlain  by  water-bearing 
gi'avel.  It  was  on  Mr.  Keine's  farm,  at  a  level  about  35  feet  lower  than  the 
siu'face  at  the  well,  that  the  huge  limestone  bowlder  noted  above  (p.  357) 
was  found. 

In  Bangor  Township  and  in  the  vicinity  of  Breedsville,  in  Columbia 
Township,  deep  wells  are  rare,  the  usual  depth  being  but  25  to  30  feet.  In 
some  cases  the  wells  are  largely  in  till,  but  in  others  the  section  is  prin- 
cipally gravel.  There  is  but  little  sand  on  the  surface  in  Bangor  Town- 
ship, compared  with  that  in  Columbia  Township,  and  it  is  exceptional  to 
pass  thi-ough  much  sand  in  sinking  a  well  unless  it  be  on  a  high  knoll. 
The  deepest  well  in  this  township  of  which  a  record  Avas  obtained  is  iu 
sec.  17,  on  the  highest  knoll  in  the  western  part  of  the  township,  and  is 
interestino-  since  it  is  but  a  few  rods  distant  from  one  of  the  large  sandstone 
bowlders  noted  above.     The  following  is  the  well  section: 

Section  of  well  in  sec.  17,  Bangor  Toirnship,  Van  Burcn  County,  Michigan. 

Feet. 

yellowish  till 5 

Dry  8and 15 

Coarse  sand  with  water - :^i 

Fine  sand 7 

Brownish  day 8 

Sand 6fi 


Depth . 


1(11 


THE  VALPARAISO  MORAINIC  SYSTEM.  369 

A  prominent  knoll  about  a  mile  east  of  Bangor,  rising  125  feet  above 
the  station  of  the  Chicago  and  West  Michigan  Railroad,  or  775  feet  above 
tide,  contains  much  fine  sand  which  has  been  used  in  the  iron  fmiiace  in 
Bangor  as  molder's  sand.  There  are  gravel  beds  interstratified  with  it. 
The  exposure  does  not  show  the  deeper  structure  of  the  hill. 

In  Watervliet  Township  and  in  western  Hartford  Township  the  western 
portion  of  the  morainic  belt  has  a  deposit  of  till  which  is  penetrated  to  a 
depth  of  20  to  40  feet  in  wells;  but  in  eastern  Hartford  and  Lawrence 
townships  the  structure  changes  on  rising  to  the  higher  jjortions  of  the 
moraine,  and  wells  are  in  sand  or  gravel  much  of  their  depth.  There  is, 
however,  on  the  lowland  along  Pawpaw  River  from  Hartford  to  Watervliet 
a  sandy  belt  a  mile  or  more  in  width  in  which  wells  penetrate  sand  or  gravel 
to  a  de^jth  of  20  to  40  feet  without  encountering  till.  At  Watervliet  this 
sand  belt  is  very  narrow,  wells  80  rods  south  from  the  railway  station  pene- 
trating much  till.  The  sand  and  gravel  is  confined  to  a  plain  along  the 
river,  which  stands  at  about  the  level  of  the  highest  beach  of  Lake  Chicago. 
The  ridges  and  undulatory  tracts  both  north  and  south  from  this  plain  con- 
tain much  till. 

The  rolling  belt  southwest  from  Coloma  has  a  great  depth  of  sand,  so 
that  wells  35  to  50  feet  in  depth  penetrate  little  else.  In  the  village  of 
Coloma  wells  encounter  a  variety  of  beds,  of  which  the  following  section  of 
a  well  at  Mr.  Abram  Smith's  may  be  taken  as  representative : 

Section  of  well  at  Coloma,  Berrien  County,  Michigan. 

Feet. 

Clay  loam  of  yellow  color 8 

Dry  gravel  and  sand  with  bo wlderets  and  bowlders  embedded 13 

Cemented  gravel 8 

Blue  clay,  apparently  pebbleless : 9 

Depth 38 

Wells  on  the  ridge  on  the  south  side  of  the  Pawpaw  River,  between 
Coloma  and  Watervliet,  disclose  much  variation  in  structure.  One  well 
maj;  be  largely  in  till,  another  on  the  same  farm  principally  in  sand  or 
gravel,  while  a  third  may  have  both  assorted  and  unassorted  drift.  The 
surface  is  more  uniformly  coated  with  a  clay  loam  east  of  Coloma  than  it 
is  southwest.  A  well  on  the  north  side  of  Pawpaw  River,  near  Pawpaw 
Lake,  on  the  farm  of  Mr.  Huntoon,  peneti'ates: 
MON  xxxviii 24 


370  THE  ILLINOIS  GLACIAL  LOBE. 

Section  in  well  near  Pauyaw  Lake,  Michigan. 

Feet. 

Yellowish  till 10 

Blue-gray  till 10 

Dry  sand 20 

Water-bearing  gravel 4 

Depth 44 

A  well  at  Hillside  stock  farm,  on  the  north  side  of  Pawpaw  River, 
opposite  Watervliet,  penetrates  till,  principally  of  a  blue-gray  color,  to  a 
depth  of  40  feet.  A  well  on  the  northwest  side  of  Pawpaw  Lake,  in  the 
east  part  of  sec.  9,  125  feet  deep,  penetrates  till  120  feet. 

In  the  portion  of  Hartford  Township  east  of  the  "vallage,  wells  are  in 
sand  and  gravel  on  the  elevated  land,  while  west  from  the  -callage  the  elevated 
tracts  are  covered  with  a  quite  heavy  deposit  of  till.  Pine  Creek  seems  to 
mark  the  division  line,  there  being  more  sand  and  gravel  east  of  the  creek 
than  west  of  it. 

A  well  in  sec.  17,  Lawrence  Township,  on  a  prominent  portion  of  the 
moraine  100  feet  or  more  above  Pawpaw  River,  penetrates  the  following 
beds: 

Section  oftcell  hi  sec.  17,  Laicrence  Toicnship,  Van  Btiren  County,  Michigan. 

Feet. 

Yellowish  till  .. 10 

Dry  sand 70 

Quicksand 40 

Blue  clay;  no  pebbles  observed , 40 

White  dry  sand "0 

Depth 230 

A  well  in  the  southwestern  part  of  the  same  section,  103  feet  in  depth, 
penetrates  only  8  feet  of  till,  the  remainder  being  sand. 

A  well  in  the  northeastern  part  of  sec.  20  of  the  same  township,  80 
feet  in  depth,  penetrates  but  7  feet  of  till.  The  sand  is  coarse  at  top  and 
becomes  finer  below.  In  the  lower  part  of  the  bed  it  was  fine  as  flom-. 
The  pipe  was  di-awn  up  to  within  57  feet  of  the  surface,  where  the  sand 
was  sufficiently  coarse  to  be  screened  by  the  pump  strainer.  Several  other 
wells  in  tlie  soutliwestern  part  of  Lawrence  Township  are  characterized  b)- 
a  slight  depth  of  yellow  till  underlain  b}-  a  great  depth  of  sand. 


THE  VALPARAISO  MOEAINIC  SYSTEM.  371 

T.  0.  Sweet,  a  well  borer  residing  at  Lawrence,  states  that  wells  in  the 
village  of  Lawrence  are  usually  25  to  40  feet  in  depth  and  penetrate  the 
following  beds: 

Generalized  section  of  wells  at  Laivrence,  Michigan. 

Feet. 

Eeddisli  till  and  saudy  clay 7-18 

Yellow  till 3-7 

Quicksand 9-14 

Blue-gray  till  at  bottom. 

In  some  cases  the  quicksand  extends  to  a  depth  of  40  feet  or  more,  so 
that  its  bottom  is  not  reached. 

On  the  elevated  land  south  of  Lawrence  thei-e  is  12  to  20  feet  of  yel- 
lowish till  with  sandy  gravel  interbedded,  and  beneath  this  is  a  blue  till 
mixed  with  blue  quicksand.  Wells  in  some  cases  penetrate  this  quicksand 
to  a  depth  of  100  feet. 

On  the  outer  border  of  the  moraine,  in  sec.  1,  Lawrence  Township,  on 
the  farm  of  Mr.  Hutchins,  a  well  125  feet  deep  penetrated  sand  and  gravel 
its  entire  depth  and  encountered  many  bowlders  and  bowlderets.  A  well 
at  Mr.  Whipple's,  in  the  river  valle}^  half  a  mile  north  and  about  120  feet 
lower  at  the  surface  than  the  preceding,  penetrates  a  yellow  till  12  to  15 
feet,  below  which  is  blue  clay,  apparently  pebbleless,  penetrated  to  a  depth 
of  25  feet.  Mr.  Whipple  states  that  the  valley  of  Pawpaw  River,  in 
northeastern  Lawrence  Township,  is  underlaid  by  clay  of  a  blue  color  and 
also  a  blue  quicksand.  In  one  instance  a  well  was  driven  into  this  quick- 
sand 80  feet  without  reaching  the  bottom. 

A  well  near  the  border  of  the  Pawpaw  Valley,  20  feet  or  more  above 
it,  on  the  slope  of  the  moraine  in  the  eastern  part  of  sec.  11,  Lawrence 
Township,  has  the  following  section: 

Section  of  well  in  sec.  11,  Lawrence  Toumship,  Van  Buren  County,  Michigan. 

Feet. 

Sand  and  gravel 18-20 

Blue-gray  till 48 

Coarse  sand  and  fine  gravel 14 

Deptli 72 

A  well  about  60  rods  north  from  this,  at  nearly  the  same  level,  pene- 
trated no  thick  bed  of  till,  but  instead  alternate  beds  of  clay  and  sand  or 
clay  and  gravel  to  a  depth  of  76  feet. 


372  THE  ILLINOIS  GLACIAL  LOBE. 

A  well  ou  the  border  of  the  overvvash  apron  in  the  southeastern  part  of 
sec.  12,  Lawrence  Township,  penetrated  coarse  gravel  and  cobble  84  feet 
before  striking  water,  and  this  well  has  the  peculiarity  of  freezing  over  in 
winter.  Probably  the  outside  air  has  access  through  the  spaces  in  the  gravel 
and  cobble  beds  to  the  water  in  the  well. 

Wells  along  the  outer  border  of  the  moraine  in  southeastern  Lawrence 
Township  (T.  3  S.,  R.  15  W.)  and  northwestern  Hamilton  (T.  4  S.,  R.  15  ^Y.) 
penetrate  more  till  than  do  those  nearer  the  Pawpaw  River,  many  wells  25 
to  40  feet  in  depth  being  largelj^  in  till,  but  there  is  occasionally  a  small 
tract  in  which  no  till  occurs.  In  such  a  tract  in  sec.  5,  Hamilton  Township, 
there  are  two  wells,  each  110  feet  deep,  which  penetrate  sand  and  quick- 
sand for  100  feet  before  reaching  any  gravel.  A  well  in  sec.  2,  Keeler 
Township,  85  feet  in  depth,  is  entirely  in  sand,  while  on  adjoining  farms 
wells  penetrate  a  considerable  depth  of  till. 

The  overwash  apron  which  borders  the  moraine  in  Pawpaw,  Lawrence, 
Hamilton,  and  Keeler  townships  (Ts.  3  S.,  R.  14,  3  S.,  R.  15,  4  S.,  R.  15, 
and  4  S.,  R.  16),  Van  Buren  County,  has  wells  25  to  70  feet  deep  which 
seldom  penetrate  any  till,  but  are  in  assorted  material,  usually  gravel,  their 
entire  depth.  There  is  a  hardpan  of  slightly  cemented  gravelly  clay  loam 
2  feet  or  more  in  depth  just  beneath  the  soil  over  much  of  this  overwash 
apron.  At  Keelerville  wells  are  obtained  at  30  to  40  feet.  They  penetrate 
15  feet  of  loose  gravel  and  sand  just  beneath  the  hardpan,  then  12  to  15 
feet  of  slightly  cemented  gravel,  and  stiike  water  in  uncemented  gi-avel. 

On  the  moraine  southwest  of  Keelerville  are  wells  45  to  100  feet  in 
depth  which  penetrate  but  little  till  as  compared  with  those  northeast  of  the 
town.  A  well  5  miles  distant,  in  the  northwestern  corner  of  Cass  County, 
was  driven  to  a  depth  of  190  feet  and  passed  first  through  a  bed  of  gravel, 
then  through  125  feet  of  quicksand. 

Immediately  west  of  this  elevated  gravelly  portion  of  the  moraine 
which  passes  from  Sister  Lakes  across  the  northwestern  corner  of  Cass 
County  is  a  tract  of  land  along  Pipestone  Creek  whose  surface  is  100  to  130 
feet  lower  than  the  moraine,  and  in  a  belt  of  this  lower  tract  between 
Pipestone  Creek  and  the  higher  land  extending  for  4  or  5  miles  south  of 
Pipestone  Lake  several  flowing  wells  have  been  obtained.  Information 
concerning  them  was  given  by  Robert  Kingsley,  a  well  borer,  who  has  been 
employed  in  sinking  the  wells.  They  usually  range  in  depth  from  80  to 
125  feet,  and  are  mainly  through  till,  yellowisli  brown  for  15  to  20  feet  and 


THE  VALPARAISO  MOEAmiC  SYSTEM.  373 

of  blue-gray  color  65  to  100  feet.  Beneath  this  till  there  is  usually  a 
ferruginous  crust  a  few  inches  in  thickness  which  caps  the  water  vein. 
The  water  rises  in  each  well  8  to  10  feet  above  the  surface  and  flows 
several  gallons  per  minute.     It  is  slightlj^  chalybeate. 

Near  the  corner  of  sees.  1  and  2,  11,  and  12,  Pipestone  Township,  are 
two  flowing  wells,  one  56  feet  and  the  other  68  feet  in  depth.  There 
are  two  wells  on  the  south  side  of  the  SW.  ^  of  sec.  11  which  are  75  to  80 
feet  in  depth  and  flow  10  to  15  gallons  each  per  minute.  A  well  in  the 
southwestern  corner  of  sec.  22  only  24  feet  in  depth  flows  about  5  gallons 
per  minute,  the  water  rising  but  2^  feet  above  the  surface.  A  well  in  the 
NW.  4  of  sec.  27,  about  25  feet  deep,  flows  3  gallons  per  minute,  the  water 
rising  2  to  3  feet.  A  well  in  the  SE.  ^  of  sec.  2,  36  feet  in  depth,  flows  15 
gallons  per  minute  at  an  elevation  of  3  feet  above  the  surface.  It  penetrates 
a  yellowish-brown  till  nearly  to  the  water  vein.  In  the  SW.  ^  of  sec.  2  a 
well  150  feet  in  depth  flows  but  3  gallons  in  five  minutes.  This  is 
decreasing  in  flow.     It  is  the  pioneer  well  and  began  flowing-  about  1877. 

The  surface  of  this  flowing  well  district  is '  gently  undulatory,  with 
frequent  oscillations  of  10  to  16  feet  in  20  to  30  rods.  The  wells  as  a  rule 
are  on  low  land  not  more  than  10  or.  15  feet  above  the  level  of  Pipestone 
Creek. 

Northwest  of  this  flowing  well  district  and  uniting  with  the  elevated 
tract  which  forms  its  eastern  boundary  is  a  tract  of  high  land  which  is 
characterized  by  a  large  amount  of  sand.  Many  wells  are  60  to  80  feet  or 
more  in  sand,  but  in  the  midst  of  the  sandy  belt  are  spots  where  a  consid- 
erable depth  of  till  is  found.  For  example,  a  well  in  the  northwest  corner 
of  sec.  13,  Bainbridge  Township  (T.  4  S.,  R.  17  W.),  penetrates: 

Section  of  well  in  sec.  13  Bainbridge  Township,  Berrien  County,  Michigan. 

Feet. 

Bro wnish-yellow  till 10-12 

Blue-gray  till 15 

Water-bearing  sand  at  bottom.  8-10 

Depth 37 

A  well  on  the  south  side  of  sec.  12  of  the  same  township  penetrates: 
Section  of  icell  in  sec.  12  Bainbridge  Townshij),  Berrien  Comity,  Michigan. 

Feet. 

Brownish-yellow  till 8-10 

Blue-gray  till,  with  thin  beds  of  quicksand 110 

Gravel 5 

Depth 125 


374  THE  ILLINOIS  GLACIAL  LOBE. 

This  till  tract  fronts  the  south  border  of  a  swamp  for  2  or  3  miles. 
The  till  extends  back  but  a  short  distance  toward  the  south,  soon  giving 
place  to  sand. 

A  very  small  tract  underlain  by  till  is  found  near  the  corner  of  sees.  14, 
15,  22,  and  23  of  this  township  (Bainbridge).  It  is  less  than  a  square  mile 
in  extent.     A  well  in  the  southwestern  corner  of  sec.  14  penetrates: 

Section  of  well  in  sec.  14  Bainbridge  Township,  Berrien  County,  Michigati. 

Feet. 

Yellowish  till 6 

Blue-gray  till H" 

Gravel  at  bottom  of  well. 

Depth , Ilt5 

A  mile  west  from  here,  at  Bainbridge  Center,  wells  are  almost  entirely 
in  sand  to  a  depth  of  60  ''eet.  In  the  sand  are  thin  beds  of  slightly 
cemented  gravel.  This  sandy  tract  extends  west  a  mile  or  more  from  Bain- 
bridge Center  and  nearly  as  far  north.  A  well  in  the  western  part  of  sec. 
10,  on  the  farm  of  A.  Woodruff,  penetrates: 

Section  of  Woodruf  ivell  in  Bainbridge  ToionsMp,  Berrien  County,  Michigan. 

Feat. 

Brownsand - 5 

Brownish-yellow  till '  12-14 

Gray  sand,  with  occasional  nodules  and  clay  balls 48-50 

Brownish  till,  very  hard 12 

Gravel  and  sand  with  water  at  bottom. 

Depth '. J 81 

A  well  across  the  road,  75  feet  in  depth,  has  a  similar  section. 
.    In  western  Bainbridge  and  eastern  Benton  townships  (Ts.  4  S.,  R.  17 
W.,  and  4  S.,  R  18  W.)  wells  vary  much  in  the  character  of  their  section, 
some  being  almost  wholly  in  till,  others  penetrating  little  beside  gravel  and 
sand,  and  this  is  often  true  where  the  whole  surface  appears  sandy. 

In  the  northeastern  part  of  Bainbridge  Township,  about  3  miles  due 
south  of  Water vliet,  are  three  flowing  wells.  They  are  only  16,  28,  and 
40  feet  deep.  Most  of  their  section  is  in  blue-gray  till,  and  the  water 
comes,  it  is  said,  from  caverns  in  the  clay.  The  water,  which  is  quite 
chalybeate,  rises  2  to  4  feet  above  the  surface. 

In  the  portion  of  the  Valparaiso  moraine  in  Berrien  County  south  from 
the  latitude  of  St.  Joseph,  Michigan,  no  records  of  wells  were  collected. 
The  portion  east  from  Si;.  Joseph  River  apparently  consists  largely  of  sand. 


THE  VALPARAISO  MORAINIC  SYSTEM.  375 

and  gravel.     In  the  portion  west  of  the  river  till  apparently  predominates 
over  sand  and  gravel,  though  the  inner  border  is  in  places  quite  sandy. 

CHARACTEE   OP   THE   OUTWASH. 

The  position  of  the  Valparaiso  morainic  system  is  favorable  for  the 
discharge  of  water  from  the  western  and  soiithern  bordei's  and  to  some 
extent  from  the  eastern  border.  On  the  west  the  Fox,  Dupage,  and  Des 
Plaines  rivers,  and  small  tributaries  of  the  Des  Plaines,  lead  directly  away 
from  the  border  of  the  morainic  system,  while  on  the  south  the  Kankakee 
and  its  tributaries  afford  a  line  of  discharge  toward  the  west.  On  the  east 
the  streams  now  draining  the  border  of  this  morainic  system  are  ti'ibutary 
to  rivers  which  flow  through  it  into  Lake  Michigan,  but  it  seems  probable 
that  for  at  least  a  portion  of  the  time  of  the  formation  of  the  Valparaiso 
morainic  system  the  drainage  along  Dowagiac  River  and  also  much  of  the 
St.  Joseph  River  was  tributary  to  the  Kankakee  instead  of  the  lower  St. 
Joseph  River. 

Along  each  of  the  main  valleys  which  border  the  morainic  system,  or 
lead  away  from  it,  a  large  amount  of  gravelly  material  has  been  deposited. 
Taking  these  valleys  in  turn,  beginning  with  Fox  River  and  passing  south 
and  east,  the  features  are  as  follows: 

On  Fox  River,  from  the  Wisconsin  line  southward  nearly  to  the  south 
line  of  Lake  and  McHenry  counties,  there  are  broad  marshes  underlain  by 
sand  and  silt,  and  the  stream  has  very  little  fall.  Professor  Rolfe's  baro- 
metric survey  indicates  that  there  is  a  fall  of  but  30  feet  in  the  30  miles 
occupied  in  crossing  these  counties.  In  southeastern  McHenry  County 
heavy  deposits  of  gravel  and  cobble  set  in,  which  lead  down  the  valley  in 
the  form  of  terraces  through  the  entire  length  of  Kane  County,  a  distance 
of  30  miles.  The  stream  in  this  distance  makes  a  descent  of  125  feet, 
while  the  gravelly  terraces  make  an  even  greater  descent,  their  elevation 
at  Elgin  being  nearly  100  feet  and  at  Aurora  only  40  to  60  feet  above  the 
stream.  Heading  as  these  gravel  deposits  do  near  the  point  where  the 
Valparaiso  moraine  leads  away  from  the  Fox  River  Valley,  and  standing  as 
they  do  above  the  marshy  tracts  along  the  portion  of  the  vallej-  imme- 
diately to  the  north,  there  seems  to  be  little  question  that  they  represent  an 
outwash  from  the  ice  sheet.  The  gravel  is  of  medium  coarseness  through- 
out the  greater  part  of  its  depth,  but  in  places  the  surface  portion  consists 


376  THE  ILLINOIS  GLACIAL  LOBE. 

of  cobble  and  coaree  gravel.  The  belt  occupies  a  width  of  a  mile  or  more 
and  the  gravel  is  in  places  built  up  60  to  75  feet.  In  other  places  it  has  a 
depth  of  only  10  or  20  feet.  The  avei'age  depth  is  probably  not  less  than 
40  feet. 

On  the  west  Dupage  River,  which  throughout  much  of  its  course  fol- 
lows the  outer  border  of  the  Valparaiso  morainic  system,  there  are  deposits 
of  gravel  and  cobble  occupying  a  belt  a  mile  or  so  in  width,  which  connect 
at  the  south  with  a  still  broader  belt  of  gravel.  On  the  slopes  of  the 
moraine  immediately  east  of  this  stream  there  are  numerous  gravelly  knolls, 
which  connect  with  the  plain  of  gravel  on  the  borders  of  the  river  in  such 
manner  as  to  indicate  that  they  should  be  included  with  the  glacifd  drain- 
age, though  they  suffered  so  little  transportation  as  to  make  the  term 
"outwash"  seem  scarcely  appropriate.  The  lower  Dupage  River  appears 
to  have  been  an  avenue  of  discharge,  not  only  for  glacial  waters  from  the 
Upper  Dupage  but  also  from  the  neighboring  section  of  the  Des  Plaines 
River,  as  indicated  below. 

On  the  Des  Plaines  Valley  the  gravel  tilling  apparently  reached  such  a 
height  that  a  delta-like  system  of  streams  was  formed  in  the  vicinity  of 
Joliet,  some  of  which  were  thi'own  across  the  low  di\'ide  on  the  west  into 
the  Dupage  River.  Along  the  courses  of  the  glacial  streams,  well-defined 
valleys  were  formed  which  are  now  occupied  by  marshes  and  insignificant 
tributaries  of  the  Des  Plaines  and  Dupage.  The  position,  size,  and  relation 
of  these  abandoned  valleys  are  set  forth  on  the  Joliet  topographic  sheet  of 
this  Survey.  One  valley  occupied  by  the  Isle  la  Cache  Creeks  has  a  summit 
level  slightly  above  the  600-foot  contour;  another,  drained  by  Mink  Creek, 
has  a  summit  level  about  620  feet;  a  third,  now  largely  uudi'ained  but  con- 
necting at  the  west  with  Rock  Run,  was  cut  down  to  about  575  feet.  The 
one  drained  by  Mink  Creek  seems  to  have  been  cut  no  lower  than  the  upper 
limit  of  the  gravel  filling  on  the  neighboring  portion  of  the  Des  Plaines,  but 
the  others  were  cut  a  few  feet  below  the  level  of  that  filling. 

On  the  immediate  outer  border  of  the  main  ridge  of  the  Valparaiso 
morainic  system,  near  Romeo,  the  gravel  filling  reaches  about  620  feet,  and 
this  appears  to  be  the  head  of  the  gravel,  though  the  great  excavation  sub- 
sequently made  by  the  Chicago  Outlet  leaves  the  question  of  the  precise 
head  somewhat  uncertain.  Upon  passing  down  the  Des  Plaines  the  gravel 
filling  shows  a  marked  descent.     At  Joliet  Mound,  2  miles  below  Joliet,  it 


THE  VALPARAISO  MOEAINIC  SYSTEM.  377 

has  fallen  to  580'  feet  and  at  Channahon  to  570  feet,  a  fall  of  60  feet  in  a 
distance  of  about  20  miles.  There  is  a  corresponding'  fall  on  the  lower 
Dupage,  the  surface  of  the  gravel  in  the  vicinity  of  Plaintield  being  about 
610  feet,  at  Grinton  590  feet,  and  at  Channahon  570  feet. 

The  deposits  along  the  Dupage  and  Des  Plaines  rivers  consist  in  the 
main  of  coarse  gravel  and  cobble,  much  of  the  finer  material  having-  been 
swept  away  by  the  strong  current.  Excellent  exposures  are  to  be  seen  in 
the  gravel  pits  near  Plainfield  on  the  Dupage,  and  in  numerous  small 
gravel  pits  along  the  border  of  the  Des  Plaines  both  above  and  below 
Joliet.  One  of  the  largest  on  the  Des  Plaines  is  found  in  an  island-like 
remnant  of  the  old  terrace  known  as  Joliet  Mound,  about  2  miles  below 
the  city  of  Joliet,  on  the  west  side  of  the  river.  At  the  s(5utheast  end  of 
this  mound  the  following  section  is  exposed : 

Section  of  Joliet  Mound,  Will  County,  Illinois. 

Feet. 

Surface  coating  of  silty  clay 1-4 

Coarse  gravel  and  cobble 10-12 

Sandy  gravel  of  medium  coarseness,  cemented  in  places 25-30 

Fine  sand  or  loam 4 

Blue  pebbleless  clay,  laminated,  calcareous 8-10 

Bowlder  bed,  containing  clay  balls  and  a  sandy  clay  matrix,  extending  to  river  level  on  east 
side  of  mound,  but  underlain  at  slight  depth  by  limestone  at  west  side 5-20 

It  is  thought  that  the  bowlder  bed  may  be  a  result  of  interglacial  erosion 
of  a  till  sheet.  The  blue  pebbleless  clay  which  overlies  it  is  apparently  a 
still-water  deposit,  formed  perhaps  before  the  ice  sheet  had  reached  such  a 
stage  of  melting  as  to  produce  vigorous  drainage.  The  upper  member 
appears  to  indicate  a  deposit  by  a  stream  whose  vigor  was  greatest  toward 
the  close  of  deposition,  for  at  the  top  the  cobble  is  swept  almost  free  from 
sand.  The  change,  however,  may  have  been  brought  about  by  shifting  of 
the  main  current  of  the  stream,  the  coarse  material  being  deposited  over 
portions  of  the  bed  which  had  before  been  outside  the  main  current.  As 
only  occasional  remnants  of  this  gravel  filling  are  preserved,  it  is  impossible 
to  determine  the  original  variations  in  coarseness  in  a  section  passing  across 
the  valley. 

The  deposits  of  gravel  along  this  valley  terminate  very  abruptly  at 
the  south,  near  Channahon,  there  being  only  a  fine  sand  on  the  plain  in  the 
Morris  Basin  at  the  head  of  the  Illinois.  This  feature  is  apparently  due  to 
the  presence  of  a  lake  in  the  low  country  about  the  head  of  the  Illinois 


378  THE  ILLINOIS  GLACIAL  LOBE. 

River.  The  beaches  of  this  lake  and  its  western  discharge  throug-h  the 
Mai-seilles  moraine  down  the  Ilhnois  have  ah-eady  been  discussed.  The 
level  of  the  beaches  corresponds  so  nearly  with  that  of  the  upper  limit  of 
the  valley  filling  at  Chaunahon  that  the  latter  may,  with  some  confidence, 
be  considered  a  delta-like  accumulation  at  the  north  border  of  the  lake. 

It  is  probable  that  each  of  the  small  tributaries  of  the  Kankakee, 
which  head  in  the  Valparaiso  moraine,  and  also  eastern  tributaries  of  the 
Des  Plaines,  aff"orded  lines  for  escape  of  glacial  waters,  but  the  writer  has 
not  examined  these  valleys  with  sufficient  thoroughness  to  determine  the 
effect  of  the  glacial  waters.  On  the  valley  of  Hickory  Creek,  which  enters 
the  Des  Plaines  at  Joliet,  a  gravel  filling  is  conspicuous  from  the  outer 
border  of  the  rhain  moraine  in  sec.  17,  New  Lenox  Township,  to  the  mouth 
of  the  creek.  At  its  point  of  connection  with  the  moraine  it  has  a  gently 
undulating  stirface,  but  about  a  mile  west  from  the  moraine  the  surface 
becomes  plane.  The  gravel  is  built  up  nearly  to  the  height  of  the  border- 
ing till  plain,  and  stands  60  to  70  feet  above  the  present  stream. 

The  headwater  portion  of  the  Kankakee  River  leads  through  a  gravel 
plain  which  descends  toward  the  river  from  moraines  on  either  side.  On 
the  north  side  the  gravel  plain  comiects  with  the  Valparaiso  morainic  sys- 
tem, while  on  the  southeast  it  connects  with  the  Maxinkuckee  moraine  of 
the  Saginaw  lobe.  In  the  vicinity  of  Laporte,  Indiana,  the  gravel  plain 
which  is  connected  with  the  Valparaiso  morainic  system  attains  an  elevation 
of  fully  800  feet  above  tide  on  the  immediate  borders  of  the  moraine.  This 
great  altitude,  however,  is  apparently  maintained  for  only  a  short  distance, 
for  the  railway  surveys  show  that  there  is  a  descent  in  it  along  the  border 
of  the  moraine,  both  toward  the  northeast  and  the  southwest,  as  well  as  a 
descent  in  passing  southeastward  from  the  moraixie  to  the  Kankakee  River. 
The  elevation  of  the  gravel  plain  at  New  Carlisle  on  the  borders  of  the 
moraine  is  but  770  feet,  while  at  Laporte  it  is  about  810  feet.  At  Stillwell, 
7  miles  southeast  of  Laporte,  in  a  course  directly  away  from  the  moraine, 
the  altitude  is  only  730  feet,  while  at  Wellsboro,  directly  south  of  La- 
porte and  only  3  or  4  miles  from  the  moraine,  the  altitude  is  760  feet. 
Passing  southwestward  from  Wellsboro,  parallel  with  the  outer  border  of 
the  moraine,  the  altitude  decreases  to  730  feet  at  Wanatah. 

The  moraine  is  bordered  by  a  gravel  plain  no  farther  west  than  eastern 
Porter  County.     In  western  Porter  County  the  moraine  extends  down  to 


THE  VALPARAISO  MOEAINIO  SYSTEM.  379 

the  border  of  the  Kankakee  marsh  and  borders  this  marsh  somewhat  closely 
across  Lake  County,  Indiana.  Whatever  outwash  there  may  have  been 
along  the  border  of  the  moraine  in  western  Porter  and  in  Lake  County,  has 
been  removed  by  currents  of  water  passing  down  the  Kankakee. 

Numerous  references  have  been  made  to  the  gravel  outwash  on  the 
east  border  of  the  Valparaiso  morainic  system  in  southwestern  Michigan, 
and  the  relation  of  this  outwash  to  the  Valparaiso  morainic  system  has  been 
set  forth  in  the  discussion  of  the  border  between  the  Lake  Michigan  and 
Saginaw  lobes.  The  line  of  escape  for  the  small  bodies  of  water  in  which 
this  outwash  was  formed  have  been  only  partially  worked  out.  It  seems 
highly  probable  that  the  escape  was  southward  into  the  Kanlcakee  from  the 
Dowagiac  Valley,  and  possibly  this  line  was  open  for  waters  collected  in  the 
headwater  portion  of  the  Pawpaw  drainage  basin.  Drainage  may  have 
been  greatly  obstructed  at  times  by  the  Saginaw  lobe,  and  the  height  to 
which  water  rose  was  probably  greatly  influenced  by  the  oscillations  of  the 
ice  margin.  The  great  amount  of  sandy  and  gravelly  material  formed 
along  the  elevated  eastern  border  of  the  Valparaiso  morainic  system  appar- 
ently indicates  the  action  of  water  at  heights  of  300  feet  or  more  above  the 
level  of  Lake  Michigan,  or  about  900  feet  above  tide.  If  this  height  were 
attained  by  the  waters  held  between  the  Saginaw  and  Lake  Michigan  ice 
lobes  in  Allegan  and  Van  Buren  counties,  they  might  easily  find  escape 
southward  to  the  Kankakee  Basin  whenever  the  ice  lobes  afforded  an  oppor- 
tunity for  escape,  for  the  head  of  the  Kankakee  Basin  stands  only  a  little 
more  than  700  feet  above  tide.  There  does  not  appear  to  have  been  a  uni- 
form filling  along  the  line  of  the  supposed  southward  discharge.  On  the 
contrary  the  gravel  plains  appear  to  be  rather  in  the  form  of  small  deltas 
extending  out  for  a  few  miles  where  the  slopes  favored  drainage,  but  absent 
along  the  portion  of  the  morainic  border  where  the  slopes  are  unfavorable 
to  such  drainage.  The  gravel  outwash  appears  to  be  nearly  constant  along 
the  Dowagiac  Valley  throughout  its  entire  length,  a  feature  which  seems  to 
favor  strongly  the  view  that  southward  discharge  was  seldom  interrupted, 
but  on  the  Pawpaw  and  Kalamazoo  tributaries,  as  already  noted,  the  out- 
wash  is  more  restiicted. 

Upon  the  whole  the  Valparaiso  morainic  system  displays  a  coarser  out- 
wash  and  gives  evidence  of  more  vigorous  drainage  than  has  been  found  on 
any  of  the  morainic  systems  of  the  early  Wisconsin  series,  though  it  is 
closely  rivaled  by  the  drainage  from  the  Bloomington  system. 


380  THE  ILLINOIS  GLACIAL  yLOBE. 

SECTION  Y.    THE  liAKE-BORDEK  MORAINIC  SYSTEM. 

Between  the  Valparaiso  moraiuic  system  and  the  shore  of  Lake  Michi- 
gan there  is  a  series  of  till  ridges  running  nearly  parallel  with  the  lake  shore. 
In  the  Illinois  portion  three  ridges  are  developed  in  Lake  and  northern 
Cook  County,  but  in  Lake  County,  Indiana,  at  the  head  of  the  lake,  these 
ridges  are  wanting.  On  the  southeast  border  of  the  lake  two  of  them  reap- 
pear and  a  third  one  sets  in  north  of  the  mouth  of  the  Kalamazoo  River. 
Though  usually  distinct,  the  ridges  are  in  places  coalesced,  as  described 
below.  The  gap  at  the  head  of  the  lake  is  so  wide  that  strict  correlation 
between  each  ridge  on  opposite  sides  of  the  gap  can  scarcely  be  made,  but 
there  is  little  room  for  questioning  the  interpretation  that  the  ridges  on  the 
southeast  border  belong  to  the  same  morainic  system  as  those  on  the  west 
side  of  the  lake.  They  not  only  have  the  same  position  with  reference  to 
the  Valparaiso  morainic  system,  but  also  are  strikingly  similar  in  topography 
and  structure.  It  is  found  convenient  to  take  up  the  discussion  of  the  ridges 
of  each  district  separately.  Those  west  of  the  lake,  in  Lake  and  Cook  coun- 
ties, Illinois,  are  first  discussed,  and  then  those  on  the  southeast  border. 

TILL  RIDGES  OF  LAKE  AND   COOK  COUNTIES,   ILLINOIS. 
THE    OUTER    OR    WEST    RIDGE. 

The  outer  or  west  ridge  enters  Illinois  from  Wisconsin  on  the  west 
side  of  the  Des  Plaines  River,  its  outer  border  being  for  a  few  miles  followed 
by  Mill  Creek,  while  its  inner  extends  to  the  west  bluif  of  the  Des  Plaines 
River.  Just  below  Gurnee  the  river  passes  through  a  gap  in  the  ridge,  and 
for  several  miles  south  follows  closely  the  outer  border.  The  river  then 
bears  away  a  short  distance,  and  the  outer  border  of  the  ridge  for  the 
remainder  of  its  course  lies  a  mile  or  more  east  of  the  stream.  In  Lake 
County  the  ridge  is  sufficiently  prominent  and  bulky  to  constitute  a  marked 
feature,  and  has  a  general  width  of  about  2  miles.  In  the  soutli  part  of  the 
county  it  sends  out  a  weak  spur  to  join  the  middle  ridg'e  near  Deerfield, 
while  the  main  ridge  continues  south  into  Cook  County,  gradually  decreas- 
ing in  strength  and  dying  out  in  a  plain  near  j\Iont  Clare,  in  the  southwest- 
ern part  of  Jefferson  Township  (T.  40,  R.  12  E.).  For  5  or  6  miles  north 
from  its  soutlaern  terminus  it  rises  scarcely  10  feet  above  tlie  bordering 


THE  LAKE-BOEDER  MOEAIJflC  SYSTEM.  381 

plains,  and  is  distinguishable  from  them  mainly  in  being  more  midulatory. 
Where  well  developed,  as  in  northern  Lake  County,  the  moraine  has  numer- 
ous knolls,  20  to  25  feet  in  height,  and  these  stand  upon  a  basement  ridge 
whose  relief  is  nearly  25  feet.  A  noticeable  feature  of  this  and  also  of  the 
other  ridges  of  this  system  is  the  difference  in  the  breadth  of  the  outer  and 
inner  slopes,  the  usual  breadth  of  the  outer  slope  'being  scarcely  one-half 
that  of  the  inner. 

THE    MIDDLE    RIDGE. 

As  already  noted,  this  ridge  is  joined  to  a  spur  from  the  west  ridge  south 
from  Deerfield.  The  combined  belt  finds  its  southern  terminus  near  the 
head  of  the  Chicago  River  and  at  the  border  of  the  Glacial  Lake  Chicago. 
A  possible  continuation  southward  is  discussed  below.  The  course  of  the 
belt  is  south  to  noi'th,  through  Northfield  Township,  Cook  County.  Upon 
entering  Lake  County  it  becomes  distinct  from  the  spur  and  remains  a 
distinct  ridge  for  a  distance  of  15  miles.  It  there,  in  sec.  18,  Waukegan 
Township  (T.  46,  R.  12  E.),  becomes  united  with  the  east  lidge  and  remains 
united  with  it  as  far  north  as  it  has  been  examined.  On  each  side  of  this 
ridge  there  is  a  narrow  sag  or  slough.  The  sag  on  the  east  is  marshy  its 
entire  length  from  Winnetka,  in  Cook  County,  northward  to  the  latitude  of 
Waukegan,  a  distance  of  nearly  20  miles.  For  a  couple  of  miles  at  its 
southern  end  it  has  a  width  of  one-half  mile  or  more,  but  the  usual  width 
is  only  one-fourth  mile.  The  sag  on  the  western  or  outer  border  contains 
a  marsh  from  Rondout  Station  southwai'd  to  the  Lake  and  Cook  County 
line,  a  distance  of  about  9  miles. 

This  I'idge,  like  the  west  ridge,  has  low  knolls  along  its  crest,  8  to  16 
feet  in  height,  but  the  coalesced  ridge  in  northern  Cook  County  is  more 
billowy  and  carries  knolls  20  feet  oi-  more  in  height.  There  are  basins  and 
winding  sloughs  among  the  knolls,  which  add  to  the  morainic  expression. 

THE    EAST    RIDGE. 

The  southern  terminus  of  the  east  ridge  is  at  Winnetka,  where  Lake 
Michigan  cuts  it  off.  It  has  apparently  had  its  entire  east  slope  and  a 
portion  of  the  crest  removed  by  the  lake,  there  being  a  descent  immediately 
from  the  bluff  on  the  lake  to  the  slough,  which  lies  west  of  the  ridge. 
Following  the  ridge  north  to  Highland  Park  the  crest  and  east  slope  appear. 


382  THE  ILLINOIS  GLACIAL  LOBE. 

Continuing  noi'tli  to  Lake  Forest,  a  naiTow  till  plain  appears  on  the  east  of 
the  ridge,  the  inner  border  of  the  ridge  Ij'ing  back  a  half  mile  or  more 
from  the  lake  front.  Still  farther  north,  at  Wankegan,  the  inner  border  lies 
back  about  2  miles  from  the  lake  front.  The  usual  width  of  this  ridge 
is  about  1  mile.  The  crest  of  the  ridge  usually  stands  110  to  125  feet  above 
the  lake.  At  Winnetka,  the  higher  portion  being  removed,  it  rises  but  80 
feet  above  the  lake.  The  till  plain  east  of  the  ridge  stands  75  feet  or  more 
above  the  lake. 

In  this  connection  it  may  be  remarked  that  the  rate  at  which  the  lake 
bluff  is  being  encroached  upon  by  wave  action  has  become  a  matter  of 
much  concern  to  the  residents.  It  is  estimated  by  early  settlers  that  from 
Wankegan  to  Evanston  there  has  been,  during  the  thirty  years  from  1860 
to  1890,  a  strip  about  150  feet  in  width  undermined  and  carried  into  the 
lake.  This  amounts  to  about  500  acres,  representing,  at  present  valuation, 
nearly  81,000,000  worth  of  property. 

PROBABLE    CONTINUATIONS. 

None  of  these  ridges  have  been  found  to  have  connection  at  their 
southern  end  with  the  massive  Valparaiso  morainic  system,  nor  do  they 
admit  of  continuous  tracing  around  the  southern  end  of  the  lake  within 
(north  of)  that  moraine.  The  weak  development  in  that  district  seems  the 
more  remarkable  since  there  is  on  the  east  side  of  Lake  Michigan,  north- 
ward from  Porter  County,  Indiana,  a  series  of  ridges  of  similar  size  and 
complexity  to  that  under  discussion  and  which  are  probably  its  continua- 
tion. The  conditions  which  affected  the  southern  end  of  the  ice  lobe  at  the 
time  these  belts  were  forming  are  so  poorly  known  that  it  may  be  difficult 
to  ascertain  what  caused  this  wide  gap.  The  question  naturally  arises 
whether  the  expanded  lake  and  its  old  outlet  may  not  have  removed  the 
ridges. 

In  the  case  of  the  western  ridge  this  suggestion  seems  inapplicable, 
since  the  terminus  at  Mont  Clare  is  outside  the  well-defined  beaches  and 
above  their  level.  The  ice  sheet  here,  however,  may  have  terminated  in 
water  held  between  its  front  and  the  inner  slope  of  the  Valparaiso  morainic 
system  in  the  brief  period  required  for  the  cutting  down  of  the  outlet  to  the 
level  of  the  upper  beach.  But  in  that  case,  while  wave  action  may  have 
removed  weak  morainic  features,  it  seems  scarcely  probable  that  there  could 


THE  LAKE-BORDER  MORAINIC  SYSTEM.  383 

have  been  a  complete  obliteration  of  so  strong  a  belt  as  is  present  in  districts 
to  the  north.  In  the  case  of  Middle  and  East  ridg-es,  as  shown  below,  there 
may  have  been  some  erosion  by  the  lake  outlet  and  lake  waves. 

Middle  Ridge  has  its  sonthem  terminus  as  a  well-defined  ridge  at 
the  point  where  it  meets  the  upper  or  Glenwood  beach  of  Lake  Chicago 
There  is,  however,  near  the  southwestern  limit  of  the  city  of  Chicago,  a  till 
ridge  known  as  "Blue  Island,"  and  connected  with  it  a  bowlder  belt,  each 
of  which  may  be  correlatives  of  this  morainic  ridge.  This  ridg-e  leads  north 
to  south  for  a  distance  of  about  6  miles  along  the  line  of  Calumet  and 
Worth  townships,  and  Blue  Island  village  is  situated  at  its  southern  end. 
At  that  end  the  ridge  stands  about  60  feet  above  Lake  Michigan,  but  rises 
northward  to  an  altitude  85  or  90  feet  above  the  lake.  Its  width,  including 
the  slopes,  is  only  about  1  mile.  The  northern  portion  is  gently  undulating 
and  is  strewn  with  bowlders,  but  the  remainder  of  the  ridge  is  smooth  and 
comparatively  free  from  surface  bowlders.  Around  this  ridge  there  are 
shore  marks  in  the  form  of  eroded  banks  and  gravelly  beaches  at  an  alti- 
tude 55  to  60  feet  above  the  present  lake  level.  On  its  west  border  sand 
from  the  old  lake  shore  is  drifted  into  dunes  that  extend  nearly  to  the  top 
of  the  ridge.  Blue  Island  Ridge  owes  its  elevation  to  a  thickening  of  the 
drift  deposits  and  not  to  a  rock  nucleus,  for  the  rock  surface  is  as  low  beneath 
it  as  on  border  plains.  A  well  at  Morgan  Park,  near  the  crest,  reaches  a 
level  70  feet  below  the  base  of  the  ridge  before  entering  limestone. 

A  train  of  bowlders  is  traceable  north  from  the  north  end  of  "Blue 
Island"  through  the  western  part  of  the  city  of  Chicago  to  the  vicinity  of 
the  Chicago  River  in  Jefferson  Township.  Although  portions  of  the  line 
fall  within  a  part  of  the  city  where  dwellings  are  numerous,  the  bowlders 
still  remain  in  sufficient  numbers  to  be  a  noticeable  feature.  In  the  thinly 
settled  part  of  the  city  from  South  Lynne  southward  to  Blue  Island  they 
remain  in  about  their  natural  abundance.  The  belt  occupied  by  the  bowl- 
ders is  a  mile  or  more  in  width.  There  appear  to  have  been  several  hundred 
surface  bowlders  to  the  square  mile  along  this  line,  while  on  bordering  dis- 
tricts there  are  estimated  to  have  been  scarcely  100  to  the  square  mile. 
From  the  north  end  of  this  bowldery  tract  to  the  south  end  of  Middle 
Ridge  the  interval  is  but  a  few  miles,  and  is  mainly  covered  by  deposits 
of  lake  sand  and  gravel  which  would  obscure  any  bowlder  connection 


384  THE  ILLINOIS  GLACIAL  LOBE. 

which  may  have  existed.  There  seems,  therefore,  nothing  to  oppose  the 
correlation  of  the  bowlder  train  and  Bine  Island  Ridge  with  Middle  Ridge. 

From  the  sonth  end  of  Blue  Island  Ridge  to  the  till  ridges  in  Porter 
County,  Indiana,  no  line  of  bowlders  or  indication  of  the  position  of  the 
ice  margin  has  been  found.  Sucli  features  as  bowlders  may,  however,  be 
concealed  in  much  of  that  district  by  the  heavy  deposits  of  lake  sand. 

East  Ridge  apparently  had  some  continuation  southward  beneath  the 
present  lake.  Prof.  L.  E.  Cooley,  of  the  Chicago  Drainage  Commission, 
states^  that  in  a  series  of  dredgings  in  the  soutli  end  of  the  lake,  made  a 
few  years  since,  under  his  direction,  a  bowldery  belt  was  traced  for  several 
miles  southeastward  from  Winnetka,  the  present  terminus  of  East  Ridge. 
This  bowldery  belt  is  probably  a  residue  from  a  ridge  of  till  which  has  been 
cut  away  by  the  lake. 

RELIEF. 

West  Ridge  rises  with  a  somewhat  abrupt  slope  about  25  feet  above 
the  plain  along  the  Des  Plaines  River.  On  the  inner  (eastern)  side  there  is 
a  gradual  descent  of  about  40  feet  to  the  plain  along  the  Chicago  River, 
and  of  20  to  25  feet  to  the  marshy  plain  in  Lake  Count)-. 

Middle  Ridge  has  a  relief  of  20  to  26  feet  above  the  marsh}-  plain  on 
its  outer  border,  and  a  gradual  slope  of  25  to  40  feet  to  the  sag  or  slough, 
which  lies  on  its  inner  border. 

East  Ridge  has  a  relief  of  20  feet  in  northern  Lake  County  and  35  to 
40  feet  in  southern  Lake  and  northern  Cook  counties  above  the  sag  on  its 
outer  border.  The  reliefs  of  all  these  ridges  are  lessened  at  the  northern 
end  because  of  increase  of  elevation  in  the  sags  or  plains  which  separate 
them.  The  ridges  each  maintain  a  nearly  uniform  height  of  about  100  feet 
above  Lake  Michigan  throughout  their  course  in  Illinois. 

THICKNESS   OF   DKIFT. 

In  numerous  borings,  75  to  100  feet  in  depth,  no  rock  is  struck  and  no 
outcrops  of  rock  occur  along  this  portion  of  the  lake  shore.  The  drift 
beneath  the  level  of  the  base  of  these  moraines  was  probably  deposited  by 
earlier  ice  advances.  The  following  list  of  borings  which  have  struck  rock 
indicates  that  in  several  places  at  least  the'  rock  surface  lies  much  below 
the  surface  of  Lake  Michigan. 

1  Commuoication  to  tbo  writer. 


THE  LAKE  BOEDER  MOEAINIO  SYSTEM.  385 

x\t  Senator  C.  B.  Farwell's  artesian  well,  in  Lake  Forest,  rock  is  struck 
at  160  feet.  The  well  mouth  is  40  to  45  feet  below  the  crest  of  East  Ridg-e 
at  Lake  Forest  and  about  75  feet  above  Lake  Michigan. 

At  Highland  Park  rock  is  struck  at  160  to  175  feet.  The  elevation 
above  the  lake  is  100  to  115  feet. 

At  Lloyd's  artesian  well,  in  the  north  part  of  Wiunetka,  rock  is  struck 
at  150  feet.  The  well  mouth  is  by  surveyors'  level  78  feet  above  Lake 
Michigan. 

At  Ravenna  a  well  strikes  rock  at  164  feet.  The  surface  level  has  not 
been  accurately  determined,  but  it  is  probabh"  about  100  feet  above  Lake 
Michigan. 

Near  Schermerville  rock  is  struck  at  147  feet.  The  surface  elevation 
does  not  exceed  100  feet  above  Lake  Michigan. 

On  the  crest  of  West  Ridge,  in  sec.  14,  Maine  Township  (T.  41,  R. 
12  E.),  rock  is  struck  at  110  feet.  The  elevation  is  probably  about  the 
same  amount  above  the  lake. 

STRUCTURE    OF    THE    DRIFT. 

Along  the  lake  shore  the  bluffs  from  Winnetka  to  the  vicinity  of  Wau-- 
kegan  rise  abruptly  75  to  90  feet  and  present  many  good  exposures  of  the 
drift  to  this  depth.  There  is  at  the  surface  a  pebbly  yellow  clay  8  to  13 
feet  in  depth,  which  is  similar  to  that  in  the  other  moraines.  Beneath  this 
clay  is  a  grayish  blue  till  containing  occasional  sand  pockets  saturated  with 
water.  These,  however,  form  but  a  small  part  of  the  drift.  The  bulk  of 
the  bluff  is  a  compact  till,  but  moderately  pebbly  and  exposing  only  an 
occasional  embedded  bowlder.  It  was  noted  that  the  pebbles  and  bowlders 
are  usuall)''  striated. 

Neither  East  Ridge  nor  West  Ridge  nor  the  northern  portion  of  Mid- 
dle Ridge  has  gravelly  knolls  of  any  consequence,  but  the  southern  portion 
of  Middle  Ridge,  lying  in  Cook  County,  has  many  such  knolls.  Indeed, 
nearly  every  prominent  knoll  contains  gravel.  It  seldom  exceeds  15  feet 
in  depth  and  appears  to  be  confined  to  the  knolls,  for  they  are  situated  on 
a  basement  ridge  of  till  similar  to  the  till  exposed  along  the  lake  bluff. 

But  one  complete  reliable  section  of  the  drift  could  be  obtained,  which, 
though  valuable,  needs  to  be  supplemented  b}^  other  records  to  furnish  a 
MON  xxxviii 25 


3S6  THE  ILLINOIS  GLACIAL  LOBE. 

satisfactory  knowledge  of  the  lower  portion  of  the  drift.  The  well  is 
located  at  Ravinia.  Its  section  was  furnished  by  the  driller,  William 
McWendle,  of  Oak  Glen. 

Section  at  Ravinia,  Lake  County,  Illinois. 

Feet. 

1.  Pebbly  yellow  clay 11 

2.  Grayish-blue  pebbly  clay 60 

3.  Gray  clay,  very  pebbly 10-12 

4.  Grayish-blue  pebbly  clay,  lighter  color  than  No.  2 70 

5.  Clay,  resembliug  putty 1-5 

6.  Limestone - 22 

Total  drift 164 


TILL  RIDGES   ON  THE   SOUTHEAST  BORDER  OF  LAKE  MICHIGAN. 

THE    OUTER   RIDGE. 

The  outer  ridge  is  distinctly  traceable  only  from  the  vicinity  of  Benton 
Harbor,  Michigan,  to  "Wheeler,  in  Porter  Count}',  Indiana.  It  is  closely 
associated  with  the  Valparaiso  morainic  system  for  a  few  miles  north  from 
Benton  Harbor,  but  a  ridge  supposed  to  be  its  continuation  is  found  west 
of  the  "Pine  Plains"  in  Geneva  Township,  Van  Buren  County,  and  Casco 
Township,  Allegan  County.  Farther  north  it  has  not  been  recognized  and 
may  be  combined  with  Covert  Ridge.  It  is  separated  usually  from  the 
inner  border  of  the  Valparaiso  system  by  a  narrow  plain  averaging  scarcely 
more  than  2  miles  in  width  and  nowhere  exceeding  5  miles. 

From  the  point  of  connection  with  the  Valparaiso  system,  east  of 
Benton  Harbor,  in  Berrien  County,  Michigan,  southwestward  to  the  St. 
Joseph  River,  a  distance  of  4  or  6  miles,  there  is  only  a  vaguely  defined 
morainic  belt.  But  immediately  south  of  St.  Joseph  River,  about  3  miles 
south  of  Benton  Harbor,  a  definite  ridge  sets  in,  which  leads  southward 
along  the  east  side  of  the  Vandalia  Railway  to  -within  a  mile  of  Baroda. 
A  gap  about  a  mile  in  widtli  here  occurs,  through  which  Hickory  Creek 
finds  a  passage  and  which  is  also  utilized  by  the  railway.  Tlie  ridge  sets 
in  on  the  west  side  of  the  creek,  in  sec.  10,  T.  6  S.,  R.  19  W.,  and  leads  in 
a  slightly  winding  course  west  of  south  to  New  Troy.  At  this  village  a 
narrow  gap  occurs,  through  which  tlie  North  Galien  River  has  a  passage. 
From  the  south  I)lufi'  of  this  stream  the  ridge  leads  soutliwestward  past 
Three  Oaks  and  comes  to  South  Galien  River  about  a  mile  north  of  tlie 


THE  LAKE-BOEDEE  MOEAINIC  SYSTEM.  387 

State  line.  But  here  there  is  a  very  narrow  gap  and  the  ridge  continues 
in  a  southwestward  course  across  northwestern  Laporte  County,  Indiana. 
The  ridge  is  very  weak  for  a  mile  or  more  about  5  miles  southwest  from 
where  it  crosses  the  State  line,  and  there  is  a  narrow  gap  at  Trail  Creek. 
From  Trail  Creek  westward  to  the  vicinity  of  Furness,  in  Porter  County, 
a  distance  of  about  12  miles,  the  ridge  is  double  and  the  members  are 
separated  by  a  marsh  a  mile  or  less  in  Avidth.  From  Furness  westward  to 
Bailey  the  ridge  presents  but  a  single  crest.  Near  Bailey  a  belt  of  promi- 
nent dunes  which  border  the  shore  of  Lake  Michigan  spreads  out  to  the 
south  in  such  a  way  as  to  make  it  difficult  to  trace  the  low  till  ridge.  It 
seems  probable,  however,  that  the  till  ridge  continues  but  little  beyond 
Bailey,  for  no  evidence  of  its  presence  could  be  found  in  railway  cuttings, 
which  are  quite  numerous  in  the  midst  of  the  belt  of  dunes. 

A  possible  continuation  of  this  ridge  is  found  toward  the  south  in  a 
narrow  till  ridge  which  leads  southward  from  a  point  near  Cln-isman  to  the 
Valparaiso  morainic  system  at  Wheeler.  This  would  involve  an  abrupt 
southward  turn  in  the  ice  margin  and  bring  it  to  the  inner  border  of  the 
Valparaiso  morainic  system. 

In  Lake  County,  Indiana,  no  sharply  outlined  till  ridge  has  been  found, 
but  a  low  ridge  with  undulatory  surface  leads  westward  from  Deep  River 
at  Hobart  along  the  north  side  of  Turkey  Creek,  a  distance  of  about  5  miles. 
It  is  separated  from  the  inner  border  of  the  Valparaiso  morainic  system  only 
by  a  narrow  plain,  scarcely  a  mile  in  average  width.  Possibly  this  marks 
the  continuation  of  the  ridge  under  discussion.  The  system  of  ridges  is  as 
obscure  in  western  Porter  and  Lake  counties,  Indiana,  as  in  southern  Cook 
County,  Illinois.  It,  tlierefore,  is  no  easy  matter  to  decide  upon  the  posi- 
tion of  the  ice  margin  in  these  counties  at  the  time  the  outer  ridge  was  in 
process  of  formation  in  counties  to  the  east. 

This  till  ridge  governs  drainage  to  a  marked  degree.  In  the  Indiana 
portion  South  Galien  River,  East  and  West  Trail  creeks,  and  Calumet  River 
all  have  their  courses  toward  Lake  Michigan  checked  and  courses  parallel 
with  the  lake  produced  by  its  presence.  In  Michigan  the  north  flowing  por- 
tion of  North  Qalien  River  is,  for  several  miles,  parallel  to  the  outer  border 
of  the  ridge.  The  relief  of  the  ridge  scarcely  reaches  50  feet  where  sharp- 
est, and  is  usually  but  20  or  30  feet.  The  plain  outside  rises  from  the  border 
of  the  ridge  toward  the  Valparaiso  moraine,  thus  leaving  along  the  outer 


388  THE  ILLINOIS  GLACIAL  LOBE. 

border  of  the  ridge  under  discussion  a  valley-like  depression  which  forms 
a  natural  line  for  drainage  between  the  gaps  through  which  the  sti-eams  pass 

The  width  of  this  ridge  averages  scarcely  1  mile  and  in  places  is  but 
one-half  mile.  It  has  usually  an  abrupt  outer  border  and  a  more  gradual 
slope  on  the  inner  border.  This  feature  is  maintained  where  the  ridg'e  has 
a  double  crest,  as  well  as  where  it  is  single. 

Although  the  ridge  usually  presents  a  well-defined  crest,  it  is  seldom 
sharply  morainic.  Indeed,  the  surface  is  nearly  as  smooth  as  on  portions 
of  the  bordering  plains.  The  highest  knolls  scarcely  exceed  15  feet,  and 
the  majority  are  but  5  to  10  feet  in  height.  For  a  few  miles  near  the  State 
Ime  the  crest  is  sharp.  It  is  also  sharp  in  Porter  County,  Indiana,  west 
from  Furness.     Usually  it  is  nearly  as  smooth  as  the  slopes. 

COVERT   RIDGE. 

Covert  Ridge  receives  its  name  from  the  village  of  Covert,  in  western 
Van  Buren  County,  Michigan,  which  stands  on  its  crest.  It  lies  between 
the  ridge  just  discussed  and  the  shore  of  Lake  Michigan,  and  is  usually  but 
1  to  4  miles  back  from  the  shore  of  the  lake.  In  places  it  comes  to  the  lake 
and  has  been  partiallv  eroded  by  the  lake  waves,  as  indicated  below. 

Covert  Ridge  connects  at  the  north  with  the  Valparaiso  morainic  svs- 
tem,  its  point  of  connection  being  in  Overisel  Township,  in  northern  Allegan 
County.  It  has,  however,  been  traced  a  few  miles  farther  north,  along  the 
inner  border  of  the  Valparaiso  system,  in  Zeeland  and  Jamestown  town- 
ships, Ottawa  County,  where  its  topography  and  structure  distinguish  it 
from  the  bordei'ing  Valparaiso  moraine.  No  attempt  has  been  made  to 
ti'ace  it  farther  north.  From  Overisel  Township  it  leads  southwestward 
through  the  village  of  East  Saiigatuck  to  the  Kalamazoo  River,  at  New 
Richmond.  The  river  makes  only  a  narrow  break  scarcely  more  than  a 
half  mile  in  width,  and  the  ridge  continues  southwestward  coming  to  the 
shore  of  Lake  Michigan,  near  the  line  of  Ganges  and  Casco  townships, 
Allegan  County,  exactly  opposite  the  State  line  of  Wisconsin  and  Illinois. 
In  the  middle  part  of  the  west  boundary  of  Casco  Township  the  lake  has 
cut  away  nearly  all  of  the  ridge,  leaving  only  a  strip  about  one-fourth  mile 
wide,  belonging  to  its  east  slope.  From  this  point  the  ridge  bears  nearly 
due  south  while  the  lake  border  beare  ^^•est  of  south,  and  at  South  Haven 
its  inner  border  is  nearly  a  mile  east  of  the  lake.     It  contiiaues  south  nearly 


THE  LAKE-BOEDER  MORAINIC  SYSTEM.  389 

to  Covert  and  reaches  a  distance  of  4  miles  from  the  lake  just  north  of  that 
village.  Its  course  then  changes  to  southwest  and  the  ridge  comes  to  the 
lake  border  near  the  middle  of  the  west  line  of  Hagar  Township,  Bemen 
Countjr  (T.  3  S.,  R.  18  W.).  From  this  point  it  follows  the  bluff  of  the  lake 
closely  to  the  mouth  of  the  St.  Joseph  River,  where  it  is  interrupted  for 
about  a  mile.  It  sets  in,  however,  in  the  cit}^  of  St.  Joseph  and  follows  the 
shore  of  the  lake  southward  for  about  8  miles  to  the  vicinity  of  Stevens- 
ville.  It  here  bears  inland,  passing  east  of  Bridgman  and  Sawyer,  but 
returns  to  the  lake  shore  again  at  Union  Pier,  and  is  nearly  removed  by 
the  lake  just  below  that  point.  The  Galien  River  Valley  interrupts  the  ridge 
for  a  space  of  about  a  mile,  but  the  ridge  reappears  on  its  south  bluff  in  sec. 
36,  T.  7  S.,  R.  21  W.,  and  from  this  point  is  continuously  developed  as  far 
south  as  the  State  line.  About  a  mile  south  of  the  State  line  it  becomes 
vague  and  is  represented  only  by  occasional  slight  ridging.  It  is  traceable, 
however,  as  far  southwest  as  the  valley  of  Trail  Creek  in  sec.  26,  T.  38, 
R.  4  W.,  about  4  miles  east  of  Michigan  City,  Indiana.  Possibly  it  finds 
its  continuation  westward  in  the  inner  member  of  the  double  ridg'e  which 
leads  from  Trail  Creek  Valley  to  Furness,  Porter  County,  Indiana,  though 
it  seems  quite  as  probable  that  it  had  its  continuation  nearer  the  lake  shore, 
and  has  been  either  removed  by  lake  waves  or  concealed  by  the  dunes, 
there  being  beach  lines  closely  associated  with  its  western  end  in  the  vicinity 
of  the  valley  of  Trail  Creek. 

Throughout  its  entire  length  of  about  80  miles  this  ridge  maintains  a 
nearly  imiform  width  of  about  1  mile,  the  only  notable  exception  being 
a  strip  a  few  miles  in  length  in  western  Allegan  County,  where  it  reaches  a 
width  of  2  or  3  miles.  Like  the  outer  ridge  it  jDresents  usually  a  more 
abrupt  slope  on  its  eastern  or  outer  border  than  on  its  inner  border. 

The  surface  of  this  ridge,  like  the  outer  ridge,  carries  only  gentle 
swells  and  shallow  saucer-like  dejDressions  except  at  the  north  where  it 
assumes  a  sharper  morainic  expression.  The  change  in  expression  sets  in 
abruptljT-  in  northeastern  Ganges  Township,  Allegan  County,  in  the  vicinity 
of  Hutchinson  Lake.  From  this  point  northeastward  knolls  16  or  20  feet 
in  height  are  common  and  occasionally  knolls  reach  a  height  of  40  feet. 
There  are  also  deep  basins,  the  most  conspicuous  of  which  is  the  one 
occupied  by  Hutchinson  Lake,  which  has  an  area  of  nearly  a  square  mile 
and  is  bordered  by  knolls  and  ridges  rising  40  or  50  feet  above  its  surface. 


390  THE  ILLINOIS  GLACIAL  LOBE. 

From  East  Saugatuck  northeastward  the  surface  is  billowy  without  well- 
defined  basins,  and  this  topography  is  maintained  for  some  distance  beyond 
the  point  of  connection  with  the  Valparaiso  morainic  system,  as  far  as  the 
examinations  have  been  carried. 

This  ridge,  like  the  outer  ridge,  has  had  considerable  influence  on  the 
course  of  drainage.  The  north  branch  of  Black  River  follows  nearly  its 
outer  border  from  Hutchinson  Lake  southward  to  the  vicinity  of  South 
Haven,  while  the  south  branch  follows  nearly  the  outer  border  from  Covert 
northward  to  the  same  point,  and  the  united  streams  there  pass  westward 
through  a  gap  in  the  ridge  to  the  lake.  Pawpaw  River  follows  the  outer 
border  of  the  ridge  for  about  8  miles  in  its  lower  course.  Hickory  Creek 
flows  northward  along  its  outer  border  for  about  6  miles  before  entering  the 
St.  Joseph  River.  North  Galien  River  follows  the  outer  border  for  about 
8  miles  below  the  village  of  New  Troy,  where  it  is  joined  by  South  Galien, 
and  the  luiited  stream  passes  westward  through  a  gap  in  the  ridge. 


ZEELAND    RIDGE. 


During  the  summer  of  1897  the  writer  discovered  a  till  ridge  in  north- 
western Allegan  aiad  southern  Ottawa  counties,  Michigan,  which  lies  west 
of  Covert  Ridge  and  which  extends  no  farther  south  than  the  vicinity  of 
the  mouth  of  the  Kalamazoo  River,  its  further  continuation  having  been 
cut  away  by  Lake  Michigan.  This  ridge  is  well  developed  immediately 
northeast  of  the  village  of  Zeeland  and  it  seems  appropriate  to  apply  to  it 
the  name  Zeeland.  The  portion  south  of  Holland,  however,  has  been 
known  by  the  residents  as  "May  Hill."  The  writer  has  examined  it  only 
from  the  meridian  of  Holland  northeastward  to  Grand  River,  north  of 
Hudsonville,  Ottawa  County,  a  distance  of  about  20  miles. 

The  ridge  stands  100  to  120  feet  above  Lake  Michigan,  where  best 
developed,  and  has  a  width  of  scarcely  1  mile.  It  is  interrupted  by  occa- 
sional gaps,  the  most  notable  being  the  one  tlu'ough  which  Black  River 
passes,  south  of  Zeeland,  which  is  about  1^  miles  in  width.^  From  a  point 
north  of  Vriesland  northeastward  to  Grand  River  it  lies  along  the  west 
border  of  a  large  abandoned  valley,  and  appears  to  have  been  partially 

'This  Black  River  should  be  distinguished  from  a  stream  of  the  same  nume  entering  Lake 
Michigan  at  South  Haven. 


THE  LAKE-BORDER  MORAINIG  SYSTEM.  39  [ 

removed  by  the  stream  which  formed  the  valley.  The  same  stream  also 
passed  through  the  gap  south  of  Zeelaud  aud  perhaps  has  widened  that  gap. 

This  ridge,  like  Covert  Ridge,  is  composed  of  a  clayey  till  strikingly 
in  contrast  with  the  more  porous  till  of  the  Valparaiso  system.  It  is  com- 
monly spoken  of  as  a  "clay  ridge,"  and  it  forms  the  southeast  border  of  an 
extensive  sand-covered  plain,  with  which  it  is  in  sharp  contrast. 

The  ridge  carries  only  gentle  swells  5  to  15  feet  in  height,  but  its  relief 
above  the  lower  tracts  on  either  side  is  sufficient  to  make  it  a  prominent 
feature.  It  rises  about  30  feet  above  the  general  level  of  the  sand-covered 
districts  which  border  it  on  the  west  and  about  an  equal  amount  above  a 
narrow  plain  on  the  east  which  separates  it  from  Covert  Ridge. 

The  extent  of  this  ridge  toward  the  north  remains  to  be  determined,  as 
no  investigation  has  been  made  north  of  Grand  River.  An  inspection  of 
railway  profiles  suggests  that  its  course  may  be  directly  north,  past  Coopers- 
ville  into  the  southeast  part  of  Muskegon  County.  The  relation  of  this 
ridge  to  certain  sand  deposits  found  on  its  eastern  border  is  discussed  on  a 
later  page. 

RELIEF. 

The  outer  ridge  and  Covert  Ridge  each  show  slight  relief  above  the 
districts  on  their  outer  border.  The  greatest  relief  scarcely  exceeds  50 
feet  and  the  usual  relief  is  but  25  or  30  feet.  The  abruptness  of  the  outer 
slope,  however,  in  each  of  the  ridges  renders  this  slight  relief  a  somewhat 
conspicuous  feature,  and  the  ridges  may  be  seen  distinctly  for  a  distance  of 
several  miles  when  viewed  from  their  outer  border.  On  the  inner  border 
the  descent  is  gradual  from  the  crest  of  each  ridge,  usually  amounting  to 
but  20  or  30  feet  per  mile. 

RANGE   IN   ALTITUDE. 

Each  of  the  ridges  show  comparatively  slight  range  in  altitude.  The 
lowest  parts  are  nearly  75  feet  above  Lake  Michigan  and  the  highest 
scarcely  150  feet.  Throughout  much  of  its  course  each  ridge  stands  about 
100  feet  above  the  lake.  The  crests  of  the  ridges  are  usually  but  40  or  50 
feet  above  the  level  of  the  highest  beach  of  Lake  Chicago,  and  in  places 
they  come  down  nearly  to  the  level  of  the  beach.  The  plains  bordering  the 
ridges  were  quite  extensively  submerged  by  the  lake  or  stood  so  little  above 
the  lake  level  as  to  be  poorly  drained  until  the  lake  level  had  been  lowered. 


392  THE  ILLI^fOIS  GLACIAL  LOBE, 

THICKNESS   OF   DRIFT. 

These  ridges  occupy  a  region  in  which  the  drift  deposits  are  very 
thick,  but  it  is  probable  that  the  drift  deposited  at  the  time  of  their  forma- 
tion is  mainly  confined  to  the  ridges,  with  only  a  thin  sheet  on  the  plain 
which  separates  them  and  the  plain  between  the  Covert  Ridge  and  the  lake. 
The  relief  of  the  ridges  probably  represents  approximately  the  thickness  of 
the  drift  deposited  at  this  stage.  The  following  list  of  borings  which  have 
stnick  rock  indicate  that  throughout  much  of  this  disti'ict  the  rock  surface 
lies  considerably  below  the  surface  of  Lake  ]\Iichigan: 

At  Hammond,  in  Lake  County,  Indiana,  the  distillery  well  penetrated 
110  feet  of  di-ift,  reaching  a  level  95  feet  below  the  smface  of  Lake 
Michigan  before  entering  rock. 

At  Owen's  brick  yards,  in  Hobart,  Indiana,  rock  was  entered  at  150 
feet,  at  a  level  100  feet  below  the  surface  of  Lake  Michigan. 

The  Blau-  artesian  well,  in  the  northeast  part  of  Porter  County,  entered 
rock  at  240  feet,  at  a  level  220  feet  below  the  surface  of  Lake  Michisran. 

At  the  northern  Indiana  penitentiary,  near  Michigan  City,  Indiana, 
rock  was  eiitered  at  172  feet,  at  a  level  156  feet  below  Lake  Michigan. 
A  gas  boring  in  Michigan  City  reached  a  level  230  feet  below  the  lake 
before  entering  rock. 

At  New  Buffalo,  Michigan,  a  boring  penetrated  212  feet  of  drift,  enter- 
ing rock  at  192  feet  below  the  level  of  Lake  Michigan.^ 

At  New  Troy,  Michigan,  a  well  is  reported  to  have  struck  rock  at  onlv 
65  feet,  or  at  a  level  but  20  feet  below  Lake  Michigan.  A  well  near  New 
Troy,  in  sec.  30,  T.  7  S.,  R.  19  W.,  is  reported  to  have  entered  shale  at  a 
depth  of  90  feet  and  a  level  about  20  feet  below  the  lake. 

At  Sawyer  Station,  ^lichigan,  Mr.  Rough  sunk  a  well  which  entered 
rock  at  a  depth  of  123  feet  and  a  level  56  feet  below  Lake  Michigan. 

At  Bridgman,  Michigan,  a  well  at  the  box  factory  entered  rock  at  140 
feet,  at  a  level  78  feet  below  Lake  Michigan. 

At  the  basket  factory  in  St.  Joseph,  Michigan,  rock  is  entered  at  about 
123  feet  below  Lake  Michigan  and  at  a  similar  level  in  a  well  at  the  Park 
Hotel.  The  gas  well  at  Benton  Harbor  entered  rock  at  124  feet  below  the 
level  of  the  lake. 

'  Geol.  of  Indiana,  1873,  p.  431. 


THE  LAKE-BORDER  MORAINIC  SYSTEM.  398 

At  South  Haven,  Michigan,  a  well  at  the  basket  factor}^  entered  rock 
at  105  feet  below  lake  level.  A  well  on  the  farm  of  J.  Irving  Pearce,  a  few 
miles  southeast  of  South  Haven  (in  sec.  31,  T.  1  S.,  R.  16  W.),  entered  rock 
at  130  feet  below  lake  level.  A  well  on  the  farm  of  W.  F.  Conner,  in 
sec.  34,  T.  2  S.,  R.  17  W.,  reached  a  depth  of  220  feet  and  a  level  125  feet 
below  Lake  Michigan  without  entering  rock. 

A  well  in  the  southeast  part  of  T.  1  N.,  R.  17  W.,  157  feet  in  depth, 
reached  a  level  nearly  100  feet  below  Lake  Michigan  without  entering  rock. 
Another  well  in  sec.  29,  T.  1  N.,  R.  16  W.,  140  feet  in  depth,  reached  a 
level  fully  100  feet  below  the  lake  without  entering  rock. 

At  D.  Kitchen's,  in  sec.  16,  T.  2  N.,  R.  16  W.,  a  well  reached  a  depth 
of  275  feet  and  a  level  165  feet  below  Lake  Michigan  without  entering  rock. 

A  well  IJ  miles  southeast  of  Pier  Cove,  Michigan,  142  feet  in  depth, 
reached  a  level  about  75  feet  below  the  lake  without  entering  rock. 

STRUCTURE    OF   THE   DRIFT. 

At  many  points  on  each  of  these  ridges  there  is  a  thin  coating  of  sand. 
It  is  usually  dx'ifted  into  low  knolls  and  ridges,  and  was  apparently  deposited 
in  large  part  by  wind.  Where  these  sand  deposits  are  8  or  10  feet  in  depth 
wells  along  the  ridges  often  pass  into  a  blue  till  at  the  base  of  the  sand,  but 
where  the  sand  deposits  are  thin  or  absent  a  yellow  till  several  feet  in  depth 
occurs  at  the  top  of  the  blue  till.  In  several  sections,  as  shown  below,  the 
yellow  till  was  found  to  have  a  thickness  of  but  3  or  4  feet.  The  usual 
thickness,  however,  is  nearly  twice  that  amount,  and  in  places  is  not  less 
than  20  feet.  The  ridge  on  the  north  side  of  the  Calumet  River,  in  Porter 
County,  Indiana,  furnishes  several  well  sections  in  which  the  thickness  of 
the  yellow  till  is  15  or  20  feet.  The  body  of  the  ridges  seems  to  be  com- 
posed of  blue  till  having  a  large  clayey  constituent,  and  on  the  whole  more 
compact  than  the  blue  till  found  in  the  Valparaiso  morainic  system.  The 
till  also  is  less  stony  as  a  rule  than  typical  till.  This  till  is  occasionally 
replaced  by  sand  or  gravel,  and  it  generally  contains  pockets  and  thin  beds 
of  sand  and  gravel  of  sufficient  extent  and  at  convenient  depths  to  supply 
the  shallow  wells.  There  are  places  where  a  nearly  pebbleless  laminated 
clay  replaces  the  till. 

Bowlders  are  found  in  moderate  number  along'  each  of  the  ridges. 
They  consist  largely  of  granite  rocks,  though  there  are  many  other  classes 
of  rocks  present.     As  is  usual  in  the  moraines  of  this  region,  the  surface 


394  THE  ILLINOIS  GLACIAL  LOBE. 

bowlders  are  composed  very  largely  of  pre-Cambrian  crystalline  rocks  of 
Canadian  derivation,  rocks  from  the  Paleozoic  formations  being  compara- 
tively rare.  But  the  till  contains  a  large  number  of  local  rocks,  and  its  rock 
constituents  vary  from  place  to  place,  following  in  a  general  way  the 
changes  in  the  underlying  rock  formations.  Large  bowlders  of  sandstone 
•were  found  on  Covert  Ridge  in  western  Allegan  County  similar  to  those 
noted  on  the  Valparaiso  moraine  in  Allegan  and  Van  Bin-en  counties.  A 
bowlder  of  red  jaspery  conglomerate,  apparently  from  the  Huronian  out- 
crops north  of  Georgian  Bay,  was  found  on  the  Covert  Ridge,  a  short 
distance  northeast  of  East  Saugatuck.  The  ice  inovement  which  formed 
the  ridge  can  scarcely  be  supposed  to  have  brought  the  bowlder  from  the 
parent  ledge,  for  the  line  of  axial  movement  was  southward  through  the 
Lake  Michigan  Basin,  and  the  radial  movementwas  southeastward  toward  this 
ridge.  The  presence  of  this  bowlder  is  probably  to  be  accounted  for  through 
an  earlier  ice  movement  which  crossed  Michigan  and  the  Lake  Michigan 
Basin  in  a  southwestward  course,  strewing  bowlders  along  its  path  to  be 
taken  up  by  the  later  movements  and  redeposited  in  the  later  till  sheets. 

An  excellent  section  of  the  structure  of  Covert  Ridge  is  fouiid  on 
the  shore  of  Lake  Michigan  a  few  miles  north  of  New  Buffalo,  in  sec.  25, 
T.  7  S.,  R.  21  W.  The  lake  bluff  here  is  about  95  feet  in  height.  At  the 
surface  there  is  a  coating  of  sand  in  places  6  or  8  feet  in  depth,  but  in  other 
places  only  a  few  inches.  Beneath  it  there  is  a  brownish-yellow  till  which 
graduates  into  blue-gray  till  within  8  or  10  feet  of  the  sm-face.  For  a 
depth  of  about  60  feet  the  till  shows  distinct  lamination  and  has  thin  part- 
ings of  sand  and  laminated  clay.  Below  this  depth  it  is  somewhat  harder 
and  the  lamination  is  very  imperfect.  It  is  probable  that  the  lower  30  feet 
of  the  exposure  is  independent  of  the  upper  60  feet.  The  latter  alone 
appears  to  be  referable  to  the  stage  of  glaciation  at  which  the  ridges  under 
discussion  were  formed.  About  one-half  mile  southwest  from  the  point 
just  described  the  lake  bluff  presents  the  following  series: 

Section  of  Covert  Ridge,  near  New  Buffalo,  Michigan. 

Feet. 
Beacli  gravels 8 

Brown  laminated  i-lay,  slightly  jiebbly,  -with  thin  partings  of  sand 1^ 

Blue  laiiiinateil  clay,  slightly  pebbly,  with  thin  partings  of  sand 14 

Coarse  water-hearing  sand 2 

Blue-gray  till,  very  stony,  interbedded  -witli  thin  layers  of  sand  in  horizontal  beds,  e.Ktending 
down  beneath  the  level  of  the  lake,  esjwsed 30 

Total 55i 


THE  LAKE-BOEDER  MORAINIO  SYSTEM.  395 

It  is  probable  that  the  upper  25  feet  of  this  section  is  a  deposit  made 
in  water,  and  possibly  also  the  lower  portion  was  deposited  under  similar 
conditions.  As  a  talus  obscures  the  lower  portion  of  the  bluff  in  places 
between  these  two  sections,  the  exact  equivalency  of  the  beds  at  the  base 
of  the  sections  can  not  be  established. 

North  of  St.  Joseph  there  are  exposures  along  the  shore  of  the  lake  in 
which  large  masses  of  cemented  gravel  and  sand  are  interbedded  with  the 
blue  till.  This  is  apparently  a  local  feature.  The  till  here,  as  in  the 
exposures  near  New  Buffalo,  shows  traces  of  lamination  and  is  scarcely  so 
pebbly  as  typical  till.  An  exposure  west  of  Hagar  StatioA,  at  a  point  where 
the  lake  bluff  is  cut  back  nearly  to  the  crest  of  Covert  Ridge,  shows  the 
following  series  of  beds: 

Section  near  Hagar,  Berrien  County,  Michigan. 

Teet. 

Sand,  varying  from  a  few  inches  to  several  feet 1-8 

Yellow  till,  thickest  where  sand  is  thin  1-5 

Blue  till,  not  very  stony 30 

Sand,  variable  in  coarseness,  with  thin  clay  beds 20 

Blue-gray  till,  quite  stony 50 

Total 110 

An  exposure  in  sec.  18,  T.  2  N.,  R.  17  W.,  shows  a  laminated  clay  at 
the  base  of  the  surface  sand  which  may  be  referable  to  the  glacial  lake, 
though  it  seems  more  probable  that  it  was  deposited  beneath  the  ice  sheet. 
The  section  of  the  lake  bluff  is  as  follows: 

Section  of  hluff  of  Lalce  Michigan  in  sec.  18,  T.  2  N.,  B.  17  W. 

Feet. 
Sand 4-8 

Laminated  gray  clay,  slightly  pebbly 12 

Sand  and  gravel 3 

Blue-gray  till,  quite  stony 15 

Total 36 

Several  sections  of  wells  were  obtained  in  each  of  the  counties  traversed 
by  these  ridges,  which  throw  light  upon  the  structure  of  the  drift  to  con- 
siderable depth.  In  a  few  cases  the  entire  drift  series  has  been  pene- 
trated. In  presenting  these  well  sections  the  discussion  begins  in  Porter 
County,  Indiana,  and  counties  are  taken  up  in  succession  toward  the 
northeast. 


396  THE  ILLINOIS  GLACIAL  LOBE. 

A  boring  on  the  till  ridge  north  of  Wheeler,  on  the  farm  of  Josephus 
Wolf,  157  feet  in  depth,  has  the  following  section: 

Section  of  ridge  north  of  Wheeler,  Indiana. 

Feet. 

Stony  yellow  till 15 

Blue  clay,  slightly  pebbly,  \yith  occasional  thin  sand  beds 140 

Gravel  bed 2 

Another  boring  on  the  same  farm  reached  a  depth  of  200  feet  without 
obtaining  water  or  entering  the  rock.  Usually  wells  in  that  vicinity  must 
penetrate  about  90  feet  of  compact  clay  before  entering  a  water-bearing 
bed,  but  in  a  few  places  sand  with  water  has  been  found  at  30  feet  or  less. 

Wells  on  the  till  ridge  north  of  the  Calumet  River,  in  eastern  Porter 
County,  have  reached  a  depth  of  150  feet  in  a  few  cases  without  entering 
rock.     One  at  Bailey,  148  feet  in  depth,  has  the  following-  section: 

Section  of  icell  at  Bailey,  Indiana. 

Feet. 

stony  yellow  till 18 

Dry  sand 40 

Blue  quicksand 40 

Blue  till 50 

Total 148 

A  well  immediately  north  of  Chesterton,  97  feet  in  depth,  has  the  fol- 
lowing section: 

Section  of  well  near  Chesterton,  Indiana. 

Feet. 

stony  yellow  till 20 

Soft  blue  clay,  with  few  pebbles 50 

Dry  sand ^ 15 

Sand  and  gravel,  with  water 12 

Total 97 

On  the  same  ridg'e,  a  mile  farther  east,  the  series  is  still  more  variable, 
as  follows: 

Section  of  ridge  north  of  the  Calumet  River,  near  Chesterton, 

Feet. 

stony  yellow  till 20 

Soft  blue  clay,  with  few  pebbles -10 

Dry  sand 12 

Hard  blue  till 5 

Sand  and  gravel,  with  water 11 

Total 88 

Near  the  line  of  Porter  and  Laporte  counties  the  wells  penetrate  only 
3  to  5  feet  of  yellow  till,  beneath  which  is  a  soft  l)lue  clav,  with  few  peb- 


THE  LAKE-BOEDER  MOEAINIO  SYSTEM.  397 

bles,  wliicli  extends  to  a  deptli  of  about  50  feet,  where  water-bearing  sand 
is  entered. 

At  the  Blair  artesian  well,  in  the  northeast  corner  of  Porter  County, 
240  feet  of  drift  was  penetrated  if  the  surface  sand  be  included.  The  well 
is  located  on  low  ground  near  the  lake,  only  15  or  20  feet  above  the  lake 
level.  The  rock  surface  is,  thei-efore,  nearly  225  feet  below  the  lake  level. 
The  following  notes  concerning  the  well  were  furnished  by  Mr.  John  Orr, 
of  Michigan  City: 

Section  of  Blair  artesian  loell  in  Porter  (Jaunty^  Indiana. 

Feet. 

1.  Surface  saud 18 

2.  Alternate  laj'ers  of  peaty  blue  clay  and  fine  sand 12 

3.  Soft  blue  clay,  slightly  pebbly,  with  thin  beds  of  gravel  included 55 

4.  Water-bearing  gravel  bed 2 

5.  Fine  sand 5 

6.  Water-bearing  gravel 2 

7.  Blue  clay  harder  than  "No.  3,"  apparently  a  typical  till 108 

8.  Water-bearing  gravel 5 

9.  Blue  clay  alternating  -with  beds  of  fine  sand 35 

10.  Thin  layer  of  shale ? 

11.  Gray  limestone 180 

12.  Soft  caving  rock,  probably  shale 30 

13.  Limestone 6 

14.  Soft  caving  rock,  probably  shale 30 

15.  Hard  limestone 370 

16.  Hard  blue  rock 2 

Total  depth 858 

A  flow  of  water  began  at  a  depth  of  68  feet  and  was  greatl}^  increased 
at  about  200  feet.  At  a  depth  of  370  feet  the  water  became  impregnated 
with  sulphureted  hydrogen  and  the  flow  was  increased.  The  rate  of  flow 
is  about  400  barrels  per  hour. 

In  Michigan  City  a  prospect  boring  for  natural  gas  obtained  only  a 
strong  flow  of  water.  The  first  flow  was  from  the  glacial  drift  at  a  depth 
of  210  feet.  Water  containing  sulphureted  hydrogen  was  struck  at  about 
450  feet.  The  section  (furnished  by  G.  C.  Marsh)  differs  somewhat  from 
that  at  the  Blair  well,  as  follows: 

Section  of  Coring  at  Michigan  City,  Indiana. 

Feet. 

Dry  surface  sand 15 

Quicksand 10 

Gravel 5 

Blue  clay,  slightly  pebbly '. 145 

Very  pebbly  blue  clay 22 

Cobble,  bowlders,  and  gravel 15 

Gravel  and  sand  with  an  occasional  bowlder 40 

Limestone  and  shale  as  in  previous  section. 


398  THE  ILLINOIS  GLACIAL  LOBE. 

The  following  section  of  a  well  at  the  northern  Indiana  penitentiary, 
near  Michigan  City,  ajDpeared  in  an  early  report  of  the  Indiana  geological 
survey.^  The  well  mouth  is  16  feet  above  Lake  Michigan  and  the  water 
will  rise  22  feet  above  the  surface.  The  well  has  an  estimated  discharge 
of  300  gallons  per  minute: 


o^ 


Section  of  well  at  northern  Indiana  penitentiary. 

Feet. 

Sand 48 

Clay 4 

Sand '. 24 

Blue  clay 66 

Sand '. 30 

Shale 76 

Upper  Silurian  limestone 293^ 

Total 541i 

The  following  section  was  observed  in  the  bluff  of  Trail  Creek  near  a 
mill  in  sec.  34.  T.  38  N.,  R.  4  W.: 

Section  of  bluff  of  Trail  Creel: 

Feet. 

1.  Brown  saud  with  thin  beds  of  pebbles 6 

2.  Brown  clay,  nearly  pebbleless,  mainly  noncalcareous,  but  with  thin  calcareous  bands 3 

3.  Brown  sand 1 

4.  Brown  clay,  similar  to  ' '  No.  2  " 1 

5.  Yellow  sand 6 

6.  Laminated  l>lue  clay  with  few  pebbles 10 

Total 27 

On  the  south  border  of  BeiTien  County,  Michigan,  in  sec.  19,  T.  8  S., 
R.  20  W.,  two  wells  85  feet  in  depth  are  mainly  through  a  soft  blue  till 
containing  but  few  pebbles.  In  that  vicinity  the  blue  till  is  often  found 
■n'ithin  4  feet  of  the  surface.  On  the  ridge  at  Three  Oaks  wells  usually 
penetrate  6  or  8  feet  of  yellow  till  before  entering  the  blue.  Soft  blue  till 
extends  to  a  depth  of  70  feet,  and  there  water-bearing  sand  is  usually 
struck. 

At  New  Buffalo,  Michigan,  the  blue  till  is  frequently  exposed  at  depths 
of  but  4  or  5  feet,  and  the  wells  in  the  higher  part  of  the  village  usually 
penetrate  about  60  feet  of  blue  till  before  striking  a  water-bearing  bed.  On 
low  gi'ound  near  the  shore  of  the  lake  flowing  wells  have  been  obtained  at  a 
depth  of  about  30  feet.     The  drift  at  New  Buffalo,  as  reportetl  in  an  early 

'  Geol.  of  Indiana,  1873,  pp.  47(M7I. 


THE  LAKE  BORDER  MORAINIC  SYSTEM.  399 

volume  of  the  Indiana  Survey,  has  a  depth  of  212  feet  at  the  Michigan 
Central  Station,  whose  altitude  is  only  20  feet  above  the  lake.^ 

At  Sawyer  a  deep  well  made  by  Mr.  Rough  has  the  following  section: 

Section  at  Sawyer,  Michigan. 

Teet. 
Surface  sand 3 

Blue  till,  wltli  sand  bed  at  25  feet  and  at  bottom 120 

Rock  of  bluish  color,  varyingin  hardness 208 

Total  deptb 331 

An  exposure  in  the  south  bluff  of  Galien  River,  at  New  Troy,  where 
the  till  ridge  is  undermined  by  the  stream,  shows  a  slightly  pebbly  blue 
clay  from  the  river's  edge  up  to  a  height  of  about  40  feet.  Above  this  clay 
there  is  a  brown  till  interbedded  with  calcareous  sand,  having  a  thickness 
of  12  feet.  A  well  in  the  village  of  New  Troy  raaj^  have  struck  rock  at  a 
depth  of  65  feet,  though  the  owner  of  the  well  thinks  that  sand  and  gravel 
was  entered  below  the  supposed  rock  ledge.  In  case  the  latter  interpreta- 
tion is  correct  the  former  is  probably  erroneous. 

At  the  point  where  the  Gralien  River  cuts  through  Covert  Ridge,  in 
sec.  2,  T.  8  S.,  R.  20  W.,  there  is  sand  at  the  top  of  the  bluff  12  feet  in 
depth,  below  which  is  a  brown  pebbly  clay  interbedded  with  sand  which  is' 
quite  calcareous.  Both  the  till  and  the  sand  are  in  beds  which  are  in  arch- 
ing and  oblique  attitudes.  On  the  north  bluff  of  the  river  nearly  opposite 
this  point  a  well  96  feet  in  depth  entered  blue  till  at  2  feet  and  continued 
in  it  to  the  bottom. 

At  Bridgman  a  boring  250  feet  in  depth  entered  rock  at  140  feet,  and 
struck  an  inflammable  gas  at  about  160  feet  which  would  burn  a  jet  several 
feet  in  height.  The  rock  is  apparently  a  shale.  The  upper  80  feet  of  the 
drift  is  mainly  blue  till,  but  the  lower  60  feet  is  gray  sand,  yielding  water. 

Along  the  St.  Joseph  River  there  are  extensive  exposures  of  blue-gray 
till  in  the  west  bluff  from  St.  Joseph  southward  to  the  mouth  of  Hickory 
Creek,  but  in  the  east  bluff  exj^osures  were  found  in  which  there  is  a  blue 
silt  free  from  pebbles  rising  to  a  height  of  30  feet  or  more  above  the  stream. 
This  silt  is  usually  capped  with  15  or  20  feet  of  sandy  ^-avel.  A  well  near 
the  east  bluff,  2J  miles  south  of  Benton  Harbor,  reached  a  depth  of  153 
feet  without  entering  rock,  and  is  mainly  in  blue  clay;  whether  silt  or  till 

'  Op.  cit.,  p.  431. 


400  THE  ILLINOIS  GLACIAL  LOBE. 

was  not  ascertained.  East  from  here,  in  the  vicinity  of  the  mouth  of  Pipe- 
stone Creek,  typical  till  is  found  in  the  east  bluff  of  the  river.  A  well  on 
this  bluff,  in  sec.  1,  T.  6  S.,  R.  18  W.,  138  feet  in  depth,  does  not  reach 
rock.  It  penetrated  about  30  feet  of  gravel,  beneath  which  it  was  mainly 
in  a  blue  till. 

At  St.  Josejih  a  well  at  the  Park  Hotel,  165  feet  in  depth,  enters  rock 
only  4  feet  and  obtains  a  water  that  is  slightly  lirackish.  The  upper 
■40  feet  is  mainly  in  blue  till,  biTt  the  remainder  of  the  drift  is  largely  a  fine 
sand  in  which  there  are  occasional  beds  of  clay  or  silt  cai'rying  fragments 
of  wood.  Wood  is  especially  abundant  at  about  140  feet.  Rock  was 
struck  at  the  basket  factory  in  St.  Joseph  at  about  the  same  level  as  in  the 
hotel  well,  and  a  slightly  brackish  water  was  obtained. 

An  experimental  gas  boring  at  Benton  Harbor,  on  low  ground  scarcely 
15  feet  above  lake  level,  penetrated  135  feet  of  drift  and  sand.  The  upper 
20  feet  was  entirely  sand.  Beneath  this  is  a  blue  clay  or  silt,  containing 
few  pebbles,  which  graduates  downward  into  a  gray  sand,  also  slightly 
pebbly,  and  this  sand  extends  to  the  rock. 

A  well  on  the  east  border  of  Covert  Ridge,  in  sec.  9,  Watervliet  Town- 
ship, reached  a  depth  of  125  feet  without  entering  rock.  It  was  tlu-ough 
till  with  the  exception  of  5  feet  of  sand  at  the  bottom.  Another  well  in 
the  same  section  entered  blue  till  at  4  feet,  which  continued  to  the  bottom 
of  the  well  at  52  feet.  Here  a  cemented  gravelly  crust  was  penetrated, 
beneath  which  water  was  obtained. 

A  boring  on  Covert  Ridge,  in  sec.  34,  Covert  Township,  at  W.  F. 
Conners,  reached  a  depth  of  220  feet  without  entering  rock.  It  was 
mainly  through  blue  till  and  no  water  was  obtained;  a  dug  well  only 
6  feet  from  it  found  water-bearing  gravel  at  36  to  38  feet. 

Two  wells  just  west  of  the  village  of  Covert,  in  sec.  15,  are  70  feet  in 
depth.  They  penetrate  15  feet  of  yellow  till,  beneath  which  is  a  blue  till 
extending  to  the  water-bearing  sand  at  the  bottom  of  the  wells.  A  well  in 
the  northeast  corner  of  sec.  22,  80  feet  in  depth,  is  in  till  from  top  to  bottom. 
A  well  on  the  west  side  of  sec.  22,  97  feet  in  depth,  penetrated  3  feet  of 
surface  sand,  beneath  which  it  was  entirely  in  till  to  a  water-bearing  sand 
at  bottom.  A  well  in  the  north  part  otf  sec.  14,  100  feet  in  deptli,  passed 
through  thin  beds  of  sand  which  occur  in  the  till  at  intervals  of  15  or  20 
feet.     A  well  near  the  center  of  sec.  11  has  a  depth  of  85  feet  and  is  in  till 


THE  LAKE-BORDER  MORAINIC  SYSTEM.  401 

from  the  top  down  to  a  quicksand  at  tbe  bottom.  A  well  in  the  SE.  ^  of 
sec.  2  has  a  depth  of  70  feet  and  is  in  till  with  the  exception  of  4  feet  of 
surface  sand. 

A  well  in  the  west  part  of  sec.  25,  South  Haven  Township,  is  in  till  from 
the  top  to  a  water-bearing  sand  at  bottom.  A  well  one-half  mile  southeast 
from  South.  Haven,  125  feet  in  depth,  is  in  till  except  5  feet  of  water-bearing 
sand  at  bottom  Several  tubular  wells  in  the  village  of  South  Haven  have 
a  depth  of  about  100  feet.  After  penetrating  a  few  feet  of  surface  sand  they 
are  in  blue  till  nearly  the  whole  depth.  Some  of  the  shallow  wells  in  the 
villag-e  obtain  water  at  the  base  of  the  siniace  sand.  A  boring  at  the  basket 
factory  in  South  Haven  has  the  following  section: 

Section  of  boring  at  basket  factory  in  South  Raven,  Michigan. 

Feet. 

Surface  sand 10 

Soft  blue  clay,  slightly  pebWy,  liecommg  liarder  toward  bottom  and  containing  bowlders  in  the 

lower  20  feet 130 

Shale  of  dark  color,  varying  in  hardness 207 

Total 347 

On  the  plain  east  of  Covert  Ridge,  in  sec.  31,  Geneva  Township,  a  flow- 
ing well  was  obtained  on  the  farm  of  J.  Irving  Pearce.  Water  rises  7  feet 
above  the  surface.  The  drift  is  mainly  a  blue  till  and  has  a  depth  of  190 
feet.     The  well  was  continued  40  feelj  into  the  underlying  shale. 

A  well  on  the  plain  east  of  Covert  Ridge,  in  sec.  29,  Casco  Township, 
Allegan  County,  reached  a  depth  of  140  feet  without  entering  rock.  After 
penetrating  25  feet  of  surface  sand  it  passed  through  a  thin  bed  of  blue 
pebbly  clay,  beneath  which  it  was  entirely  through  fine  sand. 

On  Covert  Ridge,  in  sec.  25,  T.  1  N.,  R.  17  W.,  a  well  157  feet  in  depth 
penetrated  18  feet  of  surface  sand,  beneath  which  it  was  mainly  through  a 
blue-gray  till.  Another  well  in  the  same  section  penetrated  12  feet  of  sur- 
face sand,  beneath  which  it  was  in  a  blue  till  to  a  depth  of  146  feet.  A 
well  in  the  northeast  corner  of  the  same  section  penetrates  scarcely  any 
surface  sand;  there  is  instead  a  loamy  yellow  till  7  feet  in  depth,  overlying 
the  blue  till.  The  latter  is  slightly  pebbly  and  extends  to  a  depth  of  104 
feet.  There  is  then  about  10  feet  of  stony  material  of  reddish-brown  color. 
This  is  underlain  by  blue  clay,  which  extends  to  the  water-bearing  sand  at 
130  to  134  feet. 

MON  XXXVIII 26 


402  THE  ILLlISrOIS  GLACIAL  LOBE. 

A  well  in  sec.  fi,  on  the  inner  slope  of  Covert  Ridge,  has  tlie  following 

section : 

Section  of  ivell  on  Covert  Ridge  in  sec.  6,  T.  1  N.,  R.  17  ir. 

Feet. 

Surface  sand 12 

Blue  clay,  slightly  pebbly 10 

Fine  white  sand  with  a  few  pebbles 32 

Cemented  gravel  alternating  with  beds  of  loose  gravel 24 

Total 78 

In  sec.  12,  T.  1,  R.  17,  also  on  the  inner  slope  of  Covert  Ridge,  wells 
30  to  50  feet  in  depth  are  mainly  through  sand,  and  the  lake  border  from 
this  point  northward  is  heavily  coated  with  sand. 

On  the  outer  slope  of  Covert  Ridge,  in  northern  Casco  TownSliip,  till 
appears  to  have  been  deposited  upon  a  thick  bed  of  sand.  The  wells  enter 
this  sand  at  a  depth  of  10  to  25  feet,  and  those  sunk  to  a  depth  of  35  or  40 
feet  do  not  reach  the  bottom. 

On  a  swamp  south  of  Covert  Ridge,  in  southeastern  Ganges  Township, 
wells  usually  pass  through  a  compact  clay  after  leaving-  the  surface  muck, 
and  find  some  difficulty  in  obtaining  water  in  dry  seasons.  A  well  in  sec. 
36  reached  a  depth  of  98  feet  and  found  only  a  weak  vein  at  about  40  feet. 

A  well  on  the  crest  of  Covert  Ridge,  in  sec.  16,  Ganges  Township,  at 
an  altitude  about  100  feet  above  the  lake,  reached  a  depth  of  275  feet  with- 
out entering  rock.     Its  section  is  as  follows: 

Section  of  toell  on  Covert  Ridf/e,  in  Ganges  Township,  Allegan  Cotmty,  Michigan. 

Feet. 

Surface  sand 6 

Blue  till fi^ 

Blue  quicksand 1* 

Yellow  sandy  clay  with  pebbly  layers loO 

Blue  till ■-■ -''    • 

Yellow  sandy  clay,  chauging  to  saud  at  bottom  , 30 

A  well  in  the  northwest  part  of  sec.  15,  also  on  the  crest  of  Covert 
Ridoe,  penetrated  30  feet  of  surface  sand,  beneath  which  was  a  blue  till 
extending  to  the  water-bearing  sand  at  86  feet. 

A  well  on  the  crest  of  the  ridge,  near  the  line  of  sees.  3  and  4,  at  an 
altitude  105  feet  above  the  lake,  reached  a  depth  of  190  feet  without  eiiter- 
iuo-  rock.  There  is  8  feet  of  yellow  till  at  the  surface,  beneath  which  the 
well  apnears  to  have  been  entireh'  in  a  blue-gray  till. 

In  the  vicinit)'  of  Hutchinson's  Lake  the  wells  range  in  depth  from  40 
to  105  feet  and  are  largely  through  sand  or  sandy  gravel. 


THE  LAKE-BOEDEE  MOEAINIC  SYSTEM.  403 

At  Fennville  wells  in  some  cases  penetrate  50  feet  of  sand,  with  which 
there  are  thin  beds  of  peaty  material  associated.  A  hill  east  of  this  village, 
which  stands  about  50  feet  above  the  level  of  the  railway  station,  has  till  at 
the  surface. 

At  Drenthe,  on  the  inner  slope  of  Covert  Ridge,  in  southern  Ottawa 
County,  flowing  wells  have  been  obtained;  one  in  a  ravine  at  the  sawmill 
has  a  head  8  feet  above  the  surface  and  will  flow  80  barrels  per  day  from 
a  2-inch  pipe.  The  water  is  obtained  from  sand  below  blue  till  at  a  depth 
of  92  feet.  Another  well  a  few  rods  Avest  is  siphoned  into  a  trough  in 
the  same  ravine.  A  well  1  mile  north  of  Drenthe,  155  feet  in  depth,  is 
mainly  through  blue  till,  except  in  the  lower  15  feet,  where  water-bearing- 
sand  and  gravel  is  found.  Its  head  is  sufficient  to  barely  reach  the  surface. 
Manv  wells  along-  the  ridge  east  and  south  from  Drenthe  have  been  sunk 
to  a  depth  of  100  feet  or  more,  mainly  through  blue  till.  The  till  sheet 
extends  westward  from  this  ridge  to  the  shore  of  Lake  Michigan  in  north- 
western Allegan  County. 

CHARACTER    OF.  THE    OUTWASH. 

The  Valparaiso  morainic  system  formed  a  retaining  wall  for  waters 
escaping  from  the  ice  sheet  along-  the  outer  border  of  the  ridges  xmder  dis- 
cussion, except  at  the  "Chicago  Outlet,"  and  possibly  at  the  St.  Joseph 
River  Valley.  It  is  probable  therefore  that  the  district  between  the  ice 
margin  and  the  Valparaiso  morainic  system  was  occupied  either  by  lakes 
or  by  very  sluggish  streams,  except  perhaps  for  a  few  miles  in  Lake  and 
northern  Cook  counties,  Illinois.  There  are  found  indications  of  a  moderate 
rate  of  flow,  accompanied  by  gravelly  outwash,  along  the  Des  Plaines 
Valley  below  the  jioint  where  the  outer  ridge  crosses  the  river  near  Griirnee. 
The  force  of  the  current  was  sufficient  to  carry  the  gravel  as  far  down  the 
valley  as  the  vicinity  of  Des  Plaines  Village  and  form  a  belt  a  mile  or  more 
in  average  width.     The  gravel  is  only  a  few  feet  in  depth. 

Much  of  the  low  country  bordering  these  ridges  in  southern  Cook 
County,  Illinois,  and  in  northwestern  Indiana  and  southwestern  Michigan 
has  been  covered  by  the  waters  of  Lake  Chicago,  and  the  deposits  made  by 
this  lake  can  not  easily  be  separated  from  any  deposits  of  similar  character 
which  nvAv  have  been  formed  as  an  outwash  from  the  ice  sheet.     There  are 


404  THE  ILLINOIS  GLACIAL  LOBE. 

places  wnere  wells  encounter  a  more  pebbly  material  at  the  base  of  the 
sand  than  near  the  surface,  but  it  is  not  certain  that  these  pebbles  were  an 
outwash  from  the  ice  sheet.  Indeed,  it  seems  quite  probable  that  they  may 
have  been  worked  over  and  deposited  by  the  waters  of  the  lake. 

ASSOCIATED   TILL  PLAINS. 

The  ridges  just  discussed  occupy  but  a  small  portion  of  the  area 
embraced  between  the  Valparaiso  morainic  system  and  the  shore  of  Lake 
Michigan.  The  greater  part  of  the  area  is  a  plain,  underlain  by  till  deposits. 
The  plane  tracts,  as  is  shown  later,  were  largely  covered  by  Lake  Chicago 
and' have  received  deposits  of  sand  or  gravel  from  the  waters  of  that  lake. 

ALTITUDE    AND    SLOPES. 

In  the  portion  of  the  plain  west  and  south  from  Chicago  the  altitude 
at  the  inner  border  of  the  Valparaiso  morainic  system  is  40  to  50  feet  above 
Lake  Michigan.  From  this  border  there  is  a  e-radual  descent  toward  the 
lake,  and.  the  till  scarcely  rises  above  lake  level  along  the  present  shore 
within  the  limits  of  the  city.  At  the  time  the  upper  or  Grlenwood  beach 
was  formed  lake  water  covered  the  entire  plain  west  and  south  of  the  city 
as  far  as  the  borders  of  the  Valparaiso  morainic  system,  the  altitude  of  that 
beach  being  55  to  60  feet  above  the  present  lake  level. 

Upon  passing  northward  this  till  plain  is  divided  into  several  narrow 
plains  which  separate  the  till  ridges,  and  these  plains  soon  rise  above  the 
level  of  the  upper  beach.  The  plain  that  lies  between  the  west  ridge  and 
the  Valparaiso  moraine  slopes  eastward  at  the  rate  of  several  feet  per  mile. 
Its  rise  toward  the  north  amounts  to  but  IJ  to  3  feet  per  mile.  At  Oving- 
ton  Station,  on  the  Omaha  Division  of  the  Chicago  and  Northwestern  Rail- 
way, the  west  border  next  the  Valparaiso  moraine  is  but  635  feet.  It  rises 
to  about  690  feet  at  the  line  of  Cook  and  Lake  counties,  a  distance  of 
18  miles,  and  to  about  725  feet  in  northern  Lake  County,  a  distance  of  24 
miles  farther.  The  i)lain  between  West  and  Middle  ridges  rises  from  030 
feet  at  Oak  Glen  to  680  feet  at  Deerfield,  a  distance  of  6  miles.  From 
Deerfield  north  to  the  State  line,  a  distance  of  24  miles,  it  is  shown  by  the 
Chicago,  Milwaukee  and  St.  Paul  Railway  profile  to  stand  at  (5 70  to  (i85 


THE  LAKE  BOEDER  MOEAINIC  SYSTEM.  405 

feet.  Russell  Station,  situated  on  this  plain  near  the  State  line,  is  673  feet. 
The  plain  between  Middle  and  East  ridges  rises  from  630  feet,  opposite 
Winnetka,  to  about  670  feet  at  the  point  where  the  ridges  unite,  20  miles 
north  from  Winnetka. 

In  Indiana  the  border  next  the  Valparaiso  morainic  system  stands  50 
to  70  feet  above  Lake  Michigan,  the  lesser  altitude  being  near  the  Illinois 
line  and  the  greater  near  the  Michigan  line.  The  plain  between  the  Val- 
paraiso moraine  and  the  outer  till  ridge  is  but  2  to  3  miles  Avide  in  Porter 
and  Laporte  counties;  it  however  shows  a  descent  toward  Lake  Michigan. 
There  is  also  a  percej^tible  descent  from  the  till  ridge  toward  the  lake.  In 
western  Porter  and  in  Lake  counties  the  slope  is  apparently  continuous 
toward  the  lake  from  the  border  of  the  Valparaiso  morainic  system,  no  well- 
defined  till  ridge  being  present.  For  a  distance  of  2  to  5  miles  south  from 
the  lake  the  sand  deposits  capping  the  till  are  heavy  and  their  base  is  about 
as  low  as  the  surface  of  Lake  Michigan. 

In  Berrien  County,  Michigan,  the  plain  between  the  Valparaiso  morainic 
system  and  the  outer  till  ridge  stands  60  to  90  feet  above  Lake  Micliigau 
and  has  a  slight  descent  toward  the  lake.  As  it  is  but  2  to  4  miles  in  width, 
the  west  border  is  only  a  few  feet  lower  than  the  east.  The  plain  between 
the  outer  ridge  and  Covert  Ridge  stands  50  to  75  feet  above  Lake  Michigan, 
and  also  has  a  slight  descent  toward  the  lake.  Its  width  in  places  is  less 
than  a  mile  and  nowhere  exceeds  3  miles. 

In  Van  Buren  and  Allegan  counties  the  lowland  tract  between  the  Val- 
paraiso morainic  system  and  Covert  Ridge  is  less  smooth  than  the  southward 
continuation  in  Berrien  County.  There  are  occasional  ridges  and  knolls  of 
glacial  drift  ranging  in  height  from  50  feet  downward  to  10  feet  or  less. 
There  are  also  numerous  sandy  ridges  and  knolls  with  a  heiglit  ranging 
from  30  feet  downward  to  barely  detectible  waves  in  the  surface.  The 
presence  of  the  sand  has  tended  to  make  the  surface  more  uniform  in  eleva- 
tion, since  it  is  deeper  in  depressions  than  on  the  higher  points.  The  plane- 
surfaced  part  of  the  lowland  stands  usually  75  to  100  feet  above  Lake  Michi- 
gan, while  the  knolls  occasionally  reach  a  height  of  150  feet  or  more  above 
the  lake.  This  lowland  tract  presents  greater  oscillations  in  level  in  passing 
from  north  to  south  than  from  west  to  east.  It  is  generally  somewhat  lower 
on  the  borders  of  the  valleys  than  on  the  divides  between  them.     If  the 


406  THE  ILLINOIS  GLACIAL  LOBE. 

sand  were  removed  the  variations  would  be  still  greater,  since  the  sand  is 
thicker  on  the  borders  of  the  valleys  than  on  the  divides. 

Covert  Ridge  follows  the  shore  of  Lake  Michigan  so  closely  that  a 
plain  is  present  on  its  inner  border  along  only  a  small  part  of  its  course  from 
the  State  line  northward  to  the  Kalamazoo  River.  Where  present  it  shows 
a  descent  of  20  or  30  feet  per  mile  toward  the  lake.  In  places  where  the 
ridge  is  distant  2  or  3  miles  and  its  inner  border  stands  60  to  70  feet  above 
the  lake  the  till  surface  drops  down  nearly  to  lake  level  at  the  lake  shore. 
Sand  deposits  have  considerable  depth  on  the  lower  parts  of  this  plain  and 
bring  the  surface  up  to  a  height  of  35  to  40  feet  or  more  above  the  lake. 

THICKNESS    OF    DRIFT. 

On  the  Illinois  portion  of  these  plains  there  is  much  difference  in  the 
thickness  of  the  drift.  The  difference  in  thickness  is  due  almost  entirely  to 
the  variation  in  the  surface  of  the  underlying  rock  strata,  since  the  surface 
of  the  plains  has  only  a  slight  variation  in  altitude.  Within  the  city  of 
Chicago,  where  the  surface  is  especially  flat,  several  rocky  prominences 
come  to  the  surface,  or  are  concealed  but  slightly  by  drift,  while  among 
them  the  di-ift  accumulations  extend  to  depths  of  100  to  125  feet  or  more. 
Mr.  Samuel  Gr.  Artingstall,  formerly  city  engineer,  has  prepared  a  map  of 
the  city  showing  the  distance  to  rock  in  many  places.  This  indicates  that 
a  filled  valley  with  rock  floor  100  to  125  feet  below  lake  level  passed 
through  the  north  central  part  of  the  city,  entering  the  lake  south  of  Lin- 
coln Park.  West  from  the  city  the  rock  rises  over  quite  extensive  areas 
nearl)'  to  the  surface  of  the  jjlain  or  to  a  height  of  30  to  60  feet  above  the 
level  of  Lake  Michigan. 

In  northern  Cook  and  in  Lake  County,  betAveen  the  till  ridges  as  well 
as  beneath  them,  the  rock  surface  has  an  average  altitude  somewhat  lower 
than  in  the  low  plain  in  the  vicinity  of  Chicago,  for  the  majority  of  the 
wells  reach  a  level  about  50  feet  below  the  surface  of  Lake  Michigan 
before  entering  rock.  It  is  estimated  that  the  thickness  of  drift  in  this 
northern  portion  will  average  nearly  150  feet,  while  in  the  low  plain  the 
average  will  scarcely  exceed  50  feet. 

The  thickness  of  drift  in  the  Indiana  and  ^Michigan  portions  is  usually 
great,  as  has  been  indicated  above.     (See  pages  302-393.) 


THE  LAKE-BOEDER  MOEAINIG  SYSTEM.  407 

STRUCTURE    OF-  THE   DRIFT. 

The  di-ift  beneath  the  Ilhnois  portion  of  these  till  plains,  like  that  of 
the  ridges,  consists  largely  of  a  soft  blue  till,  beneath  which  are  remnants 
of  a  hard  till  of  earlier  age.  The  tills  appear  to  be  of  direct  glacial  depo- 
sition, even  in  portions  of  the  plain  which  lie  within  the  limits  of  the 
beaches.  The  clayey  matrix  of  the  soft  till  seems  to  be  less  thickly  set 
with  stones  than  that  of  the  underlying  hard  till,  but  in  both  tills  many  of 
the  stones  are  glaciated  and  show  little  evidence  of  water  abrasion.  The 
rocky  constituents  grade  from  bowlders  several  feet  in  diameter  down  to 
minute  pebbles.  These,  in  the  upper  or  later  till,  are  made  up  In  large 
part  from  the  local  upper  Silurian  rocks,  probably  less  than  10  per  cent 
being  from  the  pre-Cambrian  Canadian  rocks.  Frag-ments  of  Devonian 
rocks,  apparently  from  ledg-es  outcropping  to  the  north  of  Chicago,  are 
sparingly  represented.'  The  clayey  matrix  is  highly  calcareous,  and  under 
the  microscope  it  is  found  that  angular  or  but  slightly  rounded  grains  of 
limestone  constitute  a  large  proportion  of  the  fine  material.  With  the 
minute  limestone  fragments  there  appear  quartz  grains,  bits  of  shale,  and 
fragments  from  crystalline  rocks  of  various  kinds.  Whether  the  rock  con- 
stituents  of  the  older  till  diflPer  markedly  from  those  of  the  newer  has  not 
been  ascertained.  Its  situation  immediately  upon  the  Lockport  (Niagara) 
limestone  would,  in  all  probability,  result  in  the  incorporation  of  an  even 
larger  proportion  of  fragments  from  this  rock  than  appears  in  the  upper  till. 

One  of  the  most  conspicuous  instances  of  the  occurrence  of  the  lower 
till  within  this  area  is  that  brought  to  light  in  the  excavation  of  the  Chicago 
Drainage  Canal.  Immediately  east  from  Summit  the  canal  for  about  a 
mile  extends  a  few  feet  into  a  very  hard,  partially  cemented  till,  apparently 
of  early  glacial  age.  Its  hardness  compared  with  that  of  the  overl}ang  till 
is  so  marked  that  the  contractors  who  engaged  to  excavate  this  part  of  the 
channel  were  obliged  to  abandon  the  steam  shovel  which  had  been  used  in 
the  soft  till  and  to  resort  to  blasting.  It  is  probable  that  this  old  di'ift  fills 
depressions  in  the  rock  quite  extensively  in  this  district,  but  as  no  special 
attention  has  been  given  its  identification  the  instances  recognized  are  not 

'  On  tbe  microscopic  structure  of  certain  bowlder  clays,  and  the  organisms  contained  in  them, 
by  Dr.  George  M.  Dawson :  Bull.  VI,  Chicago  Academy  of  Sciences. 


408  THE  ILLINOIS  GLACIAL  LOBE. 

numerous.  The  well  drillers  usually,  distinguish  the  hard  till  from  the  over- 
Iving  softer  till  and  apply  to  it  the  name  "hardpau,"  while  the  soft  till  is 
called  clay. 

Although  the  great  body  of  the  drift  is  till,  there  are  found  numerous 
thin  beds  of  sand  or  gi'avel  in  which  water  collects  in  sufficient  quantities 
to  supply  the  wells.  There  are  also  small  pockets  of  dry  sand  or  gravel 
occupying  but  a  few  cubic  feet  each.  Such  pockets  were  foiuid  in  the  exca- 
vation of  the  main  lake  tunnel,  and  have  been  described  b}-  Dr.  Edmund 
Andrews  in  a  paper  published  in  the  American  Journal  of  Science.^  They 
were  in  some  cases  completely  inclosed  by  till. 

On  the  surface  of  the  plain  both  above  and  below  the  upper  beach 
there  is  quite  generally  present  in  Lake  and  Cook  counties  a  clay  in  which 
pebbles  are  far  less  numerous  than  in  the  till;  it,  however,  can-ies  occasional 
bowlders.  It  rang-es  in  thickness  from  a  few  inches  up  to  several  feet.  This 
deposit  is  perhaps  a  subaqueous  till  dropped  in  a  body  of  water  held 
between  the  ice  front  and  the  higher  parts  of  the  moi'ainic  system  while 
the  ice  sheet  was  still  overhanging  the  inner  slope. 

The  depth  of  leaching  and  oxidation  is  markedly  less  on  the  plain 
covered  by  Lake  Chicago  than  on  the  till  ridges  or  the  Valparaiso  morainic 
system.  Numerous  acid  tests  show  the  leaching  on  the  plain  to  extend 
only  to  a  depth  of  a  few  inches,  seldom  more  than  2  feet.  On  the  till  ridges 
the  leaching  is  usually  thorough  to  a  deptli  of  3  or  4  feet,  while  on  the 
Valparaiso  system  it  is  rare  to  obtain  a  response  with  acid  within  5  or  6  feet 
of  the  surface.  On  the  plain  and  also  on  the  till  ridges  the  surface  oxida- 
tion is  usually  but  3  to  6  feet,  while  on  the  Valparaiso  system  it  is  6  to  10 
feet  or  more.  This  difference  in  the  amount  of  oxidation  and  leaching  may 
be  attributable  in  part  to  the  more  compact  nature  of  the  till  ridges  and 
plains,  but  it  is  probably  in  part  due  to  the  later  date  at  which  they  became 
exposed  to  atmospheric  action. 

There  have  been  several  deep  lines  of  excavation  made  in  Chicago  and 
vicinity  which  have  affoi*ded  excellent  opportunities  for  studying  the  struc- 
ture of  the  drift.  Tlie  longest  line  is  the  Drainage  Canal,  now  imder  con- 
struction, which  ojjcns  a  channel  25  to  40  feet  in  depth  from  the  Chicago 
River  at  Bridgeport  to  the  Des  Plaines  River  at  Summit.     Along  the  Des 

'  Atti.  .lour.  Rci.,  2il  scries,  vol.  13,  TRfiT,  ]ip.  7.^-77. 


THE  LAKE-BOEDEE  MOEAINIO  SYSTEM.  409 

Plaines  also  the  excavation  is  larg-ely  in  drift  to  the  vicinity  of  Lemont, 
where  the  canal  becomes  a  rock  channel.  From  Bridgeport  to  Summit  there 
is  little  besides  till,  but  from  Summit  to  Lemont  gravel,  sand,  and  the  coarser 
material  deposited  or  left  as  a  residue  along  the  line  of  the  old  lake  outlet 
form  a  large  part  of  the  section. 

In  the  Fullerton  avenue  conduit,  which  leads  eastward  into  the  lake 
through  the  north  part  of  Chicag-o,  the  drift  is  mainlj^  till,  but  surface  sand 
is  a  conspicuous  deposit.  From  its  western  end  to  within  2,000  feet  of  the 
lake  the  rock  surface  is  found  at  a  depth  of  43  to  54  feet.  Within  100  feet 
east  from  this  point  it  drops  down  to  80  feet,  passes  below  the  conduit,  and 
does  not  appear  farther  east.  The  surface  sand  has  its  greatest  thickness  at 
about  1,700  feet  from  the  lake,  where  it  reaches  25  feet.  It  decreases  west- 
ward to  only  12  feet  at  a  distance  of  6,000  feet  from  the  lake,  and  entirely 
disappears  before  reaching-  the  Chicago  River  Valley.  Toward  the  lake 
shore  also  it  decreases,  but  holds  a  thickness  of  about  18  feet  for  1,400  feet 
from  the  shore.  At  the  water's  edge  the  depth  is  but  10  feet.  The  profile 
continues  out  1,100  feet  beneath  the  lake,  and  there  is  but  3  feet  of  sand  at 
its  terminus 

Numerous  borings  and  excavations  in  the  south  part  of  Chicago,  in 
Hyde  Park  Township,  show  sand  deposits  ranging  in  depth  from  5  feet  or 
less  up  to  about  20  feet.  Till  usually  underlies  the  sand  except  where  the 
rock  comes  near-  the  surface.  In  this  connection  it  may  be  remai'ked  that 
the  heavy  deposits  of  sand  in  Cook  County  are  found  chiefly  along  the 
present  lake  border  from  Evanston  southward,  where  there  is  a  continuous 
belt  of  sand  ranging  in  width  from  one-half  mile  to  3  or  4  miles  and  having 
an  average  depth  of  not  less  than  10  feet.  Over  much  of  the  plain  west 
of  this  sandy  belt  the  deposition  was  so  light  as  scarcely  to  conceal  the 
surface  bowlders  and  in  places  leaves  only  a  trace  of  sand  in  the  soil.  The 
south-westward  lake  outlet  appears  to  have  carried  away  much  of  the  sand 
which  was  brought  into  the  southern  end  of  the  lake  while  that  outlet  was 
open.  , 

In  the  portion  of  Indiana  between  the  Valparaiso  morainic  system  and 
Lake  Michigan  sand  deposits  are  heavj^  as  far  south  as  Calumet  River  in 
Lake  and  western  Porter  counties  and  nearly  as  far  as  the  inner  border  of 
the  till  ridge  in  northeastern  Porter  and  northwestern  Laporte  counties,  a 


410  THE  ILLINOIS  GLACIAL  LOBE. 

belt  whose  width  varies  from  scarcely  2  miles  up  to  iully  5  miles.  Where 
the  duues  are  highest  the  sand  probably  has  a  thickness  of  about  200  feet, 
for  the  dunes  attain  a  heig-ht  of  150  to  175  feet,  and  the  sand,  as  shown  by 
wells,  extends  a  few  feet  below  the  lake  level.  Throughout  much  of  the 
belt  the  sand  probably  exceeds  25  feet  in  depth  and  may  average  twice  that 
amount.  South  of  Calumet  River,  from  the  mouth  of  Salt  Creek,  near 
Chrisman  westward  past  Lake  and  Liverpool  to  Griffith,  there  is  a  belt  of 
sand  a  mile  or  more  in  width  which  has  generally  a  depth  of  about  20  feet. 
East  from  Salt  Creek  the  depth  is  much  less.  The  sand  is  also  of  slight 
depth  west  from  Griffith  except  along  the  line  of  the  beaches. 

Beneath  this  heavy  deposit  of  sand  there  appears  to  be  but  little  oxi- 
dized clay,  a  feature  which  favors  the  interpretation  that  the  clay  was  not 
long  exposed  to  atmospheric  action  before  the  sand  deposition  occun-ed. 
The  wells  usually  pass  immediately  into  a  blue  clay.  This  clay,  so  far 
as  can  be  learned  from  well  drillers,  is  but  slightly  pebbh'  and  appar- 
ently is  in  places  free  from  pebbles.  It  seems  to  maintain  this  character 
to  great  depth,  as  is  indicated  by  sections  of  wells  already  given.  It  differs 
markedly  from  the  blue  till  of  the  neighboring  portion  of  the  plain  in 
Cook  County,  Illinois,  and  appears  also  to  be  somewhat  less  pebbly  than 
the  blue  clay  of  the  neighboring  district  in  southwestern  Michigan.  There 
are  few  exposures  afforded  by  the  streams  in  the  district  where  sand  is 
heavy,  but  exposures  of  slight  depth  are  numerous  outside  the  limits  of 
the  heavy  sand.  From  these  exposures  it  appears  that  the  clay  has  gener- 
ally but  few  pebbles,  and  several  exposures  have  been  found  in  which  it  is 
pebbleless. 

The  most  extensive  exposures  of  pebbleless  clay  noted  are  along  Deep 
River,  in  the  vicinity  of  Hobart,  and  it  appears  to  be  present  over  an  area 
of  several  scjuare  miles  between  Deep  River  and  Salt  Creek.  Prof.  W.  S. 
Blatchley,  State  geologist,  reports  a  similai-  clay  at  Chesterton  and  Michi- 
gan City.^  This  pebbleless  clay  is  oxidized  to  a  depth  of  a  few  feet, 
beneath  wliich  it  presents  a  blue  color  similar  to  that  of  the  ])ebbly  clay  of 
neighboring  districts.  It  is  highly  calcareous  and  carries  numerous  lime- 
stone nodules  near  the  bottom  of  the  oxidized  portion.  It  seems  even  more 
calcareous  than  the  pebbly  blue  clay.     Professor  Blatchley  has  published 

'Coinmnnicated  to  tlio  writer. 


THE  LAKE-BOEDER  MORAINIC  SYSTEM. 


411 


the  following  analyses  of  samples  of  these  pebbleless  clays,  made  by  Prof 
W.  A.  Noyes.  of  Terre  Haute,  Indiana.^ 

Analyses  of  clays  of  Pleistocene  age. 


Hobart. 

Garden 
City. 

Chesterton. 

Michigan 
City. 

Silica               -         

Per  cent. 

50. 56 

1.00 

13.11 

2.76 

Per  eent. 

50.37 

.65 

9.93 

1.50 

Per  cent. 

53.02 

1.30 

10.72 

2.21 

Per  cent. 
50.47 

1.45 
12.77 

3.14 

Combined  water       .          

Total  clay  V)a8e  and  sand  . . . 
i^erric  oxide     -. , _-.- 

67.43 

62.45 

67.25 

67.83 

2.98 
2.32 
7.87 
5.06 
3.74 
.70 

2.10 
2.05 
10.26 
6.26 
3.04 
.79 

2.54 
2.22 
8.38 
5.28 
3.25 
.86 

2.44 
2.52 
8.17 
5.22 
3.70 
.73 

Ferrous  oxide        . 

Soda 

Total  fluxes           

22.67 
9.62 

24.50 
12.50 

22.53 
10.48 

22.78 
9.80 

Carbon  di oxide 

Total  

99.72 

99.45 

100. 26 

100. 41 

In  explanation  of  the  contrast  in  the  amount  of  coarse  material  in  the 
clays  bordering'  the  lake  in  northwestern  Indiana,  compared  with  those  in 
Cook  County,  Illinois,  it  may  be  remarked  that  it  is  probable  that  the  char- 
acter of  the  underlying  rocks  will  prove  an  important  factor.  In  Cook 
County,  Illinois,  the  underlying  rocks  are  the  somewhat  resistant  Lockport 
(Niagara)  limestone,  while  in  the  neighboring  portion  of  Indiana  the  rocks 
immediately  beneath  the  drift  are  the  Devonian  shales,  which  are  easily  com- 
minuted and  ground  into  a  clayey  material.  It  is  probable,  however,  that 
the  conditions  of  deposition  were  slightly  different  in  the  two  districts.  In 
Cook  County  the  southwestward  line  of  discharge  may  have  been  open 
sufficiently  to  allow  a  considerable  part  of  the  fine  material  to  be  carried 
down  the  Des  Plaines  Valley,  while  in  the  Indiana  district  it  may  all  have 
been  deposited  without  much  transportation  or  sifting  out  of  the  finer 
material.  The  localities  where  the  pebbleless  clay  are  best  exposed  are 
beneath  the  bay-like  extensions  of  Lake  Chicago,    and  may  possibly  be 

1 22d  Ann.  Kept.  Indiana  Geol.  Survey,  1898,  pp.  128,  134,  1.S7,  and  139. 


412 


THE  ILLINOIS  GLACIAL  LOBE. 


composed  of  sediment  wliich  settled  in  the  waters  of  the  bays.  The  g-reat 
amount  of  calcareous  material,  however,  seems  to  indicate  that  they  are  a 
glacial  rather  than  lacustrine  silt.  The  scarcity  of  evidence  of  life  in  the 
earh'  stages  of  the  lake  seems  to  indicate  that  but  little  calcareous  material 
can  be  looked  for  from  that  source. 


SECTION  VI.  STRIDE  WITHITs^  LIMITS  OF  SHEIiBY^'ILIiE  MORAIXE. 

The  table  of  stria;  given  below  includes  all  exposures  of  which  the 
writer  has  knowledge  either  through  personal  observations  or  from  publica- 
tions and  correspondence.  There  are  several  observations  taken  by  Messrs. 
J.  T.  Campbell,  0.  P.  Jenkins,  A.  H.  Purdue,  and  J.  A.  Udden,  hitherto 
unpublished,  which  have  been  kindly  contributed  for  publication  in  this 
report  The  bearings  taken  by  the  writer,  except  when  so  designated,  are 
not  corrected  for  magnetic  variation.  The  bearings  taken  in  western 
Indiana  by  Collett,  Campbell,  and  Jenkins  are  corrected  for  magnetic  varia- 
tion, but  so  far  as  known  all  others  are  magnetic.  The  magnetic  variation 
in  western  Indiana  is  only  about  3°  east  and  in  western  Illinois  6°  east.^ 

TaMe  o/stj-ue  within  limits  of  Shelby ville  moraine. 


Location. 


Bearing. 


Observer. 


Near  Troutman,  lud 8.8'=' E Collett. 

Coal  Creek  bluff,  3  miles  west  of  Wayueto-n-n S.  18°  E Collett. 

Coal  Creek  bluff,  3  miles  west  of  Waynetown  a S.  20°  W Hopkins. 

Near  Darlington,  Ind S.  31°  E Leverett. 

Near  Darlington,  Ind.  b S.  W Thompson. 

In  northern  Parke  Connty,  sec.  27,  T.  17,  R.  7  W ;  8.39°  48'  E '  Campbell. 

In  northern  Parke  County,  see.  27,  T.  17,  E.  7  W  o '   8.34°  30'  E '  Campbell. 

Williamsport,  Ind '  S.68°  E !  Leverett. 

Williamsport,  Ind.  if '  S.8°-10°  W  ...    Salisbury. 


a  See  Collett,  Geol.  of  Indi.ina  1875.  p.  370.  Also  Hoiikins,  Geol.  of  Inrti.ina,  180.i,  p.  273.  Tlie  observations  by  Mr. 
Hopkins  indicate  that  the  bearing  reported  by  Mr.  Collett  should  be  S.  18°  W. 

b  The  stria'  reported  by  Mr.  Mauriee  Tboiupsim  were  probably  formed  by  the  Krie  lobe. 

c  Two  exposures  on  the  bluflf  of  Sugar  Creek.  100  feet  apart,  show  a  difterence  of  5^  in  bearing.  The  observer,  Capt. 
J.  T.  Campbell,  of  Rockville,  Indiana,  has  reported  several  exposures  of  glacial  strirt'  in  Parke  and  Putnam  counties, 
Indiana,  which  bear  soiithwestward,  and  accordingly  are  referred  to  the  Alauniee  lobe.  They  are  discussed  in  alinther 
report  now  in  jireparation. 

d  The  observations  reported  by  Professor  Salisbury  probably  represent  a  inovemeut  connected  witll  the  "Wisconsin 
stage  c(f  glaciatitui.  wbile  the  observations  reported  by  the  writer  belong  apparently  to  an  earlier  glaciation.  Two  miles 
east  of  Williaiiispiirt,  on  the  north  side  of  tlie  "Wubash,  Professor  Cbamberliu  found  a  tliird  set  of  stria^  with  westward 
bearing,  which  appuroutly  pertain  to  the  invasion  of  the  Erie  lobe.     (See  Seventh  Annual  Keport  f.  S.  Geol.  Survey,  p.  207.) 

'  See  map  of  Henry  (lannett,  showing  distribution  of  magnetic  variation  in  the  United  States 
for  the  year  1900:  Seventeenth  Ann.  Kept.  U.  S.  Geol.  Survey,  Part  I,  PI.  II. 


STELE  WITHIN  LIMITS  OF  SHELBYVILLE  MORAINE. 

Table  of  strue  within  limits  of  Shelbyville  moraine — Continued. 


413 


Location. 


Near  Fountain  post-ofBce,  iu  sec.  i,  T.  20,  R.  8  W.,  main 
bearing. 

Near  Fountain  post-office,  in  sec.  4,  T.  20,  R.  8  W.,  scatter- 
ing stri;e. 

Logansport,  lud.,  on  banlv  of  Eel  River 


East  of  Logansport,  on  bed  of  Eel  River 

Mouou ,  Ind 

Mouou,  Ind.  a - 

Rensselaer,  Ind 

Quarry,  near  Kentland 

Quarry,  near  Kentland  a 

South  bluflf  of  Illinois  Elver,  near  Lasalle 

Mazon  Creek  blnif,  sec.  30,  T.  33N.,  R.  8E 

Near  Morris,  111.,  iu  sec.  24,  T.  34,  R.  7  E 

Near  Morris,  111.,  iu  sec.  19,  T.  34,  R.  8  E 

Near  Morris,  111. ,  in  sec.l8,  T.  34,  R.  8  E .' 

Near  Morris,  111. ,  iu  sec.  18,  T.  34,  R.  8  E 

In  Lisbon,  111 

Aux  Sable  Creek,  west  of  Minooka 

Aux  Sable  Creek,  sec.  9,  T.  35,  E.  8  E 

Brodie's. Quarry,  on  Fox  River  bliitf,  north  of  Millington,  III.. 


Little  Rock  Creek,  sec.  33,  T.  37,  R.  6  E. 


See.  34,  T.  37,  R.  6  E 

Sec.  1,T.37,  R.6E 

Joliet,  near  penitentiary 

Dupage  River   blnif,  at   crossing   of  Chicago,  Rock  Island 
and  Pacitic  R.  R. 

Kankakee  River  blufi',  in  sec.  9,  T.  33,  R.  9  E 

Near  Wilmington,  111.,  in  sec.  31,  T.  33,  E.  10  E 

Beckford's  Quarry,  sec.  10,  T.  33,  R.  11  E 

Lemont,  near  Des  Plaines  "Cut-off" 

Between  Willow  Springs  and  Sag  Bridge 

West  of  Summit 

North  of  Summit,  near  Santa  Fe  railway  bridge , 


Bearing. 


S.  40°  E  , 


S.56°-620E  ... 

S.  14°     E.    or 

N.  14°  W. 

S.58°  W 

S.34C  E 

S.  85°  W 

S.  8°-14°  W... 

S.70E 

S.77-W 

S.75°W 

S.44°W 

S.  .50°-55°  W.. 

S.  60°  W  

S.  30°-38°  W  - . 
S.  40°-55  W... 

S.  50°  W 

S.W 

S.  47°45'  W... 
S.  9°  30'  E.  to 

S.  27°  30'  W. 
S.  31°  AV.,  S. 

37°    W.,     S. 

40°  W. 

S.42°W 

S.  110°  30'  W  . 

S.96°W 

S.  42°  30'  W  . . 


S.  58°  W  . 
S..43°  W  . 
S.31°W., 
S.  60°W.. 
S.  18°W., 
S.34°W. 
S.86°W. 


Observer. 


Siebenthai. 

Siebenthal. 

Leverett. 

Leverett. 

Chamberlin. 

Chamberliu. 

Purdue. 

Chamberlin. 

Chamberlin. 

Leverett. 

Leverett. 

Leverett. 

Leverett. 

Bradley. 

Leverett. 

Leverett. 

Udden. 

Leverett. 

Leverett. 

Leverett. 


Leverett. 
Leverett. 
Leverett. 
Udden. 

Leverett. 

Leverett. 

Leverett. 

Guthrie. 

Leverett. 

Leverett. 

Leverett. 


ftAtMononand  near  Eentland  there  are  two  .system.s  of  strife  reported  by  Professor  Chamberlin.  In  the  latter 
instance  the  southward  pointing  stripe  lie  in  grooves  and  furrows  in  the  limestone,  while  the  "westward  pointing  striae  only 
aiJect  the  crests  of  these  furrows,  which  have  been  slightly  truncated  by  tlie  later  westward  movement.  (See  Seventh 
Annual  Report  U.  S.  Geol.  Survey,  p.  207.)  The  writer  made  an  observation  of  striae  2  miles  east  of  Kentland,  iu  which  they 
appear  at  various  angles  between  S.  4°  E.  and  S.  75°  W.,  in  such  manner  as  to  suggest  that  more  than  two  movements 
affected  the  rock  ledge. 


414  THE  ILLINOIS  GLACIAL  LOBE. 

Table  of  stria'  within  limits  of  SlielbyviUe  moraine — Continued. 


Location. 

Bearing. 

Observer. 

T.ivnns    in  T)es  Plaines  A'^allev                                               .-    .. - 

S.    40-    W.    to 
S.  6T^  W. 

S.54°W 

S  67- W 

Leverett. 

Leverett. 

East  of  Elmburst,  in  sec.  17.  T.  39,  R.  12  E 

Hawthorne  quarries,  west  })art  of  Chicago 

Quarry  at  Western  and  Chicago  avenues,  Chicago 

Piinprton  avenue  conduit   Chica*^o                              

S.58^-\V 

S.  60^-64=  W--. 

S.68°W 

S.60=W 

S.480-55-AV.-. 
S.30°-oO=W... 
R.oO-AV    

Leverett. 
Leverett. 
Leverett. 
Citv  engineer. 

Quarry  at  Eighteenth  and  Robey  streets,  Chicago 

Stonv  Tsla.iid..  South  Chica^'o 

Leverett. 

Leverett. 

Leverett. 

Gnthrie. 

Leverett. 

Blue  Island  iiuarries,  2  miles  soutUvrest  of  village 

Thornton,  in  valley  east  of  village  a 

E.-W 

S.27-W 

ffiilr.  Ossian  Guthrie  reports  having  observed  strise  at  Thornton  bearing  more  nearly  westward.  {See  Guthrie's 
pamphlet  on  the  Lake  Michigan  Glaciers,  map  3.) 

Considerable  difficulty  i.s  experienced  in  assigning  stria?  in  northwestern 
Indiana  to  tlie  proper  ice  lobe.  That  district  was  invaded  from  the  north- 
ward by  the  Illinois  lobe  and  subsequently  from  the  eastward  by  another 
portion  of  the  ice  sheet,  the  Saginaw-Erie  lobe,  which  in  the  closing  stages 
of  glaciation  became  differentiated  into  the  Siiginaw  lobe  and  the  Erie  or 
Maumee  lobe.  Accordingly  both  southward  and  westward  bearing  strise 
are  found.  In  some  places,  as  at  Monon  and  Kentland,  a  single  rock  sur- 
face presents  both  southward  and  westward  bearing  stria?,  the  west^^'ard 
beino-  the  later.  Usually,  however,  the  sti'ite  formed  by  the  earlier  ice 
movement  were  either  protected  by  drift  deposits  from  the  action  of  the 
later  ice  movement,  or  they  were  so  exposed  as  to  be  effaced  by  tlte  later 
movement. 

There  are  strise  on  the  north  bank  of  Eel  River  in  the  city  of  Logans- 
port,  concerning  which  the  direction  of  movement  is  not  certain.  The 
bearing  is  N.  14°  W.  or  S.  14°  E.  Immediately  north  of  Logansport  lies 
a  heavy  moraine  formed  on  the  north  border  of  the  Erie  lobe,  wliich,  as 
just  noted,  extended  westward  from  the  Lake  Erie  Basin.  We  may  sup- 
pose the  stria'  to  have  been  formed  h\  ;i  northward  movement  toward  this 
moraine,  but  it  is  quite  as  probable  that  tliey  were  formed  by  an  earlier 
soutliward  movement,  independent  of  the  moraine  and  perhaps  referable  to 


STEI^  WITHIN  LIMITS  OF  SHELBYVILLB  MOEAmE.  415 

the  Illinois  lobe.  A  careful  examination  of  the  striated  surface  failed 
to  disclose  decisive  evidence  whether  the  movement  was  northward  or 
southward.  It  may  be  remarked  in  this  connection  that  just  above  the  city 
of  Logansport  the  bed  of  Eel  River  shows  heavy  glacial  grooves  bearing 
S.  58°  W.,  which  are  evidently  the  product  of  the  movement  from  the 
Lake  Erie  Basin.  It  seems  scarcely  possible  for  the  same  ice  movement  to 
produce,  within  the  limits  of  a  single  township,  striae  with  bearing  differing 
108  degrees,  and  that  too  in  a  comparatively  smooth  region.  But  so  little 
is  known  as  yet  concerning  the  possibilities  of  ice  movement,  that  judgment 
should  perhaps  be  reserved. 

The  striae  of  northeastern  Illinois  show  some  interesting  deviations  from 
a  general  southwestward  course.  In  the  Des  Plaines  Valley  there  is  a  rr.nge 
from  S.  18°  W.  to  S.  96°  W.  Three  observations  between  Summit  and 
Lemont  show  bearings  S.  34°  W.,  S.  18°  W.,  and  S.  60°  W.  The  stria; 
bearing  nearest  westward  are  accompanied  by  heavy  grooves  which  seem 
to  call  for  the  action  of  a  thick  ice  sheet,  but  the  other  exposures  show  oidy 
faint  striation,  and  it  has  occurred  to  the  writer  that  jJossibly  this  faint 
striation  is  attributable  to  masses  of  ice  floating  down  the  valley  after  the 
ice  sheet  had  withdrawn.  Another  locality  in  northeastern  Illinois,  where 
the  striation  is  thought  to  be  referable  to  floating  ice,  is  on  the  bluff  of  Fox 
River,  north  of  Millington,  in  Kendall  County,  where  faint  striae  occur  with 
bearings  ranging  from  S.  9°  30'  E.  to  S.  27°  30'  W.  In  a  great  majority  of 
exposures  in  the  Illinois  district  glaciation  is  heavy,  with  complete  planing 
of  surface  and  often  with  heavy  grooves,  and  can  scarcely  be  referred  to 
floating  ice. 

At  Joliet  striae  were  observed  with  bearing  slightly'  north  of  west,  but 
this  bearing  is  almost  at  right  angles  with  the  trend  of  the  Minooka  till 
ridge  a  few  miles  west  of  Joliet,  and  is  probably  referable  to  the  ice  move- 
ment which  produced  that  ridge.  The  same  explanation  probably  should  be 
given  for  the  bearing  20°  north  of  west,  shown  in  an  exposure  a  few  miles 
west  of  Aurora  (sec.  1,  T.  37  N.,  R.  6  E.),  for  a  moraine  with  NE.-SW. 
trend  passes  through  the  distiict  immediately  northwest  of  these  striae. 

On  Stony  Island,  in  the  south  part  of  Chicago,  the  rock  quarrv  where 
glaciation  was  observed  has  beds  which  dip  toward  the  southeast  with  an 
angle  of  30  degrees  or  more.     Heavy  scorings  follow  the  line  of  strike,  with 


416 


THE  ILLIJTOIS  GLACIAL  LOBE. 


a  bearing  S.  44°  W.  Associated  with  these  are  strire  of  feebler  develop- 
ment,  wliich  vary  in  direction  fully  10  degrees  to  the  east  and  west  of  the 
heavy  scorings,  thus  ranging  from  S.  34°  to  S.  54°  W.  An  escarpment  of 
the  dipping  layers  which  rises  about  6  feet  above  the  remainder  of  the 
quarry  is  glaciated  not  only  on  the  upper  surface  and  nearly  vertical  front, 
but  also  beneath  one  of  the  lower  layers,  its  dipping  imder  surface  being 
smoothly  polished  for  about  18  inches  back  from  the  front  of  the  ledge.     A 


Fig.  2. — Glaciated  surface  iu  bed  of  Chicago  drainage  canal.     [Drawing  from  a  photograph  taken  by  Chicago  Drainage 

Commission.] 

photograph  of  this  ledge  has  been  furnished  by  the  Chicago  Academy  of 
Sciences  (see  PL.  XVI). 

A  glaciated  surface  exposed  near  Lemont  in  the  excavation  of  the 
Chicago  drainage  canal  is  represented  in  fig.  2,  which  has  been  drawn  from 
a  photograph  taken  Ijy  the  Chicago  Drainage  Commission.  The  fuiTows 
are  remarkably  direct  for  a  distance  of  several  rods,  and  the  planing  is 
exceptionally  smooth. 

In  the  vicinity  of  T^eniont  the  bed  of  the  Chicago  Outlet  is  extensivelv 
clianneled  by  nearh'  parallel  grooves  several  inches  in  width  and  depth  and 


STEI.E  WITHIN  LIMITS  OF  SHELBTVILLE  MOEAINE. 


417 


many  rods  in  length.     A  photograph  of  an  exposure  made  in  the  diversion 
channel  of  the  Des  Plaines  is  here  furnished  through  the  kindness  of  the 


Fig.  3.— Grooves  exposed  by  canal  in  bed  of  Chicago  Outlet  near  Lemont,  Illinois,  apparently  due  to  abrasion  by 
pebbles  transported  by  water  in  the  outlet  rather  than  to  glaciation.  [Drawing  from  a  photograph  by  Chicago  Drainage 
Commission.] 

Chicago  Drainage  Commission  (see  fig.  3).     These  channels  were  announced 
in  the  Chicago  newspapers  to  be  glacial  grooves,  but  thej^  are  aj)parently 
due  to  water  abrasion  rather  than  glacial  scoring. 
MON  xxsviii 27 


OHAPTERXI. 

THE  CHICAGO  OUTLET  AND  BEACHES  OF  LAKE  CHICAGO. 

PREVIOUS    WRITERS. 

It  is  perhaps  impossible  to  determine  who  was  the  first  person  to  recog- 
nize the  evidence  or  form  the  conception  of  a  southwestward  outlet  from  the 
Lake  Michigan  Basin  to  the  Des  Plaines  Valley.  Inquirj^  among  the  old 
residents  of  this  region  shows  that  many  of  them  recognized  the  beaches  as 
prodiicts  of  the  lake,  and  they  also  noted  that  the  lake  once  discharged  into 
the  Des  Plaines  Valley.  Evidently  these  conceptions  were  entertained  for 
many  years  before  any  notice  appeared  in  scientific  publications. 

Bannister. — Probably  the  earliest  scientific  account  of  the  outlet  is  that 
given  by  Dr.  H.  M.  Bannister,  in  1868,  in  the  Geology  of  Illinois.^  How- 
ever, a  report  by  the  U.  S.  Army  Engineers  upon  the  survey  of  the  Illinois 
River,  by  Col.  James  H.  Wilson  and  William  Gooding,  was  published  the 
same  year,  which  makes  reference  to  the  former  southwestward  discharge 
of  Lake  Michigan.  Dr.  Bannister  opens  his  discussion  of  the  old  lake  outlet 
and  the  raised  beaches  with  the  following  statement: 

It  is  evident  with  a  very  little  observation  that,  at  a  comparatively  recent  period, 
subsequent  to  the  Glacial  epoch,  a  considerable  portion  of  Cook  County  was  under  the 
waters  of  Lake  Michigan,  which  at  that  time  found  an  outlet  into  the  Mississippi 
Valley  through  the  present  channel  of  the  Des  Plaines. 

Andrews. — (.)ne  of  tlie  early  publications  of  the  Chicago  Academy  of 
Sciences  presents  a  discussion  of  the  beaches  by  Dr.  Edmund  Andi'ews, 
which  has  attracted  wide  notice.-  The  ])aper,  however,  deals  mainly  with 
the  work  of  the  lake  at  its  present  stage.     The  ancient  beaches  are  briefly 

'  Geol.  of  Illinois,  Vol.  Ill,  1868,  \>V-  -''10-242. 

-Tlie  North  Americau  lakes  considered  as  elironoiiietei's  of  post-GIacial  time,  by  Dr.  Edmund 
Andrews:  Trans.  Cliicigo  Academy  of  Scieuees,  Vol.  II,  1870,  article  1,  p]).  l-L'4. 

418 


THE  CHICAGO  OUTLET.  419 

discussed,  but  the  outlet  is  not  described.  A  map  accompanying  the  paper 
shows  the  approximate  extent  of  the  old  lake  beyond  its  present  limits  from 
the  southern  end  northward  some  distance  into  Wisconsin  and  Michigan. 

chamberiin. — Prof  T.  C.  CliamberKn  presented  a  brief  discussion  of  the 
beaches  along  the  "Wisconsin  shore  of  Lake  Michigan  in  the  Greology  of 
Wisconsin,^  which  includes  many  important  data  concerning  the  shore 
j)henomena  and  an  interpretation  of  the  lake  history.  In  the  twenty  years 
which  have  elapsed  since  that  report  was  published,  the  studies  of  the  shores 
of  the  Grreat  Lakes  have  brought  out  a  more  complex  history  than  had 
been  anticipated;  hence  the  interpretation  does  not  fully  meet  the  case, 
though  it  recognizes  important  fluctuations  of  lake  level. 

Leverett. — Although,  subscqueut  to  the  publications  just  noted,  there  have 
been  frequent  references  in  geological  literature  to  the  southwestward  outlet 
and  the  ancient  beaches,  no  publication  especially  devoted  to  them  appeared 
until  1888,  when  a  paper  was  published  by  the  present  writer  in  the  Trans- 
actions of  the  Wisconsin  Academy  of  Sciences.^  This  paper  gives  a 
somewhat  detailed  account  of  each  of  the  several  beaches  found  south  of 
latitude  42°  30',  the  latitude  of  the  hue  of  Wisconsin  and  Illinois.  It 
contains  but  a  brief  reference  to  the  outlet.^ 

cooiey. — Prof.  L.  E.  Cooley,  consulting  engineer  of  the  Chicago  Drain- 
age Commission,  has  published  two  papers  which  deal  to  some  extent  with 
the  Chicago  Outlet.*  The  first  paper  discusses  the  outlet  as  a  means  for 
improving  the  sanitary  conditions  at  Chicago.  The  second  paper  deals 
with  it  as  an  important  line  for  navigation,  and  discusses  the  proper  means 
for  obtaining  the  best  results  This  paper  contains  a  large  amount  of  valu- 
able data  concerning  the  regimen  of  the  Illinois  and  Des  Plaines  rivers. 

Marshall. — The  report  of  the  United  States  Army  Engineers  for  1890 
contains  much  valuable  material  collected  by  Capt.  W.  L.  Marshall  con- 
cerning the  Chicago  Outlet  as  a  channel  for  navigation;  also  references  to 
earlier  work  by  that  organization. 


'Geology  of  Wisconsin,  Vol.  II,  1877,  pp.  219*-233. 

-The  raised  beaches  at  the  head  of  Lalie  Michigan,  by  Frank  Leverett:  Trans,  of  Wisconsin 
Acad,  of  Sciences,  Vol.  VII,  1883-1887,  pp.  177-192.     Published  in  1888. 

^  It  should  be  explained  that  the  numerous  typographical  errors  in  the  paper  are  due  to  the  fact 
that  the  writer  had  no  opportunity  to  correct  the  proof. 

■"  Water  supplies  of  Illinois  in  relation  to  health  :  Report  of  the  Illinois  State  Board  of  Health, 
1889.     Lake  and  Gulf  Waterway.     Private  publication,  1891. 


420  THE  ILLINOIS  GLACIAL  LOBE. 

Taylor. — Ml'.  F.  B.  Tavloi"  lias  published  in  the  American  Geologist  obser- 
vations on  liig'li  beaches  in  the  northern  poition  of  the  basin  of  Lake  Michi- 
gan.^ These  beaches,  he  thinks,  pass  beneath  the  present  lake  level  before 
reaching  the  southern  end  of  the  basin.  This  being  the  case,  they  have  no 
connection  with  the  outlet  under  discussion. 

Davis. — Prof  W.  M.  Davis  has  published  a  description  of  the  Chicag-o 
Outlet  in  the  Popular  Science  Monthly."  His  paper  was  based  upon  a  per- 
sonal inspection  of  the  channel  with  the  United  States  topographic  sheets 
in  hand,  and  is  a  very  clear,  though  brief,  discussion  of  the  features. 

THE    CHICAGO    C)lTTt,ET.' 

The  name  ' '  Chicago  Outlet "  has  come  into  use  by  geologists  and  engi- 
neers, without  definite  announcement  or  conference  among  writers,  to  desig- 
nate the  line  of  southwestward  discharge  from  the  basin  of  Lake  Michigan 
across  the  low  divides  near  Chicago  and  thence  down  the  Des  Plaines  and 
Illinois  to  the  Mississippi.  It  may  appropriately  embrace  both  points  of 
discharge  from  the  lake  to  the  Des  Plaines — namely,  the  one  entering  at 
Summit  and  the  one  at  Sag  Bridge. 

When  the  lake  was  occupying  the  highest  beach,  the  north  or  maiil 
outlet  was  entered  about  3  miles  southwest  of  Summit;  when  occupying 
the  second  beach,  the  outlet  was  entered  at  Summit;  when  occupying  the 
third  beach,  the  point  of  entrance  appears  to  have  been  transferred  eastward 
nearly  to  the  present  shore  of  Lake  Michigan,  as  explained  below.  Simi- 
larly the  southern  outlet  was  lengthened  eastward  with  the  lowering  of  the 
lake,  the  point  of  entrance  at  the  time  of  the  highest  beach  being  about  5 
miles  east  of  Sag  Bridge,  at  the  time  of  the  second  beach  near  Blue  Island, 
and  at  the  time  of  the  third  beach  at  Riverdale.  This  relationship  of  the 
several  beaches  to  the  outlets  and  the  eastward  lengthening  of  the  outlets 
may  be  readily  understood  by  a  glance  at  the  accompanying  map  (PI.  XVII). 

There  have  been  several  surveys  which  have  contributed  contour  maps 
of  portions  of  the  Chicago  Outlet  and  of  the  plain  covered  by  the  lake  in 
the  vicinity  of  Chicago.  The  Chicago  Drainage  Commission  have  prepared 
an  excellent  map  with  5-foot  contours  which  covers  nearly  all  of  Cook 


'  American  Geologist,  Vol.  XIII,  May,  1894. 

^Tlie  aucieut  outlet  of  Micliigaii,  by  Prof.  W.  M.  Bavis:  Pojuilar  Science  Monthly,  December, 
1894,  pp.  218-229. 


U.S.  GEOLOGICAL    SURVEY. 


MONOGRAPH    X  X  X  V  I  1  I  PL.  XVH 


LIST  OF  CITIES  AND  VILLAGES. 


GLACIAL  MAP  OF  CHICAGO 
AND  VICINITY. 

By  Fbank  Leyekett. 
1897. 


NOTE. — The  topography  ia  indicated  by 
brofeen  profiles,  the  straight  lines  represent- 
ing plains,  and  the  curved  lines  rolling 
country.  With  the  exception  of  dimes  and 
sandy  beaches  on  the  border  of  Late  Michi- 
gan the  rolling  siirface  represents  moralnic 
topography. 


1  WaukegaD 

2  Gurnee 

3  Hainesville 

4  Fort  Hill 
6  Volo 

6  Wauconda 

7  Fremont 
e Ivanhoe 

9  Diamond  Lake 

10  LibertyvIUe 

11  Kondout 

12  LaVe  Forest 

13  Highland 
U  Ravin  ia 

15  Deerfleld 

16  HalfDayP.  O. 

17  I>ake  Zurich 

18  Barriutrton 

19  Palatine 

20  ArlinEtonHolKhtB 

21  Wheeline 

22  NorthfleW 

23  Oak  Glen 

24  Glencoe 

25  "Winnetka 

26  Wilmette 

27  Evanston 

28  Miles 

29  Park  Ridge 

30  Des  Plalnes 

31  Mount  Prospect 

52  Sebaumberg 

33  Eartlett 

34  Spaulding 

35  Wayne 

36  Ontario 

37  Boselle 
36  Itasca 

39  Eensonvllle 

40  Tamer  Park 

41  Austin 

12  Oak  Park 

43  Riverside 

44  May  wood 

45  Elmhurst 
4fi  Lombard 

47  GrlenEllyn 

48  Wheaton 

49  Turner  .lunotion 
soEola 

61  Naperville 

62  Downers  Grove 
ft3  Hinsdale 

54  Western  Springs 

55  La  Grange 

56  Willow  Springs 

57  Summit 

53  Morgan  Park 

59  Bine  Island 

60  Worth 

61  Sag  Bridge 

62  Lemont 

63  Komeo 

64  Plainfleld 

66  Lock  port 
ee  Hadley 

67  Orland 

68  Bremen 

69  Homewood 

70  Harvey 

71  Thornton 

72  Hammond 

73  Whiting 

74  Gibson 

75  Hessvilie 

76  Griffltb 

77  Edgemoor 
73  Clark 

79  Miller 

80  Wilson's 

81  Hobart 

82  Wheeler 

83  Crown  Point 

84  ShermerviUe 

85  St.  John 

86  BrUDSwiek 


I  Fi  HE  t  nAdt-  I  ^' •"'"  R^'3g\'  T  'R-I.4-E:.  isi5ek.r6wl' " 'r'Tw       '~ 


TOPOGffAPHr  OEL.erW^At-a. 


THE  CHICAGO  OUTLET.  421 

County,  and  the  immediate  borders  of  the  Chicago  Outlet  along  the  Des 
Plaines  River.  This  has  not  been  published,  being  merely  a  study  map. 
The  topographic  work  carried  on  by  the  United  States  Geological  Survey 
in  this  region  is  largely  published.  The  peculiar  features  of  the  upper  por- 
tion of  the  outlet  are  brought  out  in  an  effective  manner  by  the  following 
sheets,  ^n.z,  the  Chicago,  Riverside,  Calumet,  Des  Plaines,  Joliet,  Wilming- 
ton, Monis,  Ottawa,  Marseilles,  Lasalle,  Hennepin,  and  Lacon  sheets. 
These  sheets  cover  something  over  100. miles  of  the  former  lake  outlet,  or 
nearly  one-third  the  distance  from  the  head  of  the  outlet  to  the  Mississippi. 
The  remainder  of  the  outlet  is  shown  in  Prof  C.  W.  Rolfe's  map  sheets,  yet 
unpublished.  The  reduced  contour  map  (PL  III)  accompau3:'ing  this  report 
is  based  upon  these  several  surveys.  It  serves  to  indicate  the  comparative 
size  of  the  valleys  occupied  by  the  outlet  and  of  the  main  tributaries  of  the 
Illinois.  But  to  fully  appreciate  the  features  produced  by  the  outlet,  refer- 
ence should  be  made  to  the  lai'ge  scale  maps  just  mentioned. 

In  the  interpretation  of  these  features  from  the  maps,  care  must  be 
exercised  in  determining  the  condition  of  the  valley  at  the  time  the  outlet 
first  became  operative.  The  portion  of  the  Illinois  below  Hennepin,  it  will 
be  observed,  is  a  preglacial  valley,  and  was  only  partially  filled  by  the  glacial 
deposits.  This  filling  is  preserved  in  terraces  along  the  borders  of  the 
valley.  The  glacial  terraces  seldom  rise  to  a  height  of  more  than  100  feet 
and  in  the  lower  100  miles  their  average  height  scarcely  exceeds  50  feet 
above  the  present  sti-eam.  In  the  portion  of  the  valley  above  Hennepin 
the  stream  is  mainly  in  a  glacial  or  postglacial  course,  but  even  here  there 
are  complications  which  make  it  no  easy  matter  to  determine  the  amount 
of  erosion  attributable  to  the  outlet.  Before  the  accession  of  the  lake 
waters  this  valley  was  the  line  of  discharge  for  streams  issuing  from  the 
ice  sheet,  as  possibly  of  interglacial  streams,  some  evidence  of  which  has 
been  gathered  both  by  Professor  Chamberlin  and  the  writer.  Although 
the  streams  were  generally  so  heavily  charged  with  detritus  as  to  build  up 
rather  than  erode  their  beds  for  some  distance  below  the  point  of  emergence 
from  the  ice  sheet,  it  seems  scarcely  probable  that  filling  would  have 
exceeded  erosion  tlu-oughout  the  entire  length  of  the. Des  Plaines  and 
Illinois  valleys.  The  basin  at  the  head  of  the  Illinois,  as  noted  above,  was 
apparently  occupied  by  a  lake  at  the  Valparaiso  substage  of  glaciation,  and 
this  would  have  received  the  greater  part  of  the  detritus  borne  down  by  the 


422  THE  ILLINOIS  GLACIAL  LOBE. 

glacial  floods  on  the  Des  Plaines  and  other  tributaries  entering  the  basin 
farther  east,  thus  permitting  the  water  to  issue  at  the  western  end  of  the 
basin,  unburdened  with  glacial  material.  The  stream  discharging  westward 
from  this  basin  would,  therefore,  have  a  tendency  to  deepen  the  new  valley 
opened  across  the  Marseilles  moraine,  and  in  all  probabilit}'  would  have 
extended  its  excavation  at  least  through  the  new  portion  of  the  valley  to 
Hemiepin,  there  being  in  that  section  a  gradient  of  several  inches  per  mile 
and  possibly  at  first  a  higher  gradient.  It  seems  not  improbable,  also,  that 
some  excavation  was  accomplished  by  the  glacial  floods  in  their  passage 
over  the  terraces  in  the  lower  portion  of  the  Illinois  Valley,  the  advantages 
for  erosion  being  as  good  for  these  floods  as  for  the  later  ones  fed  by  Lake 
Chicago. 

It  is  also  necessary  to  estimate  the  amount  of  filling  which  the  lower 
course  of  the  outlet  has  received  since  the  lake  waters  were  withdrawn. 
Concerning  this  filling.  Prof  L.  E.  Cooley  has  made  some  investigation  and 
concludes  that  from  Peru  to  Peoria  it  will  average  30  feet,  and  is  appreciable 
to  the  mouth  of  the  Illinois,  though  probably  somewhat  less  toward  the 
mouth  of  the  river.^ 

In  the  Des  Plaines  Valley  the  erosion  of  the  Valparaiso  moraine  and 
of  the  tei-races  outside  of  it  was  probably  very  largely  effected  by  the  lake 
waters.  An  examination  of  this  portion  of  the  outlet  will  therefore  be  likely 
to  afford  a  fair  understanding  of  the  size  of  the  channel  which  it  formed. 

From  the  topographic  maps  it  appears  that  the  bed  of  the  lake  outlet 
declines  from  about  51^)0  feet  at  Lemont,  in  the  midst  of  the  Valparaiso 
system,  to  scarcely  500  feet  at  the  head  of  the  Illinois,  or  90  feet  in  a 
distance  of  25  miles.  Of  this  fall,  76  feet  is  made  in  a  little  less  than  10 
miles,  from  Romeo  to  Joliet  pool.  The  glacial  terraces  which  border  the 
outlet  decline  from  about  630  feet  to  570  feet  between  Lemont  and  the  liead 
of  the  Illinois.  This  deepening  of  the  channel  is  shown  by  the  maps  to  be 
somewhat  irregular,  ranging  from  40  feet  to  about  70  feet,  but  an  average 
erosion  of  50  feet  ma}'  be  assumed.  This  deepening  embraces  not  only 
the  work  at  the  time  the  upper  beach  was  forming,  but  also  that  carried  on 
during  tlie  tonuation  of  tlie  second  and  tliird  beaches,  or  down  to  the  time 
of  the  final  abandonment  of  tlic  lake  outlet.     Tlic  chamiel  above  Joliet  has 


'  Couiuiiuiiciitcd  to  tliu  writer. 


THE  CHICAGO  OUTLET.  423 

a  breadth  of  1  to  IJ  miles,  averaging  perhaps  1^  miles.  Between  Joliet 
and  the  head  of  the  Illinois  several  island-like  remnants  of  the  glacial 
terraces  are  preserved  in  the  midst  of  the  channel,  making  it  more  difficult 
to  estimate  the  Ijreadth,  but  it  is  not  markedly  greater  than  in  the  portion 
above  Joliet.  The  portion  above  Joliet  is  cut  to  a  slight  depth  into  the 
Lockport  (Niagara)  limestone,  which  there  underlies  the  glacial  gravel.  The 
excavation  in  limestone,  however,  amounts  to  not  more  than  one-fourth  the 
size  of  the  channel,  for  the  limestone  seldom  rises  more  than  40  feet  above 
the  bed  of  the  lake  outlet,  and  in  many  places  its  surface  comes  down  nearly 
to  the  level  of  the  valley  floor.  Below  Joliet  there  was  even  less  excava- 
tion in  the  rock  than  above.  It  is  estimated  that  the  rock  excavation  there 
does  not  exceed  10  per  cent  of  the  total  cutting. 

In  the  low  tract  at  the  head  of  the  Illinois  (the  Morris  Basin)  the  depth 
of  the  excavation  by  the  outlet  is  very  slight,  averaging  ]3robably  less  than 
20  feet  in  the  10  miles  between  the  head  of  the  Illinois  and  Morris.  The 
plain  appears  to  have  descended  nearly  to  the  520-foot  contour  on  the 
borders  of  the  river  before  modified  at  all  by  lake  or  stream  action.  A  low 
bluff  formed  on  the  north  border  of  the  basin  has  a  height  of  15  to  20  feet. 
On  the  south  border  there  is  no  bluff,  that  side  of  the  basin  being  heavily 
coated  with  sand  deposits.  These  deposits  may  perhaps  have  been  laid 
down  in  part  at  the  time  the  lake  waters  were  forming  the  outlet,  but  they 
are  probably  largely  of  earlier  date.  In  this  basin  the  lake  outlet  has  an 
average  width  of  4  or  5  miles. 

In  the  section  of  the  Illinois  immediately  below  (west  from)  this  basin, 
erosion  prior  to  the  opening  of  the  Chicago  Outlet  jJi'obably  had  brought 
the  level  of  the  valley  bottom  down  to  that  of  the  upper  beach  line  of  the 
basin,  550  to  560  feet  above  tide.  The  bed  of  the  Chicago  Outlet  is  nearlj^ 
500  feet,  thus  leaving  about  60  feet  subsequent  depth  of  erosion.  Passing 
westward  the  broad  bed  of  the  Chicago  Outlet  declines  nearl}-  60  feet  in  the 
40  miles  between  the  west  border  of  the  basin,  just  mentioned,  and  the  bend 
of  the  Illinois  near  Hennepin.  Whether  the  valley  had  the  same  gradient 
at  the  time  the  accession  of  lake  waters  occurred  is  not  known,  but  it  could 
not  have  been  greatly  diflFerent,  for  the  glacial  terrace  just  above  Hennepin 
stands  about  30  feet  lower  than  the  beach  lines  of  the  Morris  Basin,  and  this 
terrace  in  all  probability  had  been  eroded  the  remaining  30  to  40  feet  neces- 
sary to  give  a  similar  gradient. 


424  THE  ILLINOIS  GLACIAL  LOBE. 

The  width  of  the  outlet  between  Mon-is  and  Hennepin  averages  about 
IJ  miles.  The  excavation  is  largely  in  soft  St.  Peter  sandstone,  there  being 
nearly  continuous  rock  bluffs  to  a  height  of  60  to  75  feet  above  the  level  of 
the  bed  of  the  outlet.  This  sandstone  and  the  Coal  Measures  sandstone 
which  in  places  overlies  it  present  much  less  resistance  to  sti'eam  action  than 
the  tirni  Loekport  (Niagara)  limestone.  The  resistance  may  not  be  markedly 
gi-eater  than  that  of  the  beds  of  glacial  drift. 

As  noted  above,  the  level  at  which  excavation  by  lake  waters  began  in 
the  section  below  the  great  bend  of  the  Illinois  is  less  than  1 00  feet  above 
the  present  stream,  since  the  glacial  terraces  in  which  the  lake  outlet  was 
excavated  seldom  reach  a  level  100  feet  above  the  bed  of  the  outlet,  while 
below  the  mouth  of  the  Sangamon  they  rise  scarcely  50  feet  above  that 
level.  If  the  30  feet  of  filling  estimated  by  Professor  Cooley  be  added,  it 
seems  a  liberal  estimate  to  allow  75  feet  of  average  excavation  in  this  lower 
section  of  200  miles.  It  may  not  have  been  more  than  two-thirds  that 
amount.  The  width  of  the  outlet  in  this  lower  section  ranges  from  2  up  to 
about  5  miles,  with  an  average  of  perhaps  3  miles.  This  excavation  is  in  a 
loose,  easil}^  eroded  bed  of  sand  and  fine  gravel,  which  had  been  deposited 
largely  by  glacial  streams. 

Summing  up  the  above  estimates,  it  appears  that  the  outlet  has  a  width 
ranging  from  1  mile  up  to  about  5  miles,  and  a  depth  ranging  from  20  feet 
up  to  70  feet.  Its  length  from  Summit  to  the  mouth  of  the  Illinois  is  300 
miles.  The  excavation  is  probably  not  less  than  3  cubic  miles.  With  the 
exception  of  about  15  miles  between  Lemont  and  Joliet  and  40  miles 
between  Morris  and  Peru,  where  rock  strata  have  been  eroded,  the  excava- 
tion is  almost  entirely  in  beds  of  drift.  The  width  varies  -with  the  resist- 
ance to  erosion,  being  least  in  the  section  where  the  resistant  limestone  was 
eroded  and  greatest  where  there  were  only  drift  beds  to  remove,  while  in 
the  sandstone  the  channel  is  of  intermediate  breadth.  The  breadth  is  also 
to  some  degree  dependent  upon  the  slope  of  the  bed,  being  narrower  in  the 
portions  with  rapid  fall  than  in  portions  having  a  low  rate  of  descent. 

Throng]  lout  the  entire  length  of  the  outlet  the  bluffs  are  steep,  like  a 
river  bank,  and  deposits  made  by  side  streams  on  the  edge  of  the  valley 
are  very  meager — ii  feature  which  indicates  that  the  stream  had  great  vol- 
ume, probably  filling  the  channel  from  bluff  to  bluff,  and  a  current  suffi- 


THE  CHICAGO  OUTLET.  425 

ciently  strong  to  cany  away  nearly  all  the  detritus  brought  into  it  by  the 
side  streams 

The  rapids  between  Romeo  and  Joliet  occur  in  a  section  where  the 
limestone  is  friable,  and  it  is  thought  b}'  Professor  Cooley  that  the  friability 
is  such  that  falls  could  not  have  been  maintained,  or  even  established.  The 
removal  of  the  existing  rapids,  the  main  barrier  in  the  course  of  the  outlet, 
it  is  estimated,  would  require  the  excavation  of  a  channel  in  rock  only 
about  20  miles  in  length  and  26  to  75  feet  in  depth.  This  excavation 
would  be  about  ten  times  that  accomplished  by  the  lake  outlet  in  that  part 
of  its  course.  Being  the  outlet  from  a  lake,  the  amount  of  sediment  carried 
by  its  waters  is  a  matter  which  should  be  weighed  in  discussing  the  slight 
amount  of  excavation. 

Professor  Cooley  has  called  the  writer's  attention  to  the  deposits  at  the 
head  of  Lake  St.  Clair  as  likely  to  furnish  an  index  of  the  amount  of  sedi- 
ment transported  by  the  Chicago  Outlet.  A  delta  with  an  area  of  several 
square  miles  .has  been  built  in  the  head  of  Lake  St.  Clair,  which  must  have 
derived  the  bulk  of  its  material  from  southward-moving  littoral  currents 
along  both  the  borders  of  Lake  Huron.  In  the  lake  under  discussion  littoral 
currents  along  the  west  border  would  have  transported  material  probably  in 
as  great  volume  as  on  either  shore  of  Lake  Huron,  but  those  on  the  east  and 
south  may  have  contributed  less,  for  wind  drifting  there  is  very  effective. 
It  seems  legitimate  to  assume  that  at  least  half  as  much  sediment  was  being 
transported  down  the  Chicago  Outlet  as  is  carried  by  the  St.  Clair  River. 
From  this  it  appears  probable  that  the  waters  of  the  Chicago  Outlet  were 
somewhat  less  turbid  than  the  St.  Clair.  Professor  Cooley  thinks  the 
contributions  of  sediment  to  the  outlet  through  the  Des  Plaines  were  of 
little  consequence,  for  this  river  has,  since  the  lake  waters  were  withdrawn, 
made  scarcely  any  filling  of  the  outlet  below  Riverside,  where  its  delta 
would  naturally  accumulate.  The  accession  of  larger  tributaries  below 
may  have  rendered  the  stream  slightly  more  turbid  than  on  the  rapids 

It  should  not  be  inferred  that  this  outlet  is  entirely  free  from  river 
debris.  Beginning  at  the  upper  beach,  near  Summit,  there  is  for  several 
miles  a  mass  of  coarse  material,  largely  limestone  blocks,  too  large  to  have 
been  transported  by  the  current,  covering  the  bed  of  the  outlet.  The 
Drainage  Canal  exposes  excellent  sections  of  the  coarse  river  ddbris  from 
Summit  to  Lemont,  there  being'  only  limited  areas  in  this  interval  where 


426  THE  ILLINOIS  GLACIAL  LOBE. 

the  solid  rock  comes  to  the  siu-face.  Below  Lemont  the  bare  I'ock  forms 
much  of  the  floor  as  far  as  Joliet.  From  Joliet  to  the  head  of  the  Illinois 
perhaps  half  the  floor  is  covered  with  deposits  of  drift  and  river  deVjris,  so 
that  the  distance  to  rock  is  not  known.  The  remainder  is  either  bare  rock 
or  rock  with  a  very  thin  deposit  of  coarse  river  debris,  with  a  liberal  sup- 
ply of  bowlders  of  Canadian  derivation.  In  the  ^Morris  Basin  the  rock  is 
largely  shale.  This  has  been  eroded  in  places  by  the  current,  and  the  hol- 
lows have  been  tilled  with  sand.  From  the  Morris  Basin  to  the  bend  of 
the  Illinois  the  rock  floor,  mainly  sandstone,  is  generally  swept  clean.  The 
St.  Peter  sandstone  of  this  section  is  of  such  a  texture  as  to  break  up  rap- 
idly into  its  constituent  grains,  and  these,  as  fast  as  they  were  set  free, 
would  have  been  carried  by  the  strong  current  down  to  the  lower  Illinois, 
and  probably  on  into  the  Mississippi.  The  lower  Illinois  has  onlv  sand  and 
silt  in  its  bottoms.  This  section  is  now  in  process  of  silting  up,  the  current 
being  too  slugg'ish  to  carry  away  the  material  brought  in  fi'om  the  upper 
portion  of  the  stream. 

Accumulations  of  bowlders  should  be  mentioned  in  connection  with 
the  river  debris.  The  most  conspicuous  accumulation  noted  is  that  on  the 
borders  of  the  Sag  outlet,  just  east  of  the  point  where  it  enters  the  ^'alpa- 
raiso  morainic  system  and  northeast  of  the  village  of  Worth.  An  area  of 
perhaps  a  square  mile  is  so  thickly  strewn  that  one  might  almost  step  from 
stone  to  stone  over  its  entire  extent.  There  are,  it  is  estimated,  more  than 
i,000  bowlders  per  acre.  Surface  bowlders  are  not  rare  in  otlier  portions  of 
the  old  lake  bottom  where  sand  deposits  are  thin  or  wanting-,  there  being, 
perhaps,  200  per  square  mile  on  the  part  of  the  lake  bottom  where  till  is 
exposed.  There  seems,  however,  to  l)e  a  tendency  to  aggregation  at  the 
entrance  to  the  old  outlets.  This  feature  sug-gests  that  floating  ice  has  been 
influential  in  their  distribution,  though  there  mav  have  been  a  large  number 
brought  by  the  ice  sheet,  the  head  of  the  outlets  being  near  the  inner  border 
of  the  Valparaiso  morainic  system. 

Some  very  large  bowlders  have  been  fcund  along  the  Drainage  Canal. 
The  large  ones  occur  in  most  abundance  where  the  Valparaiso  system  is 
crossed  by  tlie  lake  outlet.  Bowlders  are  also  very  numerous  for  a  few 
miles  above  the  junction  of  the  Des  Plaines  with  tlie  Kankakee.  They  seldom 
reach  tlie  large  size  which  bowlders  in  the  Valparaiso  svstem  present. 


THE  ILLINOIS  GLACIAL  LOBE.  427 


THE  GliACIAIi  LAKE   CHICAGO. 


The  uame  "Lake  Chicago"  was  introduced  by  the  writer  in  a  recent 
bulletin  issued  by  the  Chicago  Academy  of  Sciences.-^  The  need  for  a 
name  for  this  glacial  lake  and  the  reason  for  the  selection  of  this  name  are 
set  forth  in  the  following  statement:  - 

The  introduction  of  the  name  "  Lake  Chicago"  for  the  glacial  lake  which  was  held 
in  the  southern  end  of  the  Lake  Michigan  Basin  seems  convenient,  if  not  necessary, 
inasmuch  as  its  area  was  not  coincident  with  that  of  Lake  Michigan  and  its  outlet 
was  in  the  reverse  direction.  It  is  also  in  keeping  with  the  custom  of  students  of 
glacial  lakes,  who  find  it  advantageous  to  employ  a  special  name  for  each  of  the 
temporary  bodies  of  water  in  the  several  basins.  The  name  "Lake  Chicago"  seems 
especially  pertinent,  since  the  glacial  lake  extended  about  as  far  beyond  the  present 
limits  of  Lake  Michigan  in  the  vicinity  of  Chicago  as  fit  any  part  of  its  border.  It  is 
also  a  name  which  readily  suggests  the  position  of  the  lake,  and  it  is  in  keeping  with 
the  name  which  has  conu^  into  use  for  the  outlet,  namely,  the  "Chicago  Outlet." 

The  name  "  Lake  Chicago  "  is  a))i)Ued  provisionally  to  all  the  stages  at  which 
there  was  a  southwestward  outlet,  but  it  is  not  yet  certain  whether  they  were  all 
formed  during  the  occupancy  of  a  portion  of  the  Lake  Michigan  Basin  by  the  ice  sheet. 

The  precise  relations  of  these  beaches  to  the  ice  sheet,  or  points  of 
connection  with  it,  have  not  as  yet  been  determined.  The  writer's  study 
has  been  carried  no  farther  north  than  to  the  line  of  Wisconsin  and  Illinois 
on  the  west  side  and  to  Grrand  River  on  the  east  side  of  Lake  Michigan. 
Professor  Chamberlin's  studies  left  the  precise  extent  of  the  higher  beaches 
undetermined.  Mr.  Taylor's  observations  have  been  confined  to  the  north- 
ern portion  of  the  basin,  and  as  yet  no  one  has  examined  the  intervening 
districts,  whei'e  it  appears  probable  that  the  higher  beaches  terminate. 
Probably  the  most  favorable  field  for  investigation  will  be  found  on  the 
Wisconsin  side,  since  extensive  deposits  of  wind-drifted  sand  on  the  border 
of  the  lake  in  Michigan  make  it  difficult  to  determine  the  extent  of  water 
action.  The  long  stretches  of  high  bluff,  however,  interrupt  the  beaches  so 
greatly  that  some  difficulty  is  anticipated  in  making  precise  correlations  on 
the  Wisconsin  side. 

Enough  is  known  to  make  certain  that  the  general  direction  of  retreat 
of  the  ice  sheet  was  northeastward.  The  southern  and  western  jjortions  of 
the  Great  Lake  basins  were,  therefore,  the  first  to  become  free  from  ice  and 

'  The  Pleistocene  features  and  deposits  of  the  Cliicago  area,  by  Frank  Leverett :  Bull.  No.  2, 
Geo),  and  Nat.  Hist.  Survey,  Chicago  Academy  of  Sciences.     Issued  May,  1897. 
"Op.  cit.,  p.  65. 


42r<  THE  ILLINOIS  (iLAGlAL  LOBE. 

to  be  occupied  by  glacial  lakes.  While  the  ice  sheet  was  covering  the 
present  outlets  of  Lakes  Superior  and  Michigan,  these  lakes  had  no  connec- 
tion with  each  other,  nor  with  the  lakes  to  the  east,  and  their  discharge  was 
southward  or  southwestward  into^the  Mississippi,  from  the  present  heads  of 
these  lakes.  A  small  district  west  of  Lake  Erie  was  also  occupied  by  a 
lake  that  discharged  southwestward  to  the  Wabash.  Upon  the  withdrawal 
of  the  ice  sheet  from  the  southern  peninsula  of  Michigan  and  the  southern 
portion  of  the  Lake  Huron  Basin,  the  lake  at  the  western  end  of  Lake  Erie 
became  expanded  and  a  line  of  discharge  was  opened  eventually  from 
Saginaw  Bay  across  the  southern  peninsula  of  Michigan  to  the  Lake  Michi- 
gan Basin,  and  this  being  lower  than  the  outlet  to  the  Wabash,  that  outlet 
was  abandoned.  The  waters  of  the  Lake  Huron  Basin  being  held  at  a 
somewhat  higher  level  than  those  of  the  Lake  Michigan  Basin,  the  flow  of 
water  was  from  the  former  to  the  latter.  The  glacial  lake  which  discharged 
across  the  southern  peninsula  of  Michigan  extended  over  the  district  between 
Lake  Huron  and  Lake  Erie,  as  well  as  the  Lake  Erie  Basin  and  the  low 
district  bordering  it  on  the  south  and  Avest.  It  apparently  did  not  extend 
far  into  the  Ontario  Basin,  as  a  study  of  moraines  indicates  that  the  ice  sheet 
occupied  that  basin  at  the  time  of  this  discharge.  It  thus  appears  that  the 
Chicago  Outlet  at  one  time  was  the  line  of  discharge  for  an  area  much  larger 
than  the  present  Lake  Michigan  Basin. 

Three  well-defined  beaches  have  been  recognized  at  the  southern  end 
of  the  Lake  Michigan  Basin  above  the  level  of  the  present  beach,  which 
are  known  a;s  the  Upper  or  Grlenwood  beach,  the  Second  or  Calumet 
beach,  and  the  Third  or  Tolleston  beach. 

THE  UPPER  OR  GLENWOOD  BEACH. 

This  beach  receives  its  name  from  the  village  of  Grlenwood,  on  the 
Chicago  and  Eastern  Illinois  Railroad,  a  few  miles  south  of  the  limits  of 
Chicago.  The  name  has  been  selected  (1)  because  the  beach  is  especially 
well  developed  at  that  village,  and  (2)  because,  being  near  the  State  line  of 
Indiana  and  Illinois,  the  name  will  be  familiar  to  residents  of  either  State. 

In  the  Illinois  portion  of  Lake  Chicago  this  beach  is  present,  except 
for  a  few  miles  between  Waukegan  and  Winnetka,  where  the  lake  shore  is 
now  fai-ther  west  than  it  was  at  the  time  this  beach  was  formed.  Li 
Indiana  the  beach  is  present  throughout  the  entire  extent  of  the  border  of 


THE  GLACIAL  LAKE  CHICAGO.  429 

Lake  Chicago  in  that  State,  being  nowhere  less  than  2  and  in  places  12 
miles  back  from  the  shore.  In  Michigan  it  is  absent  for  a  short  distance 
at  the  "clay  banks,"  north  of  New  Buffalo,  where  the  present  shore 
stands  farther  east  than  the  shore  of  Lake  Chicago.  It  is  also  absent  for 
the  same  reason  for  a  few  miles  near  the  line  of  Berrien  and  Van  Bnren 
counties,  north  of  St.  Joseph,  Michigan.  Tracing  in  detail  the  course  of 
this  beach  is  as  follows : 

From  the  Wisconsin  line  southward  to  South  Waukegan  it  stands  onh" 
1  to  2  miles  back  from  the  shore  of  Lake  Michigan  and  comes  out  to  that 
shore  at  the  poiut  where  the  bluff  of  till  sets  in  south  of  Waukegan.  This 
bluff  of  till  stands  above  the  highest  lake  level  as  far  south  as  Winnetka. 
From  Winnetka  a  cut  bank,  nearly  20  feet  in  height,  extends  south  along 
the  face  of  the  east  till  ridge  noted  above  to  its  terminus,  perhaps  1  mile 
from  the  point  where  the  old  shore  departs  from  the  present  shore  of  the 
lake.  From  the  terminus  of  this  ridge  a  bar  was  built  out  southwestward 
6  or  6  miles,  terminating  about  a  mile  east  of  Chicago  River,  in  the  west- 
ern part  of  T.  41,  E..  13  E.  The  bar  sends  out  two  prominent  spurs  to  the 
west,  a  distance  of  nearly  1  mile.  These  probably  mark  the  termini  in  its 
early  stages  of  growth.  The  average  width  of  this  bar  is  about  one-fourth 
mile,  and  it  was  built  up  to  a  height  of  10  to  20  feet  above  the  bottom  of 
the  bay  back  of  it.  It  consists  largely  of  gravel,  but  has  a  liberal  admix- 
ture of  sand.  The  bay  back  of  this  bar  extended  to  the  valley  of  the 
Chicago  River  and  has  a  width  of  2  to  3  miles.  The  northern  end  finds  a 
narrow  extension  northward  in  Skokie  Marsh.  The  site  of  this  old  bay  is 
now  largely  luider  cultivation,  though  some  portions  are  still  marshy. 

The  question  naturally  arises  whether  this  accumulation  of  gravel  and 
sand  was  formed  by  the  lake  currents  and  waves  independent  of  the  Chicago 
River,  or  was  largely  formed  as  a  delta  from  that  stream.  This  deposit  is 
not  in  the  form  of  a  delta  built  up  at  the  debouchure  of  the  river  into  the 
lake,  but  lies  some  distance  to  the  east  of  the  river  valley,  thus  indicating 
that  it  was  formed  by  the  lake.  Moreover,  to  make  it  still  more  evident 
that  it  was  the  lake  and  not  the  river  which  contributed  the  great  bulk  of 
the  beach  deposit,  it  is  found  that  the  river  valley  above  the  jjoint  where  it 
entered  the  old  lake  has  very  little  assorted  material,  such  as  would  accu- 
mulate above  a  delta. 


430  THE  ILLINOIS  GLACIAL  LOBE. 

The  beach  appears  on  the  west  side  of  the  Chicag-o  River,  in  sec.  19, 
T.  41,  R.  13  H,  about  a  mile  northwest  from  the  terminus  of  the  bar.  From 
this  ])oint  southward  to  Oak  Park  the  shore  is  usually  a  cut  bank  ranging 
from  6  to  25  feet  in  height,  with  occasional  deposits  of  beach  gravel  and 
sand  along  its  front.  At  Oak  Park  there  is  an  extension  of  gravel  down 
the  east  side  of  the  Des  Plaines  River  similar  to  that  of  the  bar  east  of  the 
Chicago  River  noted  above.  A  ridge  or  bar  20  to  40  rods  in  width  and  10 
feet  or  more  in  lieight  extends  from  Oak  P.a-k  south  about  2  miles  to  the 
south  part  of  sees.  13  and  14,  T.  39,  R.  12  E.,  and  there  terminates  abruptly 
with  a  level  nearly  20  feet  above  the  plain  on  its  immediate  borders. 

Passing  to  the  west  side  of  the  Des  Plaines  River,  the  beach  ajjpears 
about  a  mile  above  the  southern  end  of  the  bar  just  described,  and  passes 
in  a  curving  course  westward  through  the  south  edge  of  Maywood,  in  sees. 
14,  22,  and  16,  T.  39,  R.  12  E.  This  portion  of  the  beach  is  only  2  to  4 
feet  in  height,  and  at  the  west  it  fades  out  completely.  Its  faintness  in  this 
district  is  probably  due,  in  part  at  least,  to  the  protection  from  wave  action 
occasioned  by  the  bar  just  described.  Upon  passing  south  and  crossing 
Salt  Creek,  about  a  mile  from  the  point  where  the  beach  fades  out,  it 
reappears  as  a  well-defined  ridge,  composed  of  sand  and  gravel,  rising  from 
10  to  12  feet  above  the  border  of  the  plain  on  the  east,  and  ha^^ing  a 
breadth  of  30  to  40  rods.  Following-  this  beach  southward,  it  changes  in 
about  a  mile  to  a  cut  bank,  which  is  well  defined  from  that  point  southward 
to  the  lake  outlet,  a  short  distance  south  of  Lagrange.  Its  course  is 
through  the  east  part  of  the  city  of  Lagrange,  where  it  is  in  the  form  of  a 
cut  bank  10  to  15  feet  in  height. 

Passing  to  the  west  side  of  the  outlet,  near  Willow  Springs,  the  shore 
line  is  found  as  a  cut  bank  along  the  east  face  of  the  prominent  morainic 
tract  which  occupies  the  interval  between  the  two  outlets  of  the  lake. 
Though  mainly  a  cut  bank,  the  beach  is  represented  occasionally  bv 
deposits  of  gravel  and  sand. 

South  from  the  southern  or  Sag  outlet,  tlie  shore  is  carved  on  tlie 
inner  face  of  the  Valparaiso  moraine  with  banks  5  to  20  feet  nr  more  in 
height,  but  with  only  occasional  deposits  of  gravel  and  sand.  U])ou 
approaching  the  State  line,  however,  near  Glenwood,  the  shore  bears  away 
from  tlie  mora,ine,  and  deposits  of  gravel  and  sand  are  built  up  to  a  height 
of  6  t<i  12  feet  or  more.     These  are  sometimes  in  the  form  of  a  sinu'le  i-idsre. 


THE  GLACIAL  LAKE  CHIOAGf).  431 

but  not  infrequently  a  series  of  parallel  ridges  occur,  separated  by  narrow 
sags. 

The  effect  of  the  waves  at  this  lake  stage  is  discernible  on  the  borders 
of  Blue  Island  till  ridge,  thoug-h  the  western  border  is  characterized  by 
dunes  which  conceal  to  some  extent  the  action  of  the  lake. 

The  beach  enters  Indiana  near  Dyer  and  passes  eastward  through  the 
center  of  the  village.  It  stands  about  10  feet  above  the  plain  bordering  it 
on  the  nortli  and  is  30  to  40  rods  in  width.  Within  2  miles  east  of  Dyer 
it  reaches  a  height  of  25  or  30  feet,  there  being  wind-drifted  sand  along  its 
crest.  Eastward  from  there  to  a  point  about  1  ^  miles  east  of  Schererville  it 
maintains  a  height  of  20  to  30  feet  and  width  of  40  to  60  rods.  It  then 
curves  toward  the  northeast  and  dies  out  in  less  than  a  mile.  Continua- 
tions are,  however,  found  in  the  district  to  the  north.  About  a  mile  north 
from  its  east  end  a  small  ridge  sets  in,  which  leads  eastward,  passing  south 
of  Griffith.  A  larger  ridge  sets  in  on  the  south  side  of  Cady  Marsh  west  of 
G-riffith  and  leads  eastward  through  that  village.  It  soon  becomes  a  belt  of 
sand  one-half  mile  or  more  in  width,  with  several  parallel  ridges,  and  this 
belt  extends  in  a  course  north  of  east  through  Ross,  Liverpool,  and  Chrisman, 
and  comes  to  Calumet  River  about  2  miles  northeast  of  Chrisman.  The 
Second  or  Calumet  beach  is  closely  associated  with  it  from  the  vicinity  of 
Ross  to  Chrisman.  From  Calumet  River  the  two  beaches  lead  northeastward 
nearly  parallel  with  the  present  shore  of  Lake  Michigan,  and  distant  ^  to  3 
miles  from  it,  to  Trail  Creek  near  Michigan  City,  beyond  which  there  is 
considerable  com23lexit3',  as  shown  below. 

The  belt  of  sandy  ridges  whose  com-se  has  just  been  outlined  appar- 
ently did  not  form  the  extreme  southern  limits  of  Lake  Chicago,  but 
inclosed  or  shut  in  bays  of  considerable  size  on  the  south  border.  One  of 
these  bays  extended  south  into  the  Deep  River  Basin  several  iniles  bevond 
the  sand  belt,  its  south  border  being  2  or  3  miles  south  of  Hobart.  From 
this  bay  there  was  apparently  a  westward  connection  with  the  lake  along 
the  valley  of  Turkey  Creek  between  a  till  ridge  noted  above  and  the  north 
border  of  the  Valparaiso  morainic  system.  In  places  a  cut  bank  3  to  5  feet 
high  has  been  formed  on  the  slopes  of  these  bordering  moraines. 

Another  bay  was  formed  in  the  Salt  Creek  di-ainage  basin,  which 
extended  3  or  4  miles  south  of  the  belt  of  sand  ridges.  This  was  separated 
from  the  bay  in  the  Deej)  River  Basin  by  the  till  ridge  which  leads  north- 


432  THE  ILLINOIS  GLACIAL  LOBE. 

ward  from  near  Wheeler  to  the  soutli  border  of  the  sand  belt  near  Chrisman. 
From  Salt  Creek  Basin  a  bay  or  marsh  extended  up  Calumet  River,  prob- 
ably about  to  the  east  line  of  Porter  County,  a  distance  of  10  miles  or 
more.  Its  connection  with  the  open  lake  appears  to  have  been  along  the 
line  of  Calumet  River.  In  this  bay  and  also  the  one  in  the  Deep  River 
Basin  wave  action  was  not  strong  enough  to  foi-m  continuous  well-defined 
shores,  yet  cut  banks  3  or  4  feet  in  height  were  noted  at  several  places  on 
their- borders,  and  there  is  a  thin  coating  of  sand  over  much  of  the  area 
covered  by  the  bays.  East  of  Hobart  the  sand  presents  low  ridges  5  to  10 
feet  high  and  10  or  12  rods  wide,  trending  nearly  north  to  south.  These 
are  developed  oidy  over  1  or  2  square  miles. 

A  bay  also  occupied  east  and  west  Trail  Creek  valleys  and  connected 
with  the  open  lake  along  the  valley  of  the  main  Trail  Creek.  This  bay 
was  shut  off  from  the  niain  water  by  the  till  ridges  which  follow  the  north 
side  of  these  streams.  Its  outlet  into  the  lake  is  bordered  in  places  b}'  a 
sandv  ridge  running  northward  parallel  with  Trail  Creek.  The  best 
developed  ridge  is  on  the  west  side  of  the  creek,  in  sees.  11,  2,  and  3, 
T.  37,  R.  4  W.,  where  it  has  a  height  of  10  or  12  feet  and  is  maintained  for 
a  distance  of  2  or  3  miles.  There  is  a  deposit  of  sand  several  feet  in  depth 
covering  the  bottom  of  this  bay.  It  may  have  been  derived  in  large  part 
as  a  wash  from  the  steep  bluff-like  border  of  the  Valparaiso  moraine,  which 

lies  immediatelv  south. 
ft  ^ 

From  the  valley  of  Trail  Creek,  near  Michigan  City,  Indiana,  north- 
eastward to  Galien  River  near  New  Buffalo,  Michigan,  a  distance  of  6  or  7 
miles,  it  is  difficult  to  locate  the  upper  beach.  There  are  several  short 
sandy  ridges  separated  by  swamps  and  marshes,  but  not  a  continuous  well- 
defined  belt  of  sand,  such  as  is  developed  farther  west.  In  some  cases  the 
sand  ndges  are  evidentl}^  wind-drifted,  and  probabh"  they  are  largely 
modified  by  wind.  They  occur  not  only  on  the  slope  between  Covert  till 
ridge  and  Lake  Michigan,  but  also  along  the  crest  of  that  ridge,  reacliing 
an  altitude  75  feet  or  more  above  Lake  Michigan.  In  a  few  places  gravel 
deposits  were  noted  on  the  imier  slope  of  tlie  till  ridge  at  an  altitude  as 
high  as  30  feet  above  the  lake.  They  are  well  displayed  along  the  main 
street  in  New  Buffalo  leading  southwest  from  the  post-office.  There  is  also 
a  good  exposure  southeast  of  the  Methodist  church,  the  depth  of  gravel 
being  several  feet.     In  the  vicinity  of  i]\v  i)ul)lic  school  building  there  are 


THE  GLACIAL  LAKE  CHICAGO.  433 

sand  deposits  several  feet  in  depth,  which  are  slightly  pebbly  near  the 
bottom. 

North  of  Galien  River,  about  2  miles  from  New  Buffalo,  in  sec.  36, 
T.  7  S.,  R.  21  W.,  a  Avell-deiined  gravel  ridge  sets  in,  which  leads  north  about 
a  mile  to  the  shore  of  Lake  Michigan.  It  is  6  or  8  feet  high,  20  to  30  rods 
in  width,  and  stands  by  surveyor's  level  55  to  58  feet  above  Lake  Michigan.^ 
This  appears  to  be  the  upper  beach  notwithstanding  that  sand  deposits  on 
neighboring  portions  of  Covert  Ridge  occur  at  90  to  100  feet  above  the 
lake.  The  presence  of  the  sand  at  these  higher  levels  seems  referable  to 
wind  transportation. 

For  a  mile  or  more  north  from  the  point  where  this  gravel  beach  comes 
to  the  lake,  Covert  Ridge  forms  the  immediate  bluff  and  rises  nearly  90  feet 
above  lake  level.  A  gravelly  beach  appears  on  its  northwest  slo^se  at  the 
lake  bluff,  in  sec.  19,  T.  7  S.,  R.  20  W.,  and  bears  north  of  east  to  Lakeside 
Station,  on  the  Chicago  and  West  Michigan  Railway.  The  gravel  has  an 
altitude  at  this  station  very  nearly  60  feet  above  Lake  Michigan,  but  in 
connection  with  it  there  are  sand  deposits  which  increase  the  altitude  of  the 
beach  to  nearly  70  feet  above  the  lake.  For  a  mile  or  inore  northeast  from 
Lakeside  the  beach  lies  a  short  distance  east  of  the  railway.  It  then  crosses 
to  the  west  side,  but  is  within  a  half  mile  of  the  railway  for  several  miles 
north.  At  Sawyer  Station  it  is  about  as  far  west  of  the  railway  as  at  any 
point,  while  at  Bridgman  it  is  along  the  railway  track.  It  usually  presents 
a  definite  gravelly  ridge  a  few  feet  high,  capped  in  places  by  sand  deposits 
several  feet  in  depth.  The  gravel  seems  to  hold  a  uniform  altitude  about 
60  feet  above  Lake  Michigan. 

A  sharp  sand  ridge  follows  the  crest  of  Covert  Ridge  for  a  few  miles  in 
the  vicinity  of  Bridgman  and  becomes  united  with  this  beach  about  mid- 
way between  Bridgman  and  Stevensville.  From  that  point  to  St.  Joseph 
the  sand  deposits  are  so  heavy  as  to  conceal  the  beach  line.  The  sand 
in  places  has  a  depth  of  20  or  30  feet  and  is  most  prominent  along  the 
crest  of  Covert  Ridge.  A  short  distance  southeast  of  Bridgman  it  passes 
down  the  outer  slope  of  Covert  Ridge  in  a  definite  belt  and  extends  to  the 
valley  of  Galien  River,  near  New  Troy.  The  continuity  of  this  belt  of 
sand  is  remarkable,  especially  since  it  lies  in  places  a  mile  or  more  east 

'  Elevations  determined  by  Mr.  Glavin,  formerly  county  surveyor. 
MOM   XXXVIII 28 


434  THE  ILLINOIS  GLACIAL  LOBE, 

of  the  upper  beach.  In  all  probability  it  was  deposited  by  wind,  for  it 
reaches  in  places  an  elevation  125  feet  above  the  lake,  or  about  60  feet 
above  the  upper  beach.     It  has  a  range  also  of  fully  60  feet  in  its  elevation. 

While  the  beach  was  forming  along  the  inner  face  of  Covert  Ridge  in 
southern  Berrien  County,  Michigan,  there  were  probably  bays  or  marshes 
occupying  the  low  land  back  of  the  ridge,  for  this  in  places  scarcely  rises 
to  the  level  of  the  beach.  An  examination  of  the  plains  drained  by  Galien 
River  brings  to  light  only  a  slight  sand  coating  and  little,  if  any,  evidence 
of  wave  cutting'.  The  greater  part  of  the  plain  stands  so  near  the  level  of 
the  upper  beach  that  there  were  probably  only  marshes  at  the  highest  lake 
stao-e.  The  sand  may  have  been  deposited  by  wind  or  perhaps  by  a  small 
lake  held  between  the  ice  border  and  the  Valparaiso  morainic  system.  In 
a  plain  between  the  outer  till  ridge  and  the  Valparaiso  system  near  the 
village  of  Baroda,  there  appears  to  be  slight  wave  cutting,  both  on  the 
border  next  to  the  Valparaiso  system  and  the  east  border  of  the  outer  till 
ridge  at  an  elevation  nearly  20  feet  above  the  level  of  the  upper  beach  as 
developed  on  the  inner  slope  of  Covert  Ridge.  There  are  also  conspicuoiis 
deposits  of  sand  to  a  height  of  10  feet  above  that  beach,  or  about  70  feet 
above  Lake  Michigan.  This  determination  led  the  writer  to  make  exam- 
inations along  the  base  of  the  Valparaiso  system  farther  north  and  also  of 
the  borders  of  the  till  ridges  toward  the  north  and  west  with  a  -sdew  to  fixing 
the  highest  limit  of  wave  action  and  ascertaining,  if  possible,  whether  the 
o-reater  height  of  wave  action  on  this  plain  is  due  to  a  small  lake  held  between 
the  ice  front  and  the  Valparaiso  system,  or  to  a  stage  of  Lake  Chicago  some- 
what higher  than  the  supposed  upper  beach  on  the  slope  of  Covert  Ridge. 

An  extensive  gravelly  plain,  apparently  a  delta,  is  found  back  of  Covert 
Ridge  on  the  border  of  the  St.  Joseph  River.  The  greater  part  of  this  delta 
stands  50  to  60  feet  above  Lake  Michigan,  or  sufficiently  low  to  be  connected 
with  the  60-foot  beach  of  Lake  Chicago.  In  the  midst  of  the  Valparaiso 
morainic  system  the  river  is  bordered  by  a  gravel  terrace  which  descends 
from  about  100  feet  above  the  lake  at  Niles  to  80  feet  at  Berrien  Springs, 
and  to  about  70  feet  at  the  point  where  it  exi)ands  into  the  delta.  On 
the  border  of  this  ten-ace  below  Berrien  Springs,  in  sees.  1  and  2,  T.  6  S , 
R.  18  "W.,  there  are  occasional  basins  8  or  10  feet  in  depth,  occupying  an  acre 
or  more  each,  whose  rims  stand  only  about  80  feet  above  Lake  Michigan. 
These  basins  apparently  stand  above  the  level  of  the  highest  stage  of  Lake 


THE  GLACIAL  LAKE  CHICAGO.  435 

Chicago ;  otherwise  they  would  have  been  obliterated  by  its  waves.  They 
seem  to  oppose  the  view  that  a  small  lake  held  between  the  ice  border  and 
the  Valparaiso  system  had  an  elevation  much  greater  than  that  of  the  sup- 
posed upper  beach  of  Lake  Chicago.  It  seems  not  improbable  that  such  a 
lake  may  have  stood  15  or  20  feet  above  that  beach,  but  it  scarcely  could 
have  exceeded  these  limits.  By  combining  the  evidence  from  the  St.  Joseph 
Valley  and  the  wave-washed  plain  near  Baroda,  one  is  inclined  to  consider 
the  wave  action  displayed  on  that  jDlain  the  product  of  a  small  lake  held 
between  the  ice  and  the  Valj^araiso  system  rather  than  a  stage  of  Lake 
Chicago  higher  than  that  which  formed  the  well-defined  beach  on  the  inner 
slope  of  Covert  Ridge. 

There  appears  to  have  been  a  bay  extending  up  the  Pawpaw  River 
Valley  at  the  highest  stage  of  Lake  Chicago  nearly  to  the  village  of  Hart- 
ford. It  appears  not  to  have  reached  the  site  of  that  village  since  the  low 
plain  bordering  the  river  is  found  to  carry  well-defined  basins  several  feet 
in  depth.  One  basin  in  the  east  part  of  the  village  occu.pies  5  or  6  acres 
and  has  a  depth  of  about  8  feet.  Near  Coloma  wave  action  along  the  base 
of  the  moraine,  south  of  Pawpaw  River,  seems  to  have  reached  an  altitude 
about  650  feet  above  tide,  or  70  feet  above  Lake  Michigan.  It  has  about 
the  same  altitude  immediately  south  of  Watervliet.  These  lines  of  wave 
action  are  only  about  15  feet  lower  than  the  plain  containing  basins  noted 
at  Hartford. 

There  are  a  few  exposures  of  gravel  in  St.  Joseph  at  about  60  feet 
above  Lake  Michigan,  but  frojn  St.  Joseph  northward  for  several  miles 
Covert  Ridge  forms  the  bluff  of  the  lake.  Near  the  line  of  Berrien  and 
Van  Buren  counties  it  bears  away  from  the  lake,  and  beach  deposits  are 
formed  on  its  inner  slope  a  mile  or  more  west  from  the  crest.  They  consist 
largely  of  sand,  there  being  only  occasional  small  pebbles.  It  is  not 
possible,  therefore,  to  determine  so  definitely  as  in  southern  Berrien  County 
the  upper  limits  of  the  lake.  The  evidence,  however,  seems  satisfactory 
that  the  lake  reached  an  elevation  nearly  70  feet  above  the  present  level  of 
Lake  Michigan. 

For  a  few  miles  north  of  South  Haven,  Covert  Ridge  again  forms  the 
bluff  of  the  lake  and  rises  above  the  level  of  the  upper  beach,  but  in  sec. 
25,  T.  1  N.,  R.  17  W.,  in  Allegan  County,  exposures  of  gravelly  sand  were 
found  on  its  slope  at  about  60  feet  above  lake  level.     Gravel  is  reported  to 


436  THE  illi:n'ois  glacial  lobe. 

have  been  found  near  Pier  Cove  at  the  base  of  sand  dunes,  at  a  slightly 
higher  level  than  60  feet,  but  this  place  was  not  visited  by  the  writer.  North 
from  the  mouth  of  the  Kalamazoo  River  only  a  brief  reconnaissance  was 
made,  so  that  the  full  extent  of  the  beaches  has  not  been  ascertained.  A 
very  strong  beach  appears  immediately  east  of  Holland,  on  the  south  side 
of  Black  River,  at  an  altitude  60  to  65  feet  above  Lake  Michigan.  This 
beach  appears  also  in  Zeeland.  Evidence  of  wave  or  current  action  at  a 
hiofher  altitude  is  found  a .  few  miles  east  and  south  of  Zeeland  on  the 
slopes  of  Covert  Ridge.  A  wave-washed  surface  is  found  at  an  altitude 
about  100  feet  above  Lake  Michigan,  in  the  vicinity  of  Vriesland,  and 
northward  from  there  to  the  border  of  Grand  River.  Passing  southwest- 
ward  from  Vriesland  a  sandy  belt  is  found  at  a  still  higher  level,  its  upper 
limits  being  about  120  feet  above  the  lake.  This  sandy  belt  is  well  dis- 
playe^l  at  Overisel  and  Filmore  Center  and  is  traceable  for  several  miles 
along  the  inner  slope  of  Covert  Ridge.  It  has  a  definite  ridging,  as  if 
marking  the  border  of  the  lake,  but  may  possibly  have  been  drifted  a  few 
feet  above  the  water  level.  In  that  case  the  water  level  here  may  have 
been  about  the  same  as  at  Vriesland,  or  very  nearly  100  feet  above  Lake 
Michigan.  Further  study  is  necessary  to  a  satisfactory  interpretation  of  the 
phenomena,  since  neither  of  the  two  beaches  mentioned  has  been  traced 
into  definite  connection  with  the  upper  beach  farther  south.  Possibly  the 
wave  action  displayed  on  the  slope  of  Covert  Ridge  east  and  south  of 
Zeeland  is  that  of  a  small  glacial  lake  contemporaneous  with  the  formation 
,  of  Zeeland  till  ridge.  The  general  weakness  of  the  beach  would  seem  to 
favor  this  interpretation.  An  alternative  hypothesis  would  refer  its  high 
altitude  to  northward  differential  uplift  and  make  it  constitute  the  continua- 
tion of  the  upper  beach  of  Lake  Chicago.  In  that  case  the  strong  beach 
standing  at  60  to  65  feet  would  be  the  continuation  of  the  Second  or 
Calumet  beach  of  Lake  Chicago.  This  matter  is  discussed  more  fully 
below. 

There  are  extensive  sand  plains  in  Allegan  County,  Michigan,  between 
the  Valparaiso  morainic  system  and  Covert  Ridge,  known  as  the  "Pine 
Plains,"  which  probably  throw  some  light  upon  the  altitude  of  the  highest 
stage  of  Lake  Chicago.  The  plains  are  traversed  nearly  centrally  b}"  the 
Kalamazoo  River  and  extend  nortli  to  Rapid  River.     Between  Kalamazoo 


THE  GLACIAL  LAKE  CHICAGO.  437 

and  Rapid  River  the  altitude  is  75  to  90  feet  above  Lake  Michigan.  Tlie 
portion  south  from  the  Kalamazoo  River  ranges  in  altitiide  from  70  feet  to 
fully  100  feet  above  the  lake,  being  highest  on  the  south  border.  The  sand 
ranges  in  depth  from  a  foot  or  two  up  to  fully  50  feet  and  appears  to  be 
thickest  on  the  borders  of  the  Kalamazoo  River.  If  we  except  the  southern 
border,  the  sand  deposition  seems  largely  referable  to  a  delta  accumulation 
made  by  Kalamazoo  and  Rapid  rivers,  beginning,  perhaps,  while  the  ice 
sheet  was  forming  Covert  Ridge  and  continuing  through  the  formation  of 
the  upper  beach  of  Lake  Chicago.  The  altitude  of  much  of  the  sand 
plain  is  such  as  to  correspond  somewhat  closely  with  that  of  the  upper 
beach  in  neighboring  portions  of  Van  Buren  County,  being  about  70  feet 
above  the  lake.  The  water  level  could  not  well  have  stood  hig-her  than  90 
feet  for  any  prolonged  period,  for  basins  were  observed  on  the  east  border 
of  the  sand  plain  near  Swan  Creek,  at  90  to  100  feet  above  Lake  Michigan. 
Probably  a  portion  of  the  sand,  especially  that  on  the  somewhat  elevated 
south  border,  was  deposited  in  connection  with  the  withdrawal  of  the  ice 
sheet  from  the  ValjDaraiso  morainic  system.  A  small  portion  also  may  have 
been  brought  in  as  a  wash  from  neighboring  portions  of  the  Valparaiso 
morainic  system,  which  here  consists  of  a  sandy  till  which  might  easily 
furnish  a  large  amount  of  sand  upon  erosion.  The  bulk  of  the  de^josit, 
however,  appears  to  be  referable  to  the  Kalamazoo  River  and  the  small 
neighboring  stream,  Rapid  River.  This  being  the  case,  the  lake  level  may 
be  confidently  placed  at  fully  70  feet  and  possibly  may  have  been  90  feet 
in  western  Allegan  County.  The  latter  elevation  would  fall  in  well  with 
the  elevation  of  the  wave-washed  surface  in  southern  Ottawa  County,  100 
feet  above  the  lake. 

Reviewing  the  preceding  statements  concerning  the  altitude  of  the 
upper  beach,  it  appears  that  there  is  little  variation  in  altitude  from  northern 
Cook  County,  Illinois,  around  the  head  of  Lake  Michigan,  to  St.  Joseph, 
Michigan,  the  elevation  being  usually  between  65  and  60  feet  above  the 
lake.  Upon  passing  northward  from  St.  Joseph,  the  e^^dence  from  river 
deltas  seems  to  support  the  view  that  there  has  been  a  slight  differential 
northward  uplift,  but  is  not  considered  conclusive.  The  western  shore  of 
the  lake  has  not  been  examined  sufficiently  to  afford  a  basis  for  comparison. 
One  observation  near  Waukegan  shows  what  appears  to  be  wave  action  at 


438  THE  ILLINOIS  GLACIAL  LOBE. 

a  higher  level  tlian  that  of  the  upper  beach  at  the  point  where  it  comes  to 
the  lake  in  noi-thern  Cook  County,  the  altitude  being  about  90  feet  above 
the  lake.  But  observations  by  the  winter  in  northern  Lake  County,  Illinois, 
and  by  Professor  Chambei'lin  in  southeastern  Wisconsiii  indicate  that  the 
upper  beach  continues  at  about  50  or  60  feet  above  Lake  Michigan. 

A  few  gravel  pits  have  been  ojDened  in  the  uj^per  beach  in  the  vicinity 
of  Chicago.  Probably  the  most  extensive  is  Haas's  pit,  near  Forest  Home 
Cemetery,  1  mile  south  of  Oak  Park.  This  is  opened  in  the  bar  described 
above  as  leading  southward  on  the  east  side  of  the  Des  Plaines  River. 
The  excavation  extends  from  the  east  side,  of  the  bar  west  past  the  center, 
and  shows  beds  dipping  at  various  angles,  but  all  toward  the  east.  The 
lower  bed,  which  is  mainly  sand,  decreases  in  thickness  in  passing  from  the 
higher  to  the  lower  part  of  the  bar.  The  overlying"  beds  are  thin  on  the 
higher  part  and  increase  in  thickness  toward  the  east  border  of  the  bar. 
The  coarser  deposits  appear  to  be  built  upon  the  sand  bar,  as  may  be  seen 
by  the  following  section.  Mr.  Haas  states  that  the  material  of  the  same 
bed  may  vary  greatly  in  coarseness  withiii  the  space  of  a  few  feet,  but  that 
throughout  the  entire  extent  of  the  pit,  whicli  covers  an  area  of  several 
acres,  the  dip  of  the  beds  is  uniformly  toward  the  east: 

Section  in  Haas's  gravel  pit,  near  Oak  Park,  Illinois. 

iDCbes. 

Brown  stainecl  gravel  capping  summit  and  slope 18-30 

Fine  gravel,  fresh  or  stained  but  little 24-48 

Sand,  very  thiu  at  top,  Ijut  increasing  toward  side  of  ridge 0-36 

Fine  gravel,  increasing  toward  side  of  ridge 0-48 

Fine  gravel,  which  passes  upward  from  near  the  east  side  of  the  excavation,  assuming  a  nearly 

horizontal  position  beneath  the  crest  of  the  ridge 40-48 

Sand,  thickening  toward  the  higher  part  of  the  ridge 6-36 

Another  gravel  pit  has  been  opened  in  the  beach  between  Salt  Creek 
and  Lagrange,  in  which  the  excavation  extends  from  the  east  side  of  the 
beach  westward  nearly  to  the  outer  slope.  It  has  a  depth  of  12  to  14  feet, 
and  exposes  a  series  of  beds  dipping  slightly  toward  the  east.  Tlie  upper 
5  feet  is  of  brown  stained  gravel;  the  lower  portion  is  a  fine  gravel  with 
very  little  stain.  In  the  gravel  there  are  sandy  pockets  and  also  thin  beds 
of  sand.  These  sandy  portions  in  some  cases  show  a  slight  effervescence 
with  acid,  but  are  not  nearly  so  calcareous  as  sand  found  at  similar  depth 
in  glacial  deposits. 


THE  GLACIAL  LAKE  CHICAGO.  439 

At  Dyer,  Indiana,  the  beach  is  crossed  bj  a  small  stream,  which 
exposes  the  following  section: 

Section  of  beach  in  bank  of  stream  at  Dyer,  Indiana. 

Feet. 

Sand 6 

Sandy  gravel 6 

Bluish  sandy  gravel,  with  water 3^ 

Yellowish- gray  clay ^ g 

Total 22 

At  Schererville  the  sand  has  a  depth  of  about  25  feet  on  the  crest  of 
the  ridge,  but  only  12  to  15  feet  at  the  inner  border,  and  thins  out  to  about 
8  feet  a  half  mile  north  of  the  crest. 

South  of  Michigan  City  the  gravel  in  the  beach  is  shown  by  wells  to 
have  a  depth  of  about  12  feet  and  rises  6  or  8  feet  above  the  bordering 
marsh  on  the  south.  This  appears  to  be  somewhat  more  than  the  usual 
depth  of  gravel  along  this  portion  of  the  lake  border. 

At  the  point  where  the  gravel  ridge  comes  to  the  lake  shore  north  of 
New  Buffalo,  Michigan,  the  gravel  is  10  or  12  feet  in  depth.  Sections  of 
two  wells  in  sec.  36,  located  on  this  ridge,  also  show  about  12  feet  of  gravel 
and  sand.  In  one  well  a  bluish  clay  is  interbedded  with  the  lower  portion 
of  the  gravel.  In  another  the  gravel  is  underlaid  by  2  or  3  feet  of  sand, 
and  this  deposit  rests  on  the  till. 

A  well  on  the  beach  west  of  Sawyer  penetrated  6  feet  of  sand,  beneath 
which  was  a  water-bearing  gravel,  which,  at  a  depth  of  6  feet,  furnishes 
sufficient  water  to  supply  several  families. 

In  the  sand  ridge  at  Overisel,  in  northern  Allegan  County,  wells  often 
pass  through  a  bed  of  brush  and  herbaceous  vegetation  at  the  bottom  of 
the  sand,  a  feature  which  indicates  that  the  sand  has  encroached  upon  a 
land  surface  at  that  point,  and  supports  the  view,  above  suggested,  that  it 
has  been  di-ifted  by  wind  slightly  above  tlie  general  level  of  the  old  water 
surface. 

Remains  of  animal  life  have  been  reported  only  at  a  few  points  along 
the  entire  length  of  the  portion  of  the  beach  examined,  and  none  have  been 
observed  by  the  writer.  Mr.  Haas  reports  that  shells  of  the  size  of  Unios, 
and  also  smaller  molluscan  shells,  have  been  found  in  a  bed  of  sand  at  the 
bottom  of  the  gravel  pit  which  he  has  opened  near  Oak  Park.  Upon  the 
request  that  he  preserve  any  shells  which  might  subsequently  be  found,  he 


440        ^  THE  ILLINOIS  GLACIAL  LOBE. 

responded  within  a  few  weeks  by  sending  a  shell  which  proved  to  be  the 
ordinary  oyster.  Since  the  beach  marks  the  border  of  a  lake  which  stood 
sufficiently  above  sea  level  to  maintain  a  strong  current  through  its  outlet, 
it  seems  highly  improbable  that  the  lake  was  occupied  by  marine  life  at 
this  time.  Upon  revisiting  the  gravel  pit  and  inquii'ing  particularly  into 
the  circumstances,  it  was  found  that  the  shell  was  jjicked  up  by  some  of  the 
workmen  near  the  base  of  the  pit.  But  it  was  also  found  that  there  are  a 
few  Indian  graves  which  extend  down  nearly  to  the  level  of  the  base  of 
the  pit.  The  shell,  therefore,  may  have  been  introduced  atthe  time  these 
gi-aves  were  made,  or  may  have  been  of  more  recent  introduction.  Remains 
of  terrestrial  life  have  also  been  found  in  this  gravel  pit.  Mr.  Haas  has 
preserved  fragments  of  the  tooth  of  a  mammoth  found  at  the  depth  of 
several  feet.  These  fragments  are  waterworn,  and  it  seems,  therefore,  quite 
probable  that"  they  were  embedded  during  the  formation  of  the  beach 

Another  locality  in  which  supposed  Unio  shells  have  been  reported  is 
found  in  a  marsh  on  the  inner  side  of  the  beach  north  of  New  Buffalo, 
Michigan.  Mr.  Gla^^n,  formerly  county  surveyor  of  Berrien  County, 
reports  having  observed  shells  as  large  as  the  ordinary  clam  shell  in  ditching 
near  the  borders  of  this  marsh.  He  has,  however,  preserved  none  of  the 
shells,  and  possibly  may  be  mistaken  in  his  identification.  So  far  as  known 
to  the  writer,  these  are  the  only  places  along  the  entire  length  of  the  upper 
beach  where  molluscan  shells  have  been  reported,  and  none  have  been  per- 
sonally found,  though  search  has  been  made  for  them  in  several  exposures 
and  excavations.  There  appears,  therefore,  to  have  been  a  great  scarcity  of 
molluscan  life  in  this  stage  of  Lake  Chicago. 

INTERVAL   OF   EMERGENCE. 

After  the  Glenwood  beach  "was  formed,  the  lake  appears  to  have  with- 
drawn from  the  plain  in  Illinois  lying  between  the  beach  and  the  shore  of 
Lake  Michigan.  To  what  extent  it  withdrew  within  the  present  limits  of 
the  lake  is  not  accui-ately  determined.  The  evidence  for  this  emergence 
near  Chicago  is  found  in  beds  of  peat}^  material  that  occur  beneath  gravel  of 
the  succeeding  lake  stage,  as  long  since  noted  by  Dr.  Andrews  and  dis- 
cussed in  his  paper  cited  above.  Similar  peaty  material  underlies  beach 
gravel  near  Michigan  City,  Indiana.  In  Wisconsin,  clay  beds  which  seem 
to  have  been  left  in  a  retiring  water  body,  and  which  are  covered  by  beach 


THE  GLACIAL  LAKE  CHICAGO.  441 

deposits  of  the  succeeding-  lake  stage,  are  referred  by  Chamberlin  to  the  same 
category.^ 

Along  the  east  shore  of  Lake  Michigan  evidence  of  emergence  is  foimd 
in  deep  channels  along  the  lower  courses  of  the  streams  tributary  to  the 
lake — channels  which  are  in  some  cases  excavated  in  the  till  and  therefore  of 
later  date  than  the  last  ice  invasion.  Attention  was  called  to  these  chan- 
nels many  years  ago  by  Dr.  Alexander  Winchell."  They  were  subse- 
quently discussed  by  Dr.  C.  W.  Wooldridge.''  '  The  latter  made  a  special 
study  of  the  lower  course  of  White  River,  known  as  White  Lake,  and  also 
made  a  reconnaissance  from  Grand  Traverse  Bay  to  the  mouth  of  Grand 
River.  He  made  the  important  discovery  that  the  beds  of  several  of  these 
streams  ' '  are  excavated  in  the  drift  clay  and  not  in  the  surface  sand  which 
overspreads  the  lower  levels  in  their  Aacinity."  On  the  borders  of  White 
Lake  the  sand  is  usually  only  a  thin  deposit  1  to  4  feet  in  depth  and  the 
clay  surface  reaches  a  height  of  15  to  30  feet  above  the  level  of  the  lake. 
Similar  features  are  found  on  Duck  Lake,  Pentwater  Lake,  and  Manistee 
Lake.  The  latter  observation  carries  the  emergence  well  into  the  northern 
half  of  the  Lake  Michigan  Basin. 

The  depth  to  which  the  erosion  extended  is  difficult  to  determine,  since 
these  channels  have  no  doubt  been  filled  to  some  extent  during  the  subse- 
quent emergence.  Dr.  Wooldridge  found  a  point  near  the  mouth  of  White 
Lake  in  which  there  is  84  feet  (14  fathoms)  of  water.  The  U.  S.  Lake 
Survey  charts  show  a  depth  of  several  fathoms  in  each  of  the  tributaries  of 
Lake  Michigan  from  Pere  Marquette  Lake  southward  to  the  Kalamazoo 
River,  as  follows: 

Depths  of  lakes  tributary  to  LaTce  Michigan. 

Fathoma. 

Pere  Marqiiette  Lake 7 

Pentwater  Lake g 

White  Lake 10 

Muskegon  Lake g 

Spring  Lake 7 

Black  Lake 5 

Kalamazoo  River  * Ig  j 

The  above  soundings  demand  an  emergence  of  at  least  50  feet  above 
the  present  shore,  even  if  the  bottoms  are  but  slightlj^  filled,  and  it  seems 

1  Wisconsin  Geological  Survey,  Vol.  II,  pp.  221-224,  229,  230. 

2 Harper's  Magazine,  July,  1871,  p.  284. 

=  Amer.  Geologist,  A^ol.  I,  March,  1888,  pp.  143-146. 

■•Possibly  the  sounding's  at  mouth  of  Kalamazoo  River  represent  feet  instead  of  fathoms. 


442  THE  ILLIJfOIS  GLACIAL  LOBE. 

not  improbable  tliat  the  amoiint   of  filling  is  such  as  to  necessitate  the 
assumption  of  an  even  greater  emergence  in  that  region. 

The  simplest  conception  of  the  lake  history  would  postulate  onlv  one 
period  of  emergence,  but  the  available  data  suggest  greater  complication. 
It  remains  to  be  determined  whether  the  deep  channeling  may  not  peitaiu 
to  a  later  interval  of  emerg-ence  in  which  there  was  greater  uplift  than  in 
the  interval  under  consideration.  Observations  made  by  the  writer  in  the 
vicinity  of  Holland,  Michigan,  lead  to  the  -sdew  that  the  channeling  occun-ed 
subsequent  to  the  formation  of  the  strong  beach  which  stands  60  to  65  feet 
above  Lake  Michigan,  and  prior  to  the  formation  of  a  beach  which  stands 
about  25  feet  above  the  lake.  If  the  60-foot  beach  proves  to  be  a  contin- 
uation of  the  Calumet  or  Second  beach  of  Lake  Chicago,  this  emergence 
would  seem  to  have  occurred  between  the  formation  of  the  Second  and  Third 
beaches;  but  if  it  represents  the  Glenwood  beach,  the  emergence  may  have 
been  in  the  interval  under  discussion.  This  would  throw  it  into  the  same 
category  with  the  peaty  deposits  noted  near  the  south  end  of  the  lake. 
The  lake  charts  indicate  that  the  lower  courses  of  tributaries  on  the  west 
side  of  Lake  Michigan  are  not  characterized  by  the  deep  channels  which 
are  common  on  the  east  side  of  the  lake.  This  may  .be  attributable  in  part 
to  their  being  in  a  more  elevated  part  of  the  lake  border,  in  which  chan- 
neling was  so  narrow  that  it  has  been  completely  filled.  The  absence  of 
deep  channels  at  the  south  end  of  the  lake  may  be  due  to  obliteration  by 
sand  accumulations.  It  seems  very  doubtful  if  one  shore  suftered  much 
gi'eater  uplift  than  the  other.  Further  light  is  necessary  to  a  satisfactory 
interpretation  of  the  evidence  of  a  low  lake  level.  The  relation  of  the 
Third  beach  to  these  deep  river  channels  on  the  east  side  of  Lake  Michigan 
is  set  forth  on  a  later  page,  as  are  also  evidences  favoring  the  view  that 
channeling  occun-ed  subsequent  to  the  formation  of  the  Second  beach. 

THE   SECOND    OR   CALUMET   BEACH. 

This  beach  throughout  much  of  its  course  in  Indiana  follows  the  south 
border  of  Calumet  River,  and  because  of  this  close  association  the  name 
Calumet  seems  approjiriate.  From  Chicago  around  to  St.  Joseph,  Michigan, 
it  stands  aljout  20  feet  lower  than  the  u])per  beach,  but  it  may  be  separated 
somewhat  more  widely  from  that  beach  farther  north.  An  interval  of  about 
35  feet  is  found   l)ct\veen  the  upper  limits  of  wave  action  east  of  Holland, 


THE  GLACIAL  LAKE  CHICAGO.  443 

Michigan,  and  the  strong  beach  which  occui-s  at  60  to  65  feet  above  the 
lake.     Tracing  somewhat  in  detail,  its  course  is  as  follows: 

From  the  Wisconsin  line  southward  to  Chicago  River,  just  above  the 
city  of  Chicago,  it  is  closely  associated  with  the  upper  beach,  so  that  where 
one  beach  is  cut  away  by  the  lake  the  other  is  also.  The  Second  beach 
flanks  the  inner  border  of  the  upper  beach  in  Niles  Township.  From  the 
Chicago  River  to  the  Des  Plaines  the  Second  beach  is  separated  from  the 
upper  beach  by  an  interval  of  li  to  3  miles  and  passes  somewhat  directly 
from  Jefferson  Park  through  Austin  to  Riverside.  The  head  of  the  outlet 
of  Lake  Chicago  at  this  stage  was  at  a  line  connecting  the  villages  of  River- 
side and  Summit.  The  beach  gravels  are  well  developed  for  a  short  distance 
below  Summit  on  the  east  side  of  the  outlet,  while  the  west  side  is  marked 
by  a  cut  bank  of  corresponding  elevation.  The  beach  proper  leads  some- 
what directly  southeastward  froiii  Summit  to  the  north  end  of  Blue  Island 
Ridge  and  then  southward  along  the  east  side  of  the  ridge,  past  Washington 
Heights,  coming  to  the  Calumet  River  2  or  3  miles  east  of  Blue  Island. 
The  Sag  outlet  had  its  head  at  this  time  in  a  wide  opening  between  the 
Calumet  River  and  Thornton.  Immediately  east  of  Thornton  the  beach 
appears  in  its  customary  strength  and  passes  thence  eastward  into  Indiana. 

Upon  entering  Indiana  the  beach  follows  the  south  border  of  Calumet 
River  across  Lake  County  and  western  Porter  County  to  the  ^^oint  where 
the  upper  beach,  as  noted  above,  passes  to  the  north  side  of  the  river.  It 
is  closely  associated  with  the  upper  beach  from  near  the  village  of  Ross, 
Indiana,  eastward.  It  is  also  closely  associated  with  it  for  several  miles 
east  from  the  point  where  it  crosses  the  Calumet  River,  but  in  the  vicinity 
of  Furness  the  two  beaches  become  separated  by  a  nearly  level  swampy 
tract,  about  one-half  mile  in  width,  and  continue  distinct  to  Trail  Creek, 
just  east  of  Michigan  City.  The  Second  beach  passes  tlirough  the  south 
part  of  that  city. 

Upon  passing  into  Michigan,  this  beach  becomes  so  greatly  obscured 
by  the  belt  of  dunes  formed  along  the  border  of  the  lake  that  exposures  are 
found  only  at  a  few  points.  In  several  places  in  Bei-rien  and  Van  Buren 
counties  it  was  recognized  and  found  to  have  an  altitude  35  or  40  feet 
above  Lake  Michigan.  The  exposures  in  every  case  are  along  the  bluif  of 
the  lake.  As  already  indicated,  the  Avriter  has  had  opportunity  to  make 
onl)^  a  hurried  reconnaissance  of  tbe  lake  border  northward  from  Van  Buren 


444  TidlE  ILLINOIS  GLACIAL  LOBE. 

County,  and  can  not  therefore  speak  with  certainty  concerning  the  continu- 
ation of  the  beach.  The  beach,  which  on  the  whole  seems  to  be  the  most 
natural  continuation,  stands  60  to  65  feet  above  the  lake  on  a  line  examined 
eastward  from  Holland.  Its  relation  to  the  other  beaches  is  similar  to  that 
found  farther  S(iuth,  there  being-  one  beach  between  it  and  the  present 
beach  of  Lake  j\Iichigan,  and  aiiother  beach  or  similar  evidence  of  wave 
action  at  a  level  above  that  of  this  beach.  The  character  of  the  wave  action 
and  shore  markings  of  the  upper  level  have  alread}-  been  noted. 

An  important  bar  was  formed  at  this  stage  of  the  lake  just  north  of 
Chicago.  Its  northern  end  aj^pears  at  the  bluff  of  the  lake  between  Wil- 
mette  and  Evanston,  and  leads  thence  southward  through  the  west  part  of 
Evanston  to  Rose  Hill  Cemetery,  where  it  turns  abruptly  westward  and 
terminates  in  Bowmanville,  on  the  east  bluff  of  Chicago  River.  It  is 
probable  that  this  bar  was  attached  to  the  old  shore  at  some  point  farther 
north  than  its  present  terminus,  a  portion  of  it  ha^dng  been  removed  bv  the 
encroachments  of  Lake  Michigan.  The  l)ay  back  of  this  bar  had  a  width 
of  1  to  4  miles  and  a  depth  of  15  to  20  feet  in  its  deepest  jjart.  A  larg-e 
portion  of  it  was  so  shallow  as  probably  to  be  marshy.  Notwithstanding 
the  presence  of  this  bar,  the  beach  back  of 'it  ajjpears  to  have  been  acted 
upon  by  lake  waves  with  nearly  as  much  vig-or  as  the  portion  of  the  beach 
farther  south,  a  feature  which  suggests  the  absence  of  the  bar  in  the  earl}- 
stages  of  this  lake  le-s-el.  The  bar  is  much  more  bulky  than  an^-  part  of 
the  beach  proper,  being  10  to  20  feet  in  height  and  nearly  one-fourth  mile 
in  average  l:)readtli,  if  the  sand  and  gravel  on  its  Ijoiders  are  included. 

The  Second  beach  is  on  the  whole  characterized  by  larger  deposits  of 
gravel  and  sand  than  the  upper,  but  it  has  less  conspicuous  cut  banks.  Its 
.strength  is  greater  in  the  vicinit}'  of  the  northern  outlet  and  on  the  north 
side  of  the  southern  outlet  than  at  points  either  between  or  outside  the  out- 
lets. In  Indiana  and  Michigan,  however,  it  is  quite  large,  but  is  heavily 
covered  with  sand,  M'liich  is  largely  wind-drifted.  In  places  these  accunui- 
lations  of  sand  reach  a  lieight  of  30  or  40  feet. 

In  respect  to  the  remains  of  life,  this  beach  is  similar  to  the  upper 
beach.  Very  few  reports  of  the  occurrence  of  shells  were  received,  and 
no  shells  were  found  in  the  beach  by  the  writer.  It  is  in  striking  contrast 
with  the  next  lower  beach,  which  is  in  places  highly  fossiliferous. 


THE  GLACIAL  LAKE  CHICAGO.  445 

An  excellent  exposui-e  of  the  structure  of  the  bar  noted  above  is  found 
immediately  north  of  Evanston,  where  the  lake  is  undermining  the  bar  as 
well  as  subjacent  deposits.  The  gravel  and  sand  forming  the  bar  rest  iipon 
a  bed  of  peat,  which  was, long  since  noted  by  Dr.  Edmund  Audi'ews  and 
interpreted  by  him  to  be  the  accumulation  of  a  marsh  or  partially  sub- 
merged laud  surface.^  The  peat  not  only  underlies  this  bar,  but  extends 
eastward  across  the  interval  between  it  and  the  Third  beach.  Its  level  is 
no  higher  than  that  of  the  Third  beach,  being  only  12  to  15  feet  above  the 
present  level  of  Lake  Michigan.  The  peat  is  in  places  several  feet  thick, 
but  at  the  point  where  the  bar  comes  out  to  the  lake  shore  it  has  a  thick- 
ness of  only  a  few  inches.  It  there  contains  piece's  of  wood  which  show 
evidence  of  disturbance  by  waves.  Between  the  peat  and  the  yellowish 
blue  till  that  forms  the  base  of  the  exposure  there  is  a  gravelly  sand  6  to 
18  inches  in  thickness  which  appears  to  be  a  lacustrine  deposit.  The  peat 
is  immediately  overlaid  by  about  5  feet  of  sand,  above  which  there  is  a  bed 
of  coarse  gravel.  The  gravel  is  thin  near  the  borders  of  the  bar,  but  has  a 
thickness  of  1 0  or  12  feet  at  the  highest  pai't.  It  is  capped  by  a  thin  deposit 
of  sand,  and  has  also  layers  of  sand  interbedded  in  its  thickest  part.  The 
presence  of  this  gravel  makes  it  certain  that  the  old  marshy  land  sui'face 
has  not  been  buried  by  the  drifting  of  material  from  the  lower  beach. 
There  seems  no  escape  from  the  conclusion  that  the  lake  stood  at  a  lower 
stage  than  the  level  of  the  Second  beach  before  that  beach  and  the  bar 
under  discussion  were  formed. 

For  a  few  miles  in  the  vicinity  of  the  State  line  of  Indiana  and  Michigan 
there  are  exposures  of  peaty  material  along  the  bluff  of  Lake  Michigan  at 
levels  ranging  from  about  15  feet  above  the  lake  down  to  the  water's  edge. 
The  peaty  layers  are  seldom  more  than  6  inches  thick  and  are  interbedded 
with  sand.  One  layer  standing  12  to  15  feet  above  the  lake  appears  1^  to 
2  miles  southwest  of  New  Buffalo  and  is  traceable  continuously  for  fully 
one-half  mile.  Near  Michigan  City  peaty  layers  just  above  the  water's  edge 
are  nearly  continuous  for  a  distance  of  a  mile  or  more,  and  occur  at  frequent 
intervals  from  Michigan  City  to  the  Michigan  State  line.  Above  the  peaty 
beds  pebbly  sand  in  places  reaches  an  elevation  of  30  feet  above  the  lake, 
or  nearly  to  the  level  of  the  Second  beach.     The  peat  appears,  therefore,  to 

'  Trans.  Chicago  Acad.  Sci.,  Vol.  II,  1870. 


446  THE  lLI,moIS  GLACIAL  LOBE. 

have  been  developed  prior  to  the  formation  of  that  beach,  and  probably 
has  the  same  age  as  that  noted  near  Evanston,  Illinois. 

POSSIBLE   SECOND   EMERGENCE. 

As  indicated  above,  features  near  Holland,  Michigan,  apparently  call 
for  an  interval  of  emergence  there  between  the  formation  of  beaches  which 
stand  second  and  third  in  the  series  of  that  region.  Immediately  south  and 
east  of  Holland  a  beach  is  built  up  from  the  level  of  the  plain  on  which 
Holland  stands,  which  is  30  to  40  feet  above  Lake  Michigan,  to  an  elevation 
60  to  65  feet  above  the  lake.  It  consists  of  sandy  gravel,  becoming  in 
places  nearly  clear  sand.  In  connection  with  this  deposit  there  is  a  sandy 
gravel  which  extends  2  miles  or  more  up  the  Black  River  Valley,  and  has 
the  appearance  of  being  a  delta  accumulation  formed  by  a  larger  stream 
than  the  present  river.  A  broad  abandoned  channel  nearly  a  mile  in  width 
leads  from  Grand  River  just  below  Grand  Rapids  southwestward  to  the 
Black  River  Valley  at  Holland,  which  has  opened  a  broad  passage  through 
this  delta,  or  rather  a  double  channel,  with  an  island-like  remnant  of  the 
old  delta  south  of  Zealand.  The  amount  of  erosion  would  be  great  if  it 
had  extended  only  to  the  level  of  the  marsh;  but  judging  from  the  depth  of 
the  channel  of  Black  River  from  Holland  westward  to  Lake  ]\Iichigan, 
which,  as  shown  above,  reaches  a  level  30  feet  below  the  lake,  the  marsh 
has  been  greatly  filled  during  the  formation  of  a  lower  beach  which  crosses 
Black  River  at  Holland.  The  filling  can  not  well  be  less  than  50  feet. 
This  depth  of  excavation  not  only  increases  the  work  done  but  indicates 
that  there  was  sufficient  emergence  above  the  level  of  the  present  shore  of 
Lake  Michigan  to  cause  stream  channeling  to  extend  30  feet  or  more  below 
lake  level.  The  relation  of  the  lower  beach  to  the  head  of  the  lake-like 
expansion  of  Black  River  is  discussed  in  connection  with  the  Third  or 
Tolleston  beach. 

Deep  channeling  on  the  lower  course  of  other  eastern  tributaries  of 
Lake  Michigan,  above  noted,  appears  to  have  occurred  contemporaneously 
with  that  of  Black  River.  What  relation  this  channeling  may  liave  to  the 
Algonquin  and  Nipissing  lake  stages  is  yet  to  be  determined.  During  each 
of  these  lake  stages  the  water  in  the  south  part  of  the  Lake  Michigan  Basin 
is  thought  by  those  who  have  studied  their  beaches  to  have  been  below  the 
present  level  of  Lake  Michigan.     But  it  is  also  thought  that  in  the  northern 


THE  GLACIAL  LAKE  CHICAGO.  447 

part  of  the  basin  these  lakes  extended  beyond  the  present  shore.  As  the 
deep  channehng  of  the  valleys  is  continued  well  into  the  north  half  of 
the  basin,  it  may  prove  to  be  independent  of  the  supposed  Algonquin  and 
Nipissing  lake  levels  in  that  region. 

THE   THIRD    OR   TOLLESTON   BEACH 

This  beach  received  its  name  from  the  village  of  ToUeston,  situated  in 
northwestern  Indiana  at  the  crossing  of  the  Pittsburg,  Fort  Wayne  and 
Chicago  and  the  Michigan  Central  railways,  at  a  point  immediately  south 
of  the  extreme  head  of  Lake  Michigan,  and  distant  only  2^  miles  from  the 
head  of  the  lake.  It  is  more  complex  than  either  of  the  higher  beaches. 
Indeed,  it  is  a  matter  of  no  small  difficulty  to  determine  what  beachlets 
should  be  included  with  this  lake  stage.  There  are,  b}^  actual  count,  32 
beachlets  crossed  on  a  north-south  line  about  3  miles  east  of  the  State  line 
of  lUinois  and  Indiana.  The  outer  line  of  this  series  is  usually  much 
stronger  than  the  others  and  stands  a  few  feet  higher,  and  hence  is  consid- 
ered the  main  line.  The  village  of  Tolleston  and  also  Hessville  and  Miller 
Station,  in  Indiana,  are  situated  on  the  outermost  or  main  line. 

Many  of  the  beachlets  situated  between  the  main  line  and  the  shore  of 
Lake  Michigan  stand  only  10  to  12  feet  above  that  lake,  and,  as  shown 
farther  on,  seem  to  have  been  formed  after  the  southwestward  outlet  was 
abandoned.  This  being  the  case,  they  may  not  be  referable  to  Lake  Chi- 
cago. The  Third  or  Tolleston  beach,  as  here  described,  includes  only  such 
beaches  and  bars  as  have  sufficient  elevation  above  the  sill  of  the  Chicago 
Outlet  to  indicate  that  they  are  connected  with  that  outlet — beaches  whose 
elevation  is  18  to  25  feet  above  the  level  of  Lake  Michig-an. 

The  portion  of  the  shore  of  this  lake  stage  in  Lake  County,  Illinois, 
is  closely  associated  with  that  of  the  higher  lake  stages  and  consists  of  a 
gravelly  deposit  flanking  the  foot  of  the  old  lake  bluff.  In  Cook  County 
this  beach  appears  at  the  lake  bluff  on  the  grounds  of  the  Northwestern 
University,  in  Evanston,  and  for  several  miles  south  it  lies  near  the  east 
border  of  the  bar  formed  at  the  next  preceding  lake  stage.  From  Rose 
Hill  Cemetery  southward  it  is  beyond  the  limits  of  the  bar,  but  is  perhaps 
itself  a  bar  built  out  southward  into  a  bay  now  traversed  by  Chicago 
River.  It  appears  to  have  reached  some  distance  south  at  an  early  part  of 
this  lake  stage,  for  only  a  poorly  defined  beach  appears  on  the  west  side  of 


448  THE  ILLINOIS  GLACIAL  LOBE. 

the  bay  back  of  it.  j\Ir.  W.  C.  Alden  has  found  shght  traces  of  the  beach 
in  the  west  part  of  Chicago.^  This  bar  Hes  within  a  mile  of  the  present 
shore  of  Lake  Michigan  and  is  readily  traced  as  far  south  as  Lincoln  Park. 
The  bar  is  said  to  have  been  nearly  continuous  tlu'ough  the  city  of  Chi- 
cagd,  but  in  grading  up  the  business  portion  of  the  city  it  has  been  oblit- 
erated from  Lincoln  Park  southward  nearly  to  the  Douglas  Monument,  and 
the  writer  has  been  unable  to  obtain  a  map  or  other  accurate  data  showing 
its  former  extent.  The  bar  is  preserved  from  the  Douglas  Monument 
southward  to  Englewood,  a  distance  of  4  or  5  miles.  This  portion  consists 
of  a  series  of  overlapping  ridges,  of  which  the  westernmost  or  earlier  ter- 
minate farther  north  than  their  successors  on  the  east.  At  the  termination 
of  each  of  these  ridges  a  hook  turns  out  to  the  west  into  the  bay  that  stood 
west  of  the  bar.  An  outlet  seems  to  have  been  maintained  toward  the  Des 
Plaines  around  the  southern  end  of  this  advancing  bar,  until  it  reached 
Englewood.  This  may  not  have  been  closed  until  the  water  level  had 
dropped  too  low  for  a  discharge  to  the  Des  Plaines.  It  formed  a  well- 
defined  gravelly  shore  in  its  north  border  from  the  Hawthorn  quarry  west- 
ward to  Riverside,  as  determined  by  Mr.  Alden.  Upon  passing  across  the 
outlet  marsh  from  Englewood  to  South  Lynne  one  finds  a  continuation  of  the 
Tolleston  beach,  which  leads  northwestwai'd  to  the  Des  Plaines  at  Summit. 
From  South  Lynne  it  leads  in  a  course  east  of  south  to  South  Englewood 
and  thence  more  nearly  east  across  the  northwest  corner  of  Calumet  Town- 
ship into  Hj^de  Park,  coming  to  the  Illinois  Central  Railway  a  short  distance 
north  of  Pullman.  From  this  point  a  gravelly  ridge  is  traceable  southward 
past  the  north  border  of  Lake  Calumet,  where  it  dies  out  in  the  marsh.  A 
slight  beach  is  formed  to  the  northeast  from  here  on  Stony  Island,  between 
Lake  Calumet  and  South  Chicago.  But  the  main  line  of  this  beach  is 
found  west  of  Lake  Calumet,  running  north  and  south  through  the  west 
parts  of  Pullman  and  Kensington,  where  it  usually  has  the  form  of  a  cut 
bank  10  to  15  feet  in  height,  but  changes  to  a  gravelly  and  sandy  beach  at 
the  south.  This  beach  comes  to  the  Calumet  River  at  Riverdale,  where  it 
connects  with  the  Sag  outlet.  It  reappears  on  the  south  side  of  the  river 
,at  Dolton  and  passes  thence  southeastward  into  Indiana. 


'  Mr.  Alden  bas  made  a  thorough  mapping  of  the  surface  deposits  of  the  Chicago  and  Calumet 
quadrangles  for  this  Survey. 


THE  GLACIAL  LAKE  CHICAGO.  449 

Its  course  iu  Lake  County,  Indiana,  is  eastward  through  Hessvilie 
and  ToUeston  and  Miller.  Farther  east  it  becomes  lost  beneath  the  dunes 
that  border  Lake  Michigan.  From  the  vicinit}^  of  Michigan  City,  Indiana, 
northward  through  Berrien,  Van  Buren,  and  Allegan  counties,  Michigan,  it 
has  been  extensively  removed  by  Lake  Michigan,  for  the  lake  bluff  usually 
rises  above  its  level  and  j)i'eseuts  deposits  as  old  as  the  Second  beach. 

The  first  appearance  of  a  low  beach  of  any  notable  extent  in  Michigan 
is  that  found  in  the  ^dcinity  of  the  line  of  Allegan  and  Ottawa  counties, 
south  of  the  lake-like  expansion  of  Black  River.  This  beach  leads  from 
the  shore  of  Lake  Michigan  eastward  to  Holland,  Michigan,  and  there 
takes  a  northward  course,  crossing  Black  River  at  the  head  of  its  lake-like 
expansion.  It  stands  about  25  feet  above  Lake  Michigan,  except  where 
sand  dunes  have  given  it  greater  height.  Along  Black  River  Valley  above 
this  beach  there  is  a  gravel  filling,  apparently  a  later  delta  than  that 
described  above,  built  up  to  about  25  feet  above  Lake  Michigan,  at  the 
point  where  the  beach  crosses,  but  rising  to  fully  30  feet  near  Zeeland,  3 
miles  east.  At  the  head  of  this  delta  there  is  a  marshy  valley  with  a  width 
of  a  half  mile  or  more,  which  connects  at  the  northeast  with  the  valley  of 
Grand  River,  as  indicated  above.  The  bottom  of  this  marshy  valley  at 
the  present  divide,  near  Hudsonville,  as  shown  by  the  Chicago  and  West 
Michigan  Railway  survey,  stands  about  45  feet  above  Lake  Michigan,  thus 
allowing  only  15  feet  fall  from  Hudsonville  to  Zeeland,  a  distance  of  fully 
12  miles.  Below  the  point  where  this  beach  crosses  Black  River  there  is, 
as  above  stated,  a  channel  which  extends  30  feet  or  more  below  Lake 
Michigan.  It  is  a  half  mile  to  1  mile  in  width,  being  as  broad  as  the 
gravel-filled  valley  above.  From  the  gravel  filling  to  the  bottom  of  this 
channel  there  is  a  descent  of  50  or  60  feet  in  less  than  2  miles.  It  is 
probable,  therefore,  that,  at  the  point  where  the  beach  crosses,  the  filling 
reaches  at  least  50  feet.  The  cause  for  the  abrupt  termination  of  the  deep 
part  of  the  lower  course  of  Black  River  appears,  therefore,  to  be  due  to 
the  covering  of  this  part  by  lake  water  while  the  beach  and  delta  were 
forming  at  the  edge  of  the  lake.  It  seems  probable  that  the  abi'upt  termi- 
nation of  the  deep  part  of  tributaries  of  Lake  Michigan  north  from  this 
one  is  due  to  a  similar  relation  to  a  beach,  but  this  is  merely  an  inference, 
as  that  region  has  not  been  visited  by  the  writer.     Much  remains  to  be 

MON  XXXVIII 29 


450  THE  ILLINOIS  GLACIAL  LOBE. 

determined  concerning  the  development  of  channels  in  this  region  and  their 
modification  during  the  high  lake  stag'e  or  stages. 

The  portion  of  tliis  beach  in  Illinois  consists  mainh^  of  fine  gravel,  which 
is  nsnally'well  worn,  but  in  places  has  considerable  angular  material,  as  if 
formed  rapidly  and  subjected  for  but  a  brief  period  to  the  action  of  the  lake 
waves.  The  low  district  along  the  Chicago  River  back  of  this  beacli  has 
received  quite  generally  a  coating  of  sand  several  feet  in  depth,  and  the 
marshy  tracts  in  Hyde  Park  and  Lake  townships  are  also  covered  with 
sand  to  a  depth  of  several  feet.  Excavations  have  shown,  however,  that 
till  usually  sets  in  at  a  depth  of  10  to  20  feet  or  less.     (Alden.) 

In  Indiana  this  beach,  like  the  present  shore  of  Lake  Michigan,  is  very 
sandy.  Its  dunes,  however,  seldom  reach  a  greater  height  than  50  feet,  or 
but  one-third  to  one-quarter  the  height  of  dunes  on  the  present  shore. 
Wells  along  it  have  occasionally  encountered  a  bed  of  gravel  at  the  base  of 
the  sand  at  levels  corresponding  with  the  gravelly  beaches  of  the  Illinois 
portion. 

One  of  the  best  exposures  of  this  beach  is  found  at  the  border  of  the 
campus  of  the  Northwestern  University,  at  Evaustou,  Illinois.  The  follow- 
ing sections,  one  taken  by  Dr.  Oliver  Marcy,  in  1864,  at  which  time  there 
was  a  peculiarly  good  exposure,  the  other  taken  by  the  Avriter  in  1887,  at 
which  time  there  was  a  less  extensive  exposure,  show  a  slightly  different 
section.  The  beach  in  this  interval  had  suffered  au  erosion  of  perhaps  75 
or  100  feet. 

Section  of  beach  at  Evanston  made  in  1864. 

Feet. 

Surface  soil,  sandy li 

Brown  sand  and  fine  gravel -h 

Coarser  gravel,  stratified 2i 

Fine  sand 2 

Gravel,  containing  bones  of  deer ..^ li 

Fine  sand,  containing  oak  logs 1* 

Peat  or  carbonaceous  earth  with  a  marl  bed  containing  molluscan  shells  in  the  lower  portion,  or 

interstratilied  with  the  peat H 

Gravel 3i 

Humus  soil,  with  stumps  and  logs  (coniferous) } 

Yellow  clay,  laminated  and  contorted,  containing  pockets  of  gravel 3* 

Blue,  pebbly  clay 2 

Height  of  bluff -'2 


THE  GLACIAL  LAKE  CHICAGO.  451 

Section  of  beach  at  Uvanston  made  in  1887. 

Feet.  In. 

Yellowish-red,  iron-stained  sand 3-5 

Band  of  bog  iron  ore 4-6 

Gravel  with  beds  of  sand  included  (the  stratification  is  very  irregular  in  thickuess  and 

assorting  very  imperfect) 5  -  7 

Coarse  sand,  not  calcareous 6-12 

Calcareous  loam 3 

Yellow  clay,  very  calcareous,  with  leaves  embedded 3 

Carbonaceous  band,  not  calcareous .' 2 

Yellow  carbonaceous  clay,  calcareous 4-  6 

Band  of  carbonaceous  material,  not  calcareous 2 

Brown  sand,  with  twigs  and  peaty  material 8-10 

Water-bearing  sand  and  talus-covered  slop  8 

Height  of  bluff 22    0 

The  calcareous  clays  of  each  section  contain  numerous  gasteropod 
shells.  Dr.  Marcy  has  collected  a  large  number  of  shells  from  them,  among 
which  there  are  Unios,  apparently  of  several  different  species  but  not  specif- 
ically identified.  Mr.  C.  T.  Simpson  has  identified  nine  different  genera  of 
moUusks,  all  of  existing  species,  found  in  the  peat  and  marl  bed  of  Dr. 
Marcy's  section.  Planorbis  and  Lymneea  are  very  abundant.  Prof  D.  P. 
Penhallow  has  identified  two  wood  specimens,  one  a  new  species  of  Picea 
(Picea  evanstoni),  the  other  a  new  oak  (^Quercus  marcy  ana)}  The  bone 
of  the  deer  found  by  Dr.  Marcy  is  a  portion  of  the  femur.  The  writer  has 
found  many  localities  in  the  sandy  portions  of  this  beach,  where  moUuscan 
shells  abound.  Nearly  every  exposure  in  the  sandy  district  west  of  the 
beach,  from  the  main  part  of  the  city  of  Chicago  southward  to  Englewood, 
exhibits  them.  This  beach  is,  therefore,  in  striking  contrast  with  the  two 
higher  beaches,  which  contain  few  shells  or  other  remnants  of  life. 

An  excellent  artificial  section  across  this  beach,  made  by  the  Fullerton 
avenue  conduit,  which  leads  from  the  Chicago  River  eastward  to  Lake 
Michigan,  across  the  north  part  of  Chicago,  is  discussed  above.  The 
deposit  throughout  is  mainly  sand,  but  some  gravel  was  encountered. 
Shells  of  Unios  and  other  mollusks  were  noted  at  frequent  intervals  through- 
out nearly  the  whole  width  of  the  deposit.  Beneath  these  beach  deposits 
there  is  everywhere  a  pebbly  blue  clay,  apparently  an  unmodified  glacial 
till.  Some  of  the  sewer  ditches  in  Hyde  Park,  west  of  Grand  Boulevard, 
have  reached  peat  deposits  below  sand,  at  a  level  a  few  feet  above  the 
lake.    Wood  has  often  been  found  in  the  sand  west  of  this  beach  in  Chicago. 

'Trans.  Royal  Soc.  Canada,  1891,  pp.  29-32,  PI.  II. 


452  THE  ILLINOIS  GLACIAL  LOBE. 

Reference  has  been  made  to  the  beachlets  which  occupy  the  intei'val 
between  the  main  beach  and  the  present  shore  of  the  lake.  These  do  not 
form  continuous  hues  around  the  head  of  the  lake,  but  those  in  the  vicinity 
of  the  Chicag'o  University  aiad  Jackson  Park  die  out  in  a  marsh  which  sets 
in  a  short  distance  south  of  the  park,  and  those  in  Lake  County,  Indiana, 
die  out  at  their  western  ends  in  a  sandy  plain  wliich  borders  Wolf  Lake, 
Lake  Calumet,  and  other  small  lakes  near  the  State  line.  This  sandy  plain 
stands  but  5  to  8  feet  above  the  lake,  and  was  apparently  an  open  bay  at 
the  time  these  bar-like  features  were  forming.  But  it  has  now  become  filled 
with  sand,  leaving  Lake  Calumet  and  the  other  small  lakes  as  its  dwarfed 
re]iresentatives.  The  beachlets  stand  only  10  to  12  feet  above  lake  level 
(except  where  coated  by  wind-drifted  sand),  and,  as  noted  above,  seem 
referable  to  the  action  of  the  present  lake  rather  than  to  Lake  Chicago. 

The  outlets  of  the  lake  at  the  time  the  Third  beach  was  forming  appear 
to  have  been  along  three  lines — the  first,  that  occupied  by  the  mouth  of  the 
Chicago  River  and  the  south  branch  of  the  Chicago  River  (reversed);  a 
second  along  the  marsh  referred  to  above  as  leading  from  the  south  part  of 
Hyde  Park  T'ownship  northwestward  between  Englewood  and  South  Lynne, 
which  connects  with  the  south  fork  of  the  Chicago  River  north  of  the  Union 
Stock  Yards;  a  third  leading  westward  from  Riverdale  along  the  Sag  out- 
let. The  broadest  of  these  outlets  is  that  leading  past  Englewood  and  the 
Union  Stock  Yards,  and  it  is  possible  that  the  other  outlets  became  nearly 
closed  by  sand  before  this  outlet  was  abandoned. 

The  altitude  of  this  beach  in  Illinois  and  Indiana  is  nowhere  more  than 
20  to  22  feet  above  the  lake,  except  where  wind  has  drifted  sand  to  higher 
levels.  The  outlet  could  not  well  have  been  cut  below  a  level  8  feet  above 
tlie  lake,  that  being  the  altitude  of  the  Chicago  Outlet  for  several  miles 
below  its  junction  with  the  present  Des  Plaines  River.  The  depth  of  the 
water  in  the  outlets  would,  therefore,  be  10  to  12  feet  or  less.  As  beaches 
are  often  built  up  to  a  height  of  4  or  5  feet  above  the  ordinary  level  of  the 
lake,  it  seems  probable  that  the  ordinary  stage  of  water  was  not  more  than 
15  feet  above  the  present  stage  of  Lake  Michigan,  thus  leaving  but  7  feet 
depth  of  water  in  the  outlet.  The  Sag  outlet  reaches  nearly  15  feet  above 
the  level  of  Lake  Michigan;  hence  it  was  probably  only  a  minor  line  of 
discharge. 

As  hinted  above,  the  reference  of  this  beacli  to  the  same  lake  which 
formed  the  higher  beaches  is  not  made  with  any  degree  of  confidence. 


THE  PRESENT  BEACH  OF  LAKE  MICHIGAK  453 

Indeed,  the  abuudaut  life  of  the  waters  which  formed  this  beach  distinguishes 
it  so  strikingly  from  the  paucity  of  life  which  characterizes  the  other  beaches 
that  a  suspicion  of  a  different  origin  at  once  arises. 

Dr.  J.  W.  Spencer  has  advanced  the  view  that  an  uplift  at  the  Niagara 
outlet  is  still  in  progress,  and  has  suggested  that  the  recession  of  the  falls 
of  Niagara  past  Johnson's  Ridge,  a  ridge  standing  higher  than  the  remainder 
of  the  gorge  and  situated  about  a  mile  north  of  the  falls,  would  have  caused 
a  temporary  partial  discharge  of  the  upper  lakes,  including  Lake  Erie,  into 
the  Mississippi,  a  discharge  which  did  not  stop  the  outflow  by  Niagara.  He 
maintains  that  when  Niagara  Falls  had  eff"ected  the  incision  through  John- 
son's Ridge,  the  level  of  Lake  Erie  fell  about  24  feet,  reaching  a  level  17 
feet  below  the  Chicago  divide,  and  thus  the  full  flow  of  the  outlet  was 
returned  to  Niagara.^ 

The  test  of  the  value  of  Dr.  Spencer's  ingenious  suggestion  lies  in  the 
occurrence  of  phenomena  immediately  south  of  Johnson's  Ridge,  which  will 
demonstrate  that  the  water  stood  at  a  level  sufficientl}"  high  to  have  caused 
outflow  from  the  Chicago  Outlet.  Such  a  stage  of  water  should  have  left 
shore  markings  there  as  well  as  on  the  plain  at  the  head  of  Lake  Michigan. 
The  view  that  an  uplift  is  still  in  progress  in  the  vicinity  of  the  Niagara 
outlet  is  apparently  sustained  b}^  recent  evidence  brought  out  by  Mr.  G.  K. 
Grilbert."  The  question  of  the  date  of  this  beach  and  of  its  relation  to 
uplifts  and  barriers  ought,  however,  to  be  left  open  until  more  complete 
evidence  is  gathered. 

THE  PRESENT  BEACH  OF  LAKE  MICHIGAN. 

Dr.  Edmund  Andrews  some  years  ago  discussed  the  present  beach  of 
Lake  Michigan  and  compared  its  strength  with  that  of  the  beaches  of  Lake 
Chicago.'  Since  his  paper  is  now  out  of  print  and  copies  of  it  are  difficult 
to  obtain,  some  of  the  computations  there  made  are  presented  below.  Dr. 
Andrews  apparently  includes  the  beachlets  between  the  Tolleston  beach 
and  the  shore  of  Lake  Michigan,  referred  to  above,  in  the  present  lake  stage. 

The  lake  is  generally  encroaching  upon  the  district  on  its  west  border 
from  the  Wisconsin  line  southward  to  Chicago,  though  piers  built  along  the 
shore  in  Chicago,  and  for  some  distance  northward,  now  prevent  further 

'  Proc.  Am.  Assoc.  Adv.  Sci.,  Brooklyn  meeting,  1894,  pp.  242,  243. 

2  Nat.  Geog.  Mag.,  Sept.,  1897,  pp.  233-247.     A  fuller  discussion  has  been  presented  by  Gilbert  in 
the  Eighteenth  Annual  Report  of  this  Survey,  Part  II,  pp.  595-647,  issued  in  1898. 
^  Trans.  Chicago  Acad.  Sci.,  Vol.  II,  1870,  pp.  1-23. 


454  THE  ILLraOlS  GLACIAL  LOBE. 

encroachment.  Along-  the  borders  of  Hyde  Park,  in  the  south  part  of  Chi- 
cago, the  lake  is  building  a  beach  and  is  tending  to  fill  in  rather  than  to 
extend  the  lake  in  that  region.  In  Indiana  the  lake  is  filling  in  rather  than 
extending  its  borders.  In  southwestern  Michigan  it  is  eroding  the  promi- 
nent parts  more  rapidly  than  the  bights,  thus  giving  the  lake  a  more  regular 
outline.  In  this  connection  it  may  be  remai-ked  that  the  tendency  generally 
is  to  remove  the  prominent  parts  and  fill  the  bights. 

Dr.  Andrews  computed  the  bulk  of  the  beach  as  follows:  For  25  miles 
west  from  Michigan  City  it  maintains  an  average  cross  section  of  about 
6,000  square  yards,  and  its  contents  are  264,000,000  CLibic  yards.  In  this 
division  the  beach  is  in  the  form  of  a  lofty  belt  of  sand  dunes,  about  one- 
third  of  a  mile  wide  and  in  places  nearly  200  feet  in  height.  In  the  next 
8  miles  west  the  beach  spreads  out  into  a  broad  belt  of  low  parallel  ridges 
about  two  miles  in  extreme  width.  This  division  has  a  cross  section  of 
about  16,000  square  yards,  after  deducting  the  sand  which  was  deposited 
by  Lake  Chicago.  Its  contents  amount  to  225,280,000  cubic  yards.  From 
the  Indiana  line,  near  Wolf  Lake,  to  Chicago  River,  a  distance  of  16  miles, 
the  sand  occupies  a  belt  estimated  to  be  7  yards  thick  on  the  shore  but 
running  out  to  a  thin  edge  at  the  average  distance  of  2,500  yards  inland. 
It  therefore  has  a  cross  section  of  8,750  square  yards  and  contains 
246,400,000  cubic  yards.  To  this  should  be  added  the  portion  of  the 
beach  under  water.  This,  taken  for  the  entire  distance  from  Chicago  to 
Michigan  City,  is  estimated  to  be  about  1,011,890,000  cubic  yards.  The 
computation  of  the  subaqueous  belt  is  as  follows:  The  sand  at  the  shore 
line  is  about  10  feet  deep,  and  it  extends  out  to  where  the  water  reaches  a 
depth  of  24  to  36  feet.  The  breadth  varies  greatly,  ranging  from  about 
1,000  yards  to  nearly  5  miles,  the  widest  part  being  at  the  head  of  the  lake. 
The  total  bulk  of  the  lake  deposits,  both  in  and  out  of  the  water,  in  the 
section  between  Michigan  City  and  the  mouth  of  Chicago  River,  is  esti- 
mated to  be  1,747,570,000  cubic  yards,  or  about  one-third  of  a  cubic  mile. 

Dr.  Andrews  estimates  that  the  combined  bulk  of  the  beaches  formed 
by  Lake  Chicago  is  nearly  equal  to  that  of  the  beach  of  the  present  lake, 
the  proportion  being  16  to  17.  In  this  computation  it  was  assumed  that 
656,000,000  cubic  j^ards,  or  nearly  one-eighth  of  a  cubic  mile,  escaped 
through  the  Chicago  Outlet.  This  assumption  is  based  on  a  comparison  of 
the  relative  sizes  of  the  beaches  of  Lake  Chicago  in  a  section  outside  the 
outlet  and  a  section  embracing  the  outlet. 


THE  PEESENT  BEACH  OF  LAKE  xMICHlGAN.  455 

Dr.  Andrews  attempted  to  estimate  the  length  of  time  involved  in  the 
accumulation  of  the  beach  deposits  by  measuring  the  amount  of  sand  carried 
southward  past  the  piers  at  Chicago  and  Michigan  City.  The  sand  aimually 
stopped  by  the  two  piers  was  found  to  be  129,000  cubic  yards.  If  this 
represented  the  whole  drift  past  the  piers,  the  period  required  for  the  accu- 
mulation of  the  sand  in  all  the  beaches  would  be  about  26,000  years  and 
the  duration  of  Lake  Michigan  at  its  present  stage  would  be  13,000  vears. 
He  estimates,  however,  that  not  more  than  one-fourth  or  one-fifth  of  the 
southward-di'ifting  sand  is  stopped  by  the  piers,  and  thus  reduces  the  period 
to  less  than  6,000  years,  with  but  about  3,000  years  for  Lake  Michigan. 

Dr.  Andrews's  estimates  were  based  on  the  assumption  that  there  is  a 
southward-flowing  current  on  each  side  of  the  lake,  carrying  sand  to  its 
present  head.  Livestigations  made  by  the  Weather  Bureau  in  1892  and 
1893,  under  the  direction  of  Prof.  Mark  Harrington,^  led  him  to  the  conclu- 
sion that  the  currents  on  the  east  shore  in  the  southern  portion  of  the  basin 
are  northward  instead  of  southward.  He  accounts  for  the  accumulation  of 
sand  on  the  north  side  of  breakwaters  along-  this  coast  by  the  action  of  the 
surf,  in  storms  blowing  from  the  north,  which  is  more  transient  than  the  cur- 
rents proper  and  would  affect  the  southern  part  of  Lake  Michigan  only 
when  the  wind  was  in  the  north.  This  occasional  phenomenon  is  verv  effi- 
cient when  it  occurs.  He  concludes  that  the  estimates  of  time  involved  in 
the  formation  of  beaches  have  less  value  than  they  would  have  if  the  accu- 
mulation were  due  more  largely  to  lake  currents. 

Considerable  study  of  the  movement  of  water  in  Lake  Michigan  has 
been  made  by  the  Chicago  Drainage  Commission,  largely  under  the  direc- 
tion of  Professor  Cooley.  As  a  result  of  these  investigations,  which  involve 
not  only  a  study  of  bottle  papers,  but  also  a  thorough  canvass  of  the 
opinions  of  lake  captains  and  an  examination  of  breakwaters,  Cooley  has 
reached  the  conclusion  that  the  effective  work  on  the  shores  is  due  to  waves 
and  not  to  currents,  and  it  is  a  matter  of  doubt  if  this  lake  has  such  a  sys- 
tem of  currents  as  are  indicated  by  Professor  Harrington's  charts.  The 
movement  of  the  water  seems  to  depend  mainly  upon  the  wind,  but  is 
governed  to  some  degree  by  the  contours  of  the  shores.  If  the  north 
winds  prevail  for  a  few  days,  as  is  often  the  case  in  the  spring  months, 
the  surface  water  appears  to  have  a  southward  movement  throughout  the 

'  Currents  of  the  Great  Lakes  as  deduced  from  the  movemeut  of  bottle  papers  during  the  seasons 
of  1892  and  1893,  by  Mark  W.  Harrington  :  Weather  Bureau  Bulletin  B,  U.  S.  Dept.  of  Agriculture,  1894. 


456  THE  ILLINOIS  GLACIAL  LOBE. 

breadth  of  the  lake,  and  return  currents  must  be  at  some  depth.  On 
the  other  hand,  a  prevailing  south  wind,  such  as  oecui's  for  short  periods 
during-  the  summer,  will  induce  a  northward  movement  across  the  entire 
breadth  of  the  lake.  The  contours  of  the  shore  seem  to  favor  a  northward 
movement  from  direct  west  winds  in  the  north  half  and  a  southward  move- 
ment in  the  south  half  of  the  lake.  As  the  prevailing  winds  are  often  from 
the  west,  these  become  the  most  protracted  of  the  movements  of  surface 
water.  Cooley  has  found  that  breakwaters  along  the  shore  support  this 
interpretation.  In  the  southern  half  of  the  lake  they  are  largely  con- 
sti'ucted  to  protect  the  hai'bors  from  the  drift  on  the  north  side,  while  in 
the  northern  half  they  are  constructed  to  protect  them  from  drift  coming 
from  the  south.  In  view  of  this  apparently  changeable  course  of  lake 
movements,  it  seems  doubtful  if  estimates,  such  as  Dr.  Andrews  attempted, 
have  the  value  that  some  have  attached  to  them. 

Dr.  Andrews  also  made  an  estimate  of  the  ag'e  of  the  lake  from  the 
annual  amount  of  destruction  of  the  bluffs.  To  determine  the  rate  of 
erosion  on  the  west  coast  of  Lake  Michigan,  he  gathered  a  large  number  of 
observations,  mostly  derived  from  surveys,  and  after  rejecting  loose  or 
vague  estimates,  as  well  as  erosions  brought  to  notice  because  of  remark- 
able rapidity,  he  obtained  the  results  given  in  the  following  table: 

Erosion  of  the  shore  of  Lai; e  Michigan  per  annum. 

Feet. 

Evau.ston 16. 95 

Old  iiier,  2  miles  farther  north 4.90 

One  mile  farther  north 3.08 

Winnetka 4.  05 

One  mile  farther  north 6.  05 

Lake  Forest 1. 65 

Waukegan 0.00 

Two  miles  farther  north 0.  00 

State  line 16.50 

Kenosha 12.00 

Two  miles  farther  north 3. 00 

Three  miles  farther  north 12.00 

RaBiue  Point 16. 00 

Ratine 6.00 

Oak  Creek 2.00 

Oni^  mile  farther  nortli 1.60 

Milwaukee 6.  25 

Port  Washington  2.30 

One  mile  fartlier  north 1. 50 

Phwe  farther  north 3.  00 

Place  4  miles  south  of  Sheboygan 8. 00 

Sheboygan 6. 25 

Manitowor 5.00 


THE  PEBSENT  BEACH  OP  LAKE  MICHIGAIs\ 


457 


From  the  above  table  it  appears  that  the  average  erosion  in  the  portion 
of  the  shore  between  Milwaukee  and.  Manitowoc  is  4.33  feet  a  year,  while 
between  Milwaukee  and  Evanston  it  is  6.24  feet  a  year.  The  average 
erosion  of  the  two  sections  is  5.28  feet. 

A  series  of  more  careful  measurements  than  those  given  in  the  above 

table  appears  in  the  Geolog-y  of  Wisconsin  and  covers  part  of  this  section 

of  the  shore.     The  following  is  the  statement  furnished  b}"  Dr.  Lapham  to 

Professor  Chamberlin :  ^ 

Mr.  S.  G.  Knight,  of  Racine,  lias  carefully  measured  for  the  Geological  Sursey 
the  distance  from  the  nearest  section  corner  or  quarter  post  to  the  bank  of  Lake 
Michigan  along  all  the  section  lines  in  Eacine  County,  the  results  of  which,  compared 
with  the  Government  survey  made  in  1836,  are  given  in  the  following  table.  Had 
these  measurements  been  made  at  right  augles  to  the  shore  line,  the  result  would  have 
been  a  trifle  less;  but  as  some  portions  of  the  bank  have  been  artificially  i)rotected, 
we  may  assume  the  result  as  a  close  approximation  to  the  actual  amount  of  loss  during 
the  past  thirty-eight  years  in  Eacine  County.  These  measurements  will  have  their 
value  many  years  hence. 

Erosion  of  the  laJce  shore  in  Racine  County,  Wisconsin. 


Section  lines. 


1836. 

1874. 

Loss. 

Chains. 

Chains. 

Chains. 

32.70 

30.30 

2.40 

34.68 

33. 46 

1.23 

30. 18 

29.70 

0.48 

16.38 

14.60 

1.78 

10.86 

9.75 

1.11 

15.58 

14.50 

1.08 

19.39 

18.43 

0.96 

26.39 

26.39 

0.00 

16.04 

15.  47 

0.57 

31.50 

30.00 

1.50 

28.03 

26. 50 

1.53 

18.82 

18.00 

0.82 

27.80 

20.60 

6.20 

21.25 

18.00 

3.25 

32.22 

31.16 

1.66 

30.20 

23.87 

6.33 

34.85 

32.40 

2.45 

46.60 

44.73 

1.87 

North  line,  sec.  6,  T.  4,  R.  23 . . 
North  line,  sec.  7,  T.  4,  R.  23 . . 
AVest  line,  sec.  8,  T.  4,  R.  23  .. 
North  line,  sec.  17,  T.  4,  R.  23. 
West  line,  sec.  16,  T.  4,  R.  23  . 
North  line,  sec.  21,  T.  4,  R.  23 . 
West  line,  sec.  22,  T.  4,  R.  23  . 
North  line,  sec.  27,  T.  4,  R.  23. 
North  line,  sec.  34,  T.  4,  R.  23 . 
West  line,  sec.  34,  T.  4,  R.  23  . 
North  line,  sec.  4,  T.  3,  R.  23 . . 
North  ]  ine,  sec.  9,  T.  3,  R.  23 . . 
North  line,  sec.  16,  T.  3,  R.  23. 
North  line,  sec.  21,  T.  3,  R.  23. 
North  line,  sec.  28,  T.  3,  R.  23. 
West  line,  sec.  28,  T.  3,  R.  23  . 
North  line,  sec.  32,  T.  3,  R.  23 . 
South  line,  sec.  32,  T.  3,  R.  23. 


Mean  of  eighteen  places 

Same  in  feet,  126.72. 

Loss  per  annum  in  feet,  3.33. 


1.92 


'Geology  of  Wisconsin,  Vol.  11,  1877,  pp.  231,  232. 


458 


THE  ILLINOIS  GLACIAL  LOBE. 


The  following  measurements  were  made  to  ascertain  the  amount  of  the  abrasiou 
of  the  west  shore  of  Lake  Michigan,  in  Milwaukee  County,  since  the  Goverument 
survey,  made  iu  1835  and  1836 : 


Place. 


South  line,  sec.  1,  T.  5,  R.  22 . . . 
South  line,  sec.  36,  T.  6,  R.  22 . 
South  line,  sec.  24,  T.  6.  R.  22. 
South  line,  sec.  21,  T.  7,  R.  22. 
South  line,  sec.  15,  T.  7,  R.  22. 
Soutli  line,  sec.  10,  T.  7,  R.  22. 
South  line,  sec.  3,  T.  7,  R.  22 . . . 
South  line,  sec.  34,  T.  8,  R.  22. 

Mean  


1835. 


Chaint. 
45.61 
15.90 
19.29 
8.72 
5.37 
43.35 
19. 34 
22.00 


I     Annual 


Chains. 
44.50 
14.40 
18.70 
8.42 
2.82 
41.64 
17.36 
18.69 


Feel. 
1.9 
2.6 
1.0 
0.5 
4.32 
2.9 
3.33 
5.61 


2.77 


The  loss  in  other  counties  bordering  the  lake  is  less  on  the  average. 

A  few  measurements  of  the  rate  of  erosion  of  the  lake  bkiff  near  New 
Buffalo,  Michigan,  have  been  made  by  Mr.  Glavin,  formerly  county  sur- 
veyor. His  measurements  were  made  at  dates  ranging  from  1870  to  1886. 
The  land  survey  was  made  in  1829.  The  shortest  period  of  erosion  is 
therefore  forty-one  years,  and  the  longest  fifty-seven  years.  In  one  case 
(south  line  /of  sec.  8,  T.  7  S.,  R.  20  W.)  there  has  been  a  gain  where  a 
dune  has  encroached  on  the  lake. 

Erosion  of  the  lake  shore  in  Berrien  County,  Michigan. 


Locality. 


Tears  of 
erosion. 


Annual 
loss. 


On  range  line  between  Es.  20  and  21  W.,  from  quarter  post  of 

sec.  30  north  to  lake 

On  line  of  sues.  25  and  36,  T.  7  S.,  R.  21  W.,  from  quarter  post 

west  to  lake 

On  south  line  of  sec.  35,  T.  7  S.,  R.  21  W.,  from  east  end  of  line 

Tvest  to  lake 

From  quarter  post  of  sec.  17,  T.  7  S.,  R.  20  W.,  north  to  lake 

On  south  line  of  sec.  17,  T.  7  S.,  R.  20  W.,  from  (luarter  post 

west  to  lake 

Eastlineof8ec.8,T.7S.,  R.20W 

Soutli  lino  of  sec.  8,  T.  7  S.,  R.  20  W 

Nortli  line  of  see.  9,  T.  7  S.,  R.  20  W.,  from  iiuarter  post  west  to 

lake 


Jlean 


Chains. 
12.41 

34.00 

76.90 
34.00 

34.50 
34.73 
42.34 

34.00 


41 
46 

41 

43 

57 
56 
57 


Feet. 
4.68 

8.68 

2.25 
4.60 

3.20 

5.24 

-3.30 

1.  11 


3.30 


THE  PRESENT  BEACH  OF  LAKE  MICHIGA]!^.         459 

The  measurements  by  Mr.  Glavin  show  but  httle  more  erosion  than 
those  reported  by  the  Wisconsin  survey.  In  view  of  these  measurements 
the  rate  for  the  entire  shore  is  probably  scarcely  more  than  half  that  of  Dr. 
Andrews's  estimates. 

Dr.  Andrews  calls  attention  to  the  existence  of  a  submerged  terrace, 
which,  he  thinks,  furnishes  a  ready  means  for  determining-  approximately 
the  original  position  of  the  shore,  and  consequently  the  distance  which  the 
bluffs  have  receded  since  the  water  occupied  its  present  level.  Where  the 
shores  are  of  drift  clay  the  terrace  generally  has  a  breadth  of  from  2  to  6 
miles,  but  at  the  south  end  of  Lake  Michigan  it  is  nearly  10  miles.  The  west 
shore  of  Lake  Michigan  was  examined  in  some  detail  between  Chicago  and 
Manitowoc  and  the  terrace  was  found  to  have  an  average  width  of  3.98  miles. 
This  terrace  slopes  gently  outward  to  the  depth  of  about  60  feet,  when  the 
bottom  dips  more  rapidly  to  the  deep  water  of  the  basin.  It  is  thought  by 
Dr.  Andrews  to  be  the  product  of  wave  action  and  is  denominated  by  him 
the  terrace  of  erosion.  The  time  required  for  the  formation  of  this  terrace 
was  computed  by  using  the  average  width  of  the  terrace  as  a  dividend  and 
the  annual  rate  of  erosion  as  a  divisor.  As  the  outer  edge  of  the  ten-ace  is 
at  the  depth  of  60  feet,  the  position  of  the  old  shore  was  assumed  to  be  at 
a  point  where  a,  line  drawn  from  the  top  of  the  present  bluff  of  the  lake  to 
the  outer  edge  of  the  terrace  would  meet  the  surface  of  the  lake.  These 
estimates  give  the  average  position  of  the  old  shore,  a  distance  of  2.72  miles 
from  the  present  shore.  Dividing  this  distance  by  the  animal  rate  makes 
the  total  age  of  the  terrace  2,720  years,  or  a  dm-ation  nearly  the  same  as 
that  computed  by  the  drifting  of  the  sand.  If  the  rate  of  erosion  determined 
by  the  Wisconsin  survey  be  substituted,  the  age  would  be  4,708  years. 

The  estimate  based  upon  the  rate  of  erosion  of  the  shore  of  the  lake  is 
probably  much  more  reliable  than  that  based  upon  the  drifting  of  the  sand 
past  the  piers,  but  the  great  variability  in  the  height  of  the  shore  (from  10 
feet  up  to  100  feet  or  more)  and  the  variability  in  the  rate  of  recession 
(from  0  to  16.95  feet  j)er  year)  makes  it  evident  that  the  above  computation 
is  at  best  only  a  rude  approximation.  These  estimates  serve,  however,  as  a 
provisional  measurement  of  the  duration  of  this  stage  of  the  lake  and  have 
much  value  in  its  bearing  upon  the  length  of  postglacial  time.  Dr.  Andrews 
remarks  that  they  are  useful  in  showing  that  it  is  impossible  to  allow,  even 
on  the  most  liberal  estimates,  any  such  postglacial  antiquity  as  100,000 
years,  which  has  often  been  claimed. 


CHAPTER   XT  I. 

INFLUENCE  OF  THE  DRIFT  UPON  DRAINAGE  SYSTEMS  AND 

DRAINAGE  CONDITIONS. 

Tliroug-hout  almost  the  whole  extent  of  the  Wisconsin  drift  in  Illinois 
and  Indiana  the  preglacial  valleys  are  filled  so  effectually  that  the  present 
drainage  is  independent  of  them.  The  only  notable  exceptions  are  found 
in  the  lower  part  of  the  Illinois  and  Wabash  valleys.  Within  the  Wiscon- 
sin drift  the  morainic  ridges  often  constitute  water  partings,  while  the  plains 
between  them  carry  drainage  lines  having  courses  nearly  parallel  with  the 
ridges.  In  the  lowan  drift  area  and  in  the  portion  of  the  Illinoian  drift  in 
western  Illinois  and  southeastern  Iowa,  it  is  frequently  possible  to  deter- 
mine the  courses  of  preglacial  di'ainage  lines  and  of  the  divides  between 
them,  though  the  sti-eams  conform  to  preglacial  features  only  in  a  rude 
way.  In  southern  Illinois  and  southwestern  Indiana,  for  about  75  miles 
north  from  the  extreme  limits  of  glaciation,  or  to  about  the  latitude  of 
St.  Louis,  Missouri,  and  Ten-e  Haute,  Indiana,  the  drift  is  so  thin  tliat  it  has 
not  greatly  changed  the  main  arteries  of  drainage  from  the  lines  followed 
by  preglacial  streams.  The  smaller  streams,  however,  are  often  found  to 
follow  courses  independent  of  preglacial  lines,  and  the  g-reat  majoritj-  are 
only  partly  coincident  with  them.  The  influence  of  glaciation,  as  already 
noted,  has  also  extended  into  outlying  districts  and  caused  the  deflections 
of  streams  whose  lower  coui'ses  or  outlets  were  so  situated  as  to  be 
obstructed  by  the  ice  sheet  or  by  its  deposits.  The  influence  of  the  di'ift 
is,  therefore,  very  marked  in  all  parts  of  the  region  under  discussion  and 
becomes  a  question  of  importance  in  the  interpretation  of  the  drainage 
development. 

Inasmuch  as  the  influence  of  the  drift  varies  greath",  the  following 
designations  are  made,  to  indicate,  in  their  order  of  importance,  the  relative 
amounts  of  change  produced  by  it : 

(a)  New  drainage  systems. 

(l))  Major  stream  deflections. 

(c)  Minor  stream  deflections. 

(f?)  Reestablished  or  nondeflected  drainage. 

460 


THE  MISSISSIPPI  VALLEY.  461 

With  the  exception  of  drainage  systems  which  are  new  throughout,  the 
drainage  hues  often  embrace  two  or  more  of  the  phases  just  outlined..  This 
can  not,  therefore,  well  be  made  a  basis  for  classification.  A  grouping 
.about  the  main  drainage  lines  will  perhaps  best  serve  our  purpose.  The 
discussion  begins  at  the  northwest  with  the  Mississippi  Valley  and  proceeds 
south  and  east. 

THE  MISSISSIPPI  VALLEY. 

The  present  Mississippi  River  has  evidently  a  system  of  drainage  widely 
different  from  the  system  or  systems  which  were  operative  in  preglacial 
times  within  the  region  now  drained  by  it.  Besides  opening  a  new  channel 
at  each  of  the  rapids,  the  stream  apparently  is  occupying  sections  of  two  or 
more  independent  preglacial  valleys.  It  may  not  be  possible  at  present  to 
determine  what  relation  the  several  sections  sustained  to  one  another  in  pre- 
glacial time,  much  less  to  show  the  relation  to  the  great  systems  by  which 
the  interior  of  North  America  was  drained. 

ACCESSION   FEOM   THE   NORTH  (?). 

Hershey  has  recently  written  a  paper  in  which  he  maintains  that  the 
present  Mississippi  at  Dubuque  is  out  of  proportion  to  the  valley  that  it 
occupies.^  Upon  comparing  it  with  neighboring  streams  whose  sources  are 
within  the  Driftless  Area,  and  whose  valleys  are  cut  in  formations  similar  to 
those  of  the  Mississippi  at  Dubuque,  he  concludes  that  the  preglacial  stream 
flowing  past  Dubuque  could  not  have  been  larger  than  the  present  Rock 
River,  and  was  possibly  as  small  as  the  Pecatonica.  The  Mississippi  pre- 
sents bluff's  which  are  somewhat  steeper  than  those  of  tributary  valleys. 
In  many  places  they  are  perpendicular  precipices,  and  they  are  rarel)^  su.ffi- 
ciently  sloping  to  support  a  growth  of  trees.  The  tributary  valleys  exca- 
vated in  the  same  rock  formations  have  wooded  slopes,  rather  steep,  but 
rarely  bare  precipices.  Hershey  remarks  concerning  this  portion  of  the 
Mississippi:  "I  have  never  yet  come  upon  its  canyon  valley  without  being 
impressed  with  its  general  appearance  of  greater  youth  than  others  of 
apparently  the  same  system." 

'The  physiographic  development  of  the  Upper  Mississippi  Valley,  by  Oscar  H.  Hershey:  Am. 
Geologist,  Vol.  XX,  1897,  pp.  246-268. 


462  THE  ILLINOIS  GLACIAL  LOBE. 

The  precise  position  of  the  supposed  divide  is  not  given,  but  is  sug- 
gested by  Hershey  to  be  south  of  the  mouth  of  the  Wisconsin  River,  where 
the  "Mihtary  Ridge"  is  crossed  by  the  present  river.  Northward  fi-om  this 
supposed  divide  the  valley  now  occupied  by  the  Mississippi  is  thought  by 
him  to  have  been  occupied  by  a  stream  "flowing  toward  central  Minnesota 
instead  of  away  from  it." 

The  geological  date  of  the  change  is  regarded  as  somewhat  uncertain, 
though  Hershey  thinks  it  probable  that  it  occurred  during"  the  advancing 
stage  of  the  earliest  glaciation  in  the  region  to  the  north.  The  advance  of 
the  ice  sheet  into  the  lower  course  of  a  northward-flowing  stream  would 
naturally  cause  the  turning  of  the  drainage  southward  over  a  low  di^^[de. 
This  may  have  occurred  long  before  the  culmination  of  the  Kewatin  ice 
sheet  An  alternative  view,  also  suggested  by  Hershey,  refers  the  reversal 
of  drainage  to  an  uplift  of  the  northern  portion  of  the  Mississippi  Basin. 
By  either  view  the  date  of  reversal  is  placed  by  him  near  the  close  of  the 
Ozarkian  (or  post-Lafayette)  epoch  of  erosion,  rather  than  at  an  earlier 
time. 


The  preglacial  valley,  thus  enlarged  by  accession  of  waters  from  the 
north,  has  been  but  partially  filled  with  drift  as  far  south  as  Clinton,  and  is 
occupied  by  the  present  stream  except  for  a  space  of  'about  a  mile,  just 
above  Clinton,  where  a  rocky  point  on  which  the  village  of  Fulton,  Illinois, 
stands,  has  been  cut  off  from  the  Iowa  side.  The  old  valley  still  furnishes 
escape  for  flood  waters  around  the  eastern  end  of  this  rockj^  point.  These 
features  are  well  displayed  on  the  Clinton  topographic  sheet  of  this  Survey, 
which  is  here  reproduced  (PI.  XVIII).^  The  cause  for  this  course  across 
a  projecting  point  of  the  west  bluff'  is  not  easy  to  determine,  and  seems 
especially  remarkable  because  of  the  unobstructed  condition  of  tlie  old 
valley.  Before  speaking  further  concerning  the  cause,  a  similar  feature  in 
a  neighboring  township  is  considered. 

An  equally  singular  deflection  of  a  stream,  shown  also  on  PL  XVIII, 
is  found  in  the  lower  coiu'se  of  Elk  River,  which  enters  the  Mississippi 
from  the  Iowa  side  about  7   miles  above  Fulton.     The  stream  leaves  a 


'  In  tlio  inspection  of  tliis  sboet  it  is  necessary  to  allow  for  20  to  30  feet  of  loess  on  the  higher 
part  of  the  rocky  i)oint,  thus  reducing  the  rock  to  about  70  foot  above  river. 


THE  MISSISSIPPI  VALLEY.  463 

broad  valley  which  opens  southward  into  the  Mississippi,  and  passes  east- 
ward across  a  narrow  point  of  uplands  separating  this  valley  from  the 
Mississippi.  The  old  valley,  though  covered  hea^dly  with  loess,  stands  only 
40  to  50  feet  above  the  present  stream  bed,  while  the  rock  ridge  rises 
promptly  on  either  side  of  the  deflected  stream  to  a  height  of  about  100 
feet  above  the  abandoned  valley. 

The  deflections,  it  will  be  observed,  are  each  situated  near  the  margin 
of  the  Kansan  and  also  of  the  lowan  drift  of  the  western  ice  field,  as  well 
as  the  margin  of  the  Illinoian  drift  of  the  eastern  ice  field.  It  becomes,  in 
consequence,  no  easy  matter  to  decide  upon  the  influence  which  each  ice 
field  may  have  exerted  in  causing  tliese  peculiar  features.  In  the  Mississippi 
deflection  at  Fulton  the  stream  has  been  shifted  to  the  west,  as  if  due  to 
obstructions  on  the  east,  while  in  the  Elk  River  deflection  the  stream  has 
been  shifted  to  the  east,  as  if  the  obstruction  were  on  the  west.  However, 
it  is  not  certain  that  the  deflections  are  directly  due  to  ice  advances.  Upon 
examining  the  ground  with  a  view  to  interpreting  the  features,  it  apj)ears 
probable  that  encroachment  by  the  Mississippi  through  a  widening  of  the 
valley  may  in  each  case  have  so  broken  down  a  portion  of  the  crest  of  the 
narrow  dividing  ridge  that  displacement  could  have  been  brought  about  by 
only  a  slight  filling  of  the  valleys,  such  a  fiUing  perhaps  as  the  loess  pro- 
duced. It  will  be  observed  that  the  present  course  of  each  stream  is  more 
direct  than  the  old  course.  This  may  aid  in  accounting  for  their  persistence 
in  the  new  lines.     This  interpretation,  however,  is  not  wholly  satisfactory. 

DEFLECTION   PAST   THE   LECLAIKE   OR  'UPPER  RAPIDS. 

Immediately  below  Clinton  the  glacial  deposits  attain  sufficient  thick- 
ness to  completely  disarrange  the  old  drainage  and  to  render  it  very  diflicult 
to  determine  the  com-se  of  the  preglacial  stream.  A  special  stud}^  of  the 
preglacial  course  was  made  for  this  Survey  by  Prof  J.  A.  Udden,  the  main 
results  of  which  he  has  kindly  furnished  for  publication  in  this  report. 

The  present  course  across  the  rapids  has  apparently  been  selected  by 
the  Mississippi  in  preference  to  several  lines  which  had  been  opened,  and  is 
the  most  direct  of  these  lines.  The  rapids  proper  extend  from  Leclaire, 
Iowa,  down  to  Rock  Island,  Illinois,  a  distance  of  nearly  15  miles.  There 
is  a  fall  at  low  water  of  20.4  feet,  or  an  average  slope  of  about  16  J  inches 
to  the  mile.     The  rapids,  however,  do  not  present  a  uniform  slope,  but 


464  THE  ILLINOIS  GLACIAL  LOBE. 

consist  of  a  series  of  rock  barriers,  called  "chains,"  separated  hj  pools  or 
stretches  of  slack  water.  The  slope  also  is  greatest  in  the  lower  portion, 
about  half  the  fall  occun-ing  in  the  last  5  miles.  The  narrowness  of  the 
valley  in  this  new  course  is  well  shown  in  PI.  XVIII.  It  averages  scarcely 
1  mile. 

The  uplands  immediately  bordering  the  narrow  portion  of  the  ]\Iissis- 
sippi  Valley  stand  100  to  120  feet  above  the  stream.  They  carry  a  capping 
of  loess  30  or  40  feet  in  average  depth,  beneath  which  there  is  a  sheet  of 
di-ift  ranging  in  depth  from  a  mere  trace  to  75  feet  or  more.  In  the  portion 
below  the  bend,  just  south  of  Leclaire,  the  drift  extends  down  about  to  the 
level  of  the  present  river  bed,  but  from  Leclaire  northward  the  rock  rises 
50  to  75  feet  above  the  river.  The  rock  cutting  accomplished  by  the  river 
is  even  less  than  these  figures  would  indicate,  for  there  appears  to  have 
been  a  small  preglacial  stream  leading  northward  from  the  vicinity  of 
Leclaire,  whose  valley  may  have  been  widened  but  little  by  the  river,  and 
whose  rock  floor  extends  below  the  level  of  the  present  stream.  The  rock 
excavation  is,  therefore,  confined  mainly  to  a  shoi't  section  2  or  3  miles  in 
length,  in  the  Aacinity  of  Leclaire,  and  even  here  the  cutting  has  reached  a 
depth  of  scarcely  75  feet. 

One  of  the  abandoned  drainage  lines  above  referred  to,  known  as 
"Cattail  Slough,"  leads  southeastward  from  a  point  in  the  Mississippi  Valley 
opposite  Clinton,  as  shown  in  PI.  XVIII,  to  join  Rock  River  Valley  at  Erie, 
Illinois.  Another,  Meredosia  Slough,  leaves  the  Mississippi  opposite  the 
mouth  of  the  Wapsipinicon  River,  a  few  miles  below  Clinton,  and  leads 
southeastward  to  Rock  River  Valley  below  Erie.  Each  of  these  channels 
is  so  low  that  it  may  be  utilized  either  by  Rock  River  or  by  the  Mississippi 
at  flood  stages  of  those  rivers.  From  Erie  (see  PI.  XVIII)  two  channels 
lead  Avestward  to  the  Mississippi,  one  along  the  present  course  of  Rock 
River,  the  other  along  Pleasant  Valley,  which  is  nearly  parallel  with  it  on 
the  north. 

The  distance  along  the  present  course  of  the  Mississippi  from  the  north- 
west end  of  Meredosia  Slough  to  the  point  where  Pleasant  Valley  connects 
with  the  river  is  only  12  miles,  while  the  course  by  way  of  the  slough  and 
valley  is  fully  twice  that  distance.  The  course  by  way  of  Cattail  Slough 
and  Rock  River  is  also  fully  double  that  by  the  present  Mississippi.  The 
narrowness  of  the  valley  of  the  present  stream  from  Cordova  to  Hampton, 


THE  MISSISSIPPI  VALLEY.  465 

Illinois,  is  in  striking  contrast  even  with  Pleasant  Valley  and  the  portion  of 
the  Mississippi  immediatelj"  below,  though  these  valleys  are  much  narrower 
than  the  valley  above  the  point  where  this  deflection  occurs/ 

Pleasant  Valley,  as  interpreted  by  Udden,  appears  to  mark  the  line  of 
a  j)reglacial  stream  which  discharged  eastward,  can-ying  probably  the 
drainage  of  the  district  now  tributary  to  Duck  Creek,  which  enters  the 
Mississippi  opposite  the  western  end  of  this  valley.  Possibly  it  carried  the 
drainage  of  a  valley  heading  near  Fairport,  Iowa,  a  few  miles  above  Mus- 
catine, or  the  course  of  that  drainage  line  may  have  been  eastward  along 
the  present  lower  course  of  Rock  River,  reversed.  Udden  locates  the 
divide  near  Fairport  because  of  the  height  of  the  rock  bluffs  at  that  point, 
their  elevation  above  the  river  being  about  175  feet,  and  because  of  the 
eastward  slope  of  the  valley  floors  of  the  small  tributaries  of  the  Mississippi 
in  the  section  immediately  east  of  Fairport.  It  appears  from  the  study  of 
these  tributary  valleys  that  the  preglacial  rock  cutting  had  extended  nearly 
to  the  level  of  the  present  stream  before  entering  Pleasant  Valley  or  the 
lower  course  of  Rock  River  Valley.  The  principal  part  of  the  rock  cutting 
along  the  Mississippi  below  Rock  Island  has  been  in  the  immediate  vicinity 
of  Fairport,  where  for  a  space  of  perhaps  a  mile  it  may  have  reached  a 
depth  of  150  feet.  The  amount  of  rock  excavation  appears  to  be  greater 
in  the  divide  near  Fan-port  than  in  the  one  crossed  near  Leclaire,  yet  the 
rock  barrier  has  been  more  effectually  removed  at  the  Fairport  than  at  the 
Leclaire  divide.  This  may  be  due  in  part  to  the  more  yielding  nature  of 
the  rock  near  Fairport,  where  it  consists  in  the  main  of  soft  Coal  Measures, 
and  in  part  to  longer  cutting  at  Fairport. 

The  question  of  the  date  of  the  deflection  of  the  Mississippi  across 
the  Leclaire  Rapids  is  of  much  interest,  though  as  yet  a  fully  satisfactory 
solution  has  not  been  reached.  Were  the  course  of  the  present  stream  past 
Leclaire  the  only  one  to  be  considered,  a  study  of  the  work  accomplished 
by  it  might  afford  a  means  for  estimating  the  time  required  in  the  exca-s'a- 
tion  compared  with  that  of  the  excavation  of  channels  whose  date  has 
ah-eady  been  established.     But  the  fact  that  the  energies  of  the  Mississippi 

'Attention  has  already  been  called  to  a  temporary  course  of  the  Mississippi  across  eastern  Iowa, 
Ijut  this  course  seems  to  have  been  abandoned  during  if  not  prior  to  the  lowan  ice  invasion  and  did 
not  persist  so  long  as  these  courses  through  the  abandoned  channels  connecting  the  Mississijjpi  and 
Rock  River  valleys. 

MON   XXXVIII 30 


466  THE  ILLINOIS  GLACIAL  LOBE. 

have  beeu  divided  among  the  several  hues  referred  to  above  renders  it  diffi- 
cult to  estimate  the  work  accomplished.  It,  however,"-  helps  us  to  appreciate 
the  cause  for  the  exceedingly  small  amount  of  excavation  accomplished  by 
the  stream  in  its  present  course.  It  also  suggests  an  explanation  for  the 
greater  amount  of  excavation  accomplished  in  the  removal  of  the  Fairport 
divide,  since  the  entire  energies  of  the  Mississippi  appear  to  have  been 
expended  on  that  divide  throughout  the  time  since  the  course  across  the 
Leclaire  Rapids  came  into  operation.    • 

In  the  discussion  of  the  temporary  displacement  of  the  Mississippi  into 
a  course  outside  the  limits  of  the  Illinoian  drift  (which  seems  to  have 
occurred  during  the  culmination  of  the  Illinoian  invasion),  it  was  suggested 
that  the  Mississippi  may  have  maintained  its  flow  through  the  lower  courses 
of  the  Cedar  and  Iowa  rivers,  until  the  invasion  of  the  ice  from  the  west  at 
the  lowan  stage  of  glaciation  forced  it  into  a  course  farther  east.  If  this 
suggestion  proves  true,  the  establishment  of  the  present  course  of  the 
Mississippi  across  the  Leclaire  Rapids,  and  also  the  occupancy  of  the  aban- 
doned channels,  Cattail  Slough  and  Meredosia  Slough,  may  be  referred 
with  some  confidence  to  the  lowan  stage  of  glaciation.  Possibly  the  Rock 
River  drainage  had  been  opened  westward  past  Fairport  at  an  earlier  date, 
though  it  seems  quite  as  probable  that  Rock  River  would  have  connected 
either  to  the  west,  through  the  Meredosia  Slough,  with  the  Mississippi,  or 
passed  southward  into  the  Illinois,  as  it  appears  to  have  done  in  preglacial 
time.  The  complexity  of  the  channeling  is  such  as  to  demand  further  field 
examination  or  further  deliberation  before  a  satisfactory  interpretation  can 
be  set  forth. 

The  question  of  the  preglacial  course  of  the  Mississippi  below  Clinton 
remains  to  be  considered.  Udden's  special  investigation  has  led  him  to  the 
conclusion  that  the  preglacial  line  must  have  been  along  one  of  two  courses, 
either  southeastward  through  the  Meredosia  Slough  and  Green  River  Basin 
to  the  Illinois  at  the  bend  near  Hennepin,  or  directly  westward  through  the 
Wapsipinnicon  Basin  to  the  mouth  of  Mud  Creek,  and  thence  southwestward 
along  the  Mud  Creek  sag  to  the  Cedar;  thence  the  course  may  have  been 
by  way  of  the  present  Cedar  and  lower  Iowa,  or  more  directly  southward 
to  the  Mississii)pi  just  west  of  the  meridian  of  Muscatine.  Udden  has  col- 
lected well  data  along  the  Mud  Creek  sag  showing  that  a  liuried  channel 
occurs  there  whose  rock  floor  is  more  than  100  feet  below  the  level  of  the 


THE  MISSISSIPPI  VALLEY.  467 

Mississi23pi  River  at  Clinton,  and  perhaps  suflficiently  low  to  have  carried 
the  drainage  of  the  preglacial  stream  whose  valley  has  been  traced  south- 
ward to  Clinton.  The  data  are  scarcely  sufficient  to  fully  establish  the 
connection  of  this  channel  across  the  Wapsipinnicon  Basin,  for  there  are 
very  few  deep  wells  in  the  basin.  Another  featui-e  which  throws  some 
doubt  upon  this  connection  is  the  narrowness  of  the  deep  portion  of  the 
channel  along  the  Mud  Creek  sag.  The  well  data  indicate  that  its  width 
can  not  exceed  2  or  3  miles,  and  this  seems  rather  narrow  for  the  continua- 
tion of  so  broad  a  valley  as  that  above  Clinton,  a  valley  4  or  5  miles  in 
width. 

Turning  to  the  southeastward  course,  one  finds  a  broad  depression  or 
lowland  tract  leading  from  Clinton  through  to  the  Illinois  River.  This  low- 
land, except  at  the  outer  moraine  of  the  Wisconsin  di'ift  in  Bureau  County, 
stands  only  a  few  feet  above  the  level  of  the  Mississippi,  and  yet  apjDarently 
can-ies  a  heavy  accumulation  of  di-ift.  The  drift  is  largely  sand,  and  there 
has  been  no  necessity  for  sinking  wells  entirely  through  it.  They  have, 
however,  penetrated  40  to  50  feet  without  striking  rock.  The  bed  rock 
gradually  descends  from  each  side  toward  the  middle  of  the  lowland,  and 
some  of  the  creeks  coming  into  the  lowland  occupy  large  and  deep  chan- 
nels which  have  been  only  partially  filled  with  di-ift.  This  rather  throws 
the  balance  of  evidence  in  favor  of  the  view  that  the  preglacial  stream 
flowed  southeastward  into  the  Illinois. 

It  should  be  observed  that  in  case  the  southwestward  route  proves  to 
have  been  the  course  of  the  Mississi^jjji,  the  present  line  of  the  stream 
departs  from  it  only  a  few  miles  and  enters  the  same  old  A'alley  below  Musca- 
tine, which  it  occupies  above  Clinton.  But  in  case  the  southeastward  route 
proves  to  have  been  the  preglacial  course  from  Clinton,  the  preglacial  ^'allev 
above  Clinton  finds  its  continuation  down  the  Illinois  instead  of  down  the 
Mississippi,  and  the  present  Mississippi  passes  from  one  drainage  system  to 
another  in  its  course  between  Clinton  and  Muscatine. 

EEESTABLISHED   STREAM  BETWEEN  THE   UPPER   AND   LOWER   RAPIDS. 

From  tlie  city  of  Muscatine  southward  to  the  head  of  the  lower  rapids, 
12  miles  above  Keokuk,  Iowa,  the  Mississippi  River  is  flowing  through  a 
broad  preglacial  valley.  It  has  removed  the  drift  throughout  only  a  por- 
tion of  the  width  of  the  old  valley  in  the  district  between  Muscatine  and 


468 


THE  ILLIIS'OIS  GLACIAL  LOBE. 


the  mouth  of  the  Iowa  River.  But  in  the  sectiou  below  the  mouth  of  the 
Iowa,  as  far  as  the  mouth  of  Skuuk  River,  it  coincides  in  width  with  the  old 
valley.  For  a  few  miles  in  Lee  County,  Iowa,  iu  the  A-icinity  of  the  city 
of  Fort  Madison,  only  a  part  of  the  width  of  the  preglacial  valley  has  Ijeen 
"opened  (see  fig.  4),  but  just  before  entering-  the  rapids  the  present  valley 
expands  to  about  the  full  width  of  the  old  valley. 


Fig.  4. — Sketch  map  of  tLe  reg:iou  borderiug  the  lower  rapids  of  thu  JIis3issippi  Kiver. 

The  present  bed  of  the  Mississippi  is  100  feet  or  more  above  the  rock 
floor  of  the  preglacial  valley  tlu-oughout  the  entire  distance  between  Musca- 
tine and  the  lower  rapids.  A  rough  estimate  of  the  relative  sizes  of  the 
present  valley  and  the  preglacial  valley  in  this  section  sliows  the  preglacial 
valley  to  be  fully  twice  as  large  as  the  present  valley.  The  present  valley 
has  an  average  depth  of  about  15U  feet  and  an  average  breadth  of  about  6 


THE  MISSISSIPPI  VALLEY. 


469 


miles,  while  the  preglacial  valley  has  a  breadth 
ranging  from  6  to  15  miles  and  a  depth  of  about 
250  feet  below  the  level  of  the  bordering-  rock 
bluffs. 

DEFLECTION   AT   THE   LOWER   RAPIDS. 

The  preglacial  channel,  as  long  since  pointed 
out  by  Gen.  G.  K.  Warren,^  and  subsequently  elab- 
orated by  Prof  C.  H.  Gordon,^  passed  southwest- 
ward  across  southern  Lee  County,  Iowa,  entering 
the  broad  valley  of  the  Mississippi  just  above  the 
mouth  of  the  Des  Moines  River.  (See  sketch 
map,  fig.  4.)  Its  east  bluff,  as  determined  by  Gor- 
don, is  only  3  or  4  miles  west  of  the  present  stream. 
The  deflection,  therefore,  is  much  smaller  than  in 
the  case  of  the  upper  rapids.  In  its  new  course 
across  the  rapids  and  thence  west  into  the  old  val- 
ley the  channel  has  a  length  of  about  15  miles. 
The  filled  portion  of  the  preglacial  channel  west  of 
it  has  a  length  of  only  8  miles,  being-  more  direct 
than  that  of  the  new  course. 

The  preglacial  channel  has,  in  its  abandoned 
poition,  about  the  same  width  as  in  the  reestab- 
lished portions  above  and  below,  and  is  shown  by 
an  artesian  well  at  Montclare  to  reach  a  level  about 
125  feet  below  that  of  the  present  river  bed  at  the 
head  of  the  rapids.  The  accompanying-  diagram- 
matic section  (fig.  5),  prepared  by  Gordon,  sets 
forth  the  relative  size  of  the  preglacial  and  present 
valleys  and  the  position  of  this  boring.  The  depth 
of  rock"  excavation  in  the  old  channel  is  estimated 
by  Gordon  to  be  245  feet,  and  the  width  6  miles, 

'Bridging  of  the  Mississippi :  Ann.  Kept.  Ctiief  of  Engineers, 
U.  S.  Army,  1878,  Appendix  X,  pp.  916-917,  Diagram  E;  also  Dia- 
gram 1,  sheet  4. 

'Buried  river  channels  in  southeastern  Iowa :  Iowa  Geol.  Sur- 
vey, Vol.  Ill,  for  1893,  pp.  239-255,  figs.  5  and  6,  PI.  XXVI.  Published 
m  1895. 


li 


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2   P 


O  2 
"^  a> 


H  a 

M    u 


■|?ll!lo|l?|?|i0|ii 

l'|oil|l';  o|o?l»l°  ; 


'"[''I 


"I !  lol 


'1^ 


Ml  l?ll?l  I  If 
■■  li'-f"  li  |ili 


O     *      S      Se     S      S     c! 

§    o    o    o    o    o   a 


470  THE  ILLINOIS  GLACIAL  LOBE. 

while  the  new  channel  has  an  estimated  rock  excavation  ranging  from  60  to 
135  feet  in  depth  and  scarcely  IJ  miles  in  width.  Probably  the  average 
depth  of  rock  excavation  in  the  new  channel  is  less  than  100  feet. 

The  lower  rapids  have  a  length  of  11.1  miles,  the  head  being-  at  Mon- 
trose Island  and  the  foot  a  short  distance  alcove  the  river  bridge  at  Keokuk. 
From  the  foot  of  the  rapids  there  is  a  narrow  valley  leading  westward  aliout 
4  miles  to  the  broad  preglacial  valley.  The  total  descent  in  the  rapids  is 
22.17  feet,  or  very  nearly  2  feet  to  the  mile.  The  rate  of  descent,  as  in  the 
upper  rapids,  is  greatest  in  the  lower  part,  there  being  a  fall  of  about  4| 
feet  in  the  lower  mile  and  nearly  8  feet  in  the  lower  2  miles.^  Above  tliis 
part  the  fall,  though  not  uniform,  is  less  definitely  broken  into  rapids  and 
pools  than  at  the  upper  rapids.  Indeed,  there  appears  to  be  a  rock  floor 
forming  the  river  bed  throughout  the  entire  length  of  the  lower  rapids. 

A  question  of  much  importance  is  found  in  the  determination  of  the 
date  at  which  the  Mississippi  entered  upon  the  work  of  excavating  its  new 
channel  past  the  lower  rapids.  The  difficulties  attending  the  solution  of 
this  question  are  great,  and  have  been  discussed  in  a  special  paper  by  the 
writer.^  The  main  points  set  forth  in  that  pa23er  are  outlined  below.  The 
deflection  being  toward  the  east,  the  drift  filling  which  caused  the  displace- 
ment in  all  probability  took  place  as  a  result  of  the  invasion  of  the  Kewatin 
ice  field  at  the  Kansan  stage  of  glaciation.  But  it  is  not  definitel}^  settled  - 
that  the  present  course  across  the  raj^ids  was  adopted  upon  the  retirement  of 
the  Kewatin  ice,  since  there  is  a  possibility  that  the  displacement  was  farther 
to  the  east.  The  coincidence  of  the  present  course  with  the  western  border 
of  the  Illinoian  di-ift  suggests  the  question  whether  the  river  inay  not  have 
adopted  this  course  as  late  as  the  time  of  the  Illinoian  invasion. 

Attention  has  already  been  called  to  the  great  erosion  of  Kansan  diift 
along  the  Mississippi  below  the  lower  rapids  which  occm-red  prior  to  the 
valley  filling  that  seems  to  have  accompanied  the  Illinoian  stage  of  glacia- 
tion.    The  pre-IUinoian  excavation  appears  to  have  been  nearly  as  great  as 

'The  foUowiug  data  are  olitained  from  Greenleaf's  report  on  Water  Power  of  the  Mississiiipi 
and  Tributaries :  Tenth  Census  of  United  States,  1880,  Vol.  XVII,  p.  60.  "  In  tlie  first  4,1?00  feet  from 
the  lower  lock  there  is  a  rise  of  4.21  feet,  then  2.22  feet  in  the  next  3,600  feet,  aud  1.67  feet  in  tlie  suc- 
ceeding 3,600  feet  to  tlie  middle  lock,  making  the  fall  iu  ordinary  low  water  from  a  point  opposite  the 
middle  lock  to  the  foot  of  the  ra])ids  8.1  feet." 

-The  lower  rapiils  of  the  Mississippi  Elver,  by  Frank  Leverett :  .lour.  Ueol.,  Vol.  ^■I1.  1899, 
pp.  1-22. 


THE  MISSISSIPPI  VALLEY.  471 

the  post-Illinoian,  and  therefore  much  too  g'reat  to  refer  to  the  work  of  the 
Des  Moines  River.  But  while  there  seems  clear  evidence  that  the  channel 
across  the  rapids  was  begun  by  the  Mississippi  before  the  culmination  of  the 
lUinoian  invasion,  it  may  not  follow  that  it  was  occupied  by  that  drainage 
from  the  close  of  the  Kansan  invasion.  The  probable  efPect  of  the  Kansan 
invasion  would  be  to  throw  the  stream  to  the  east  of  the  preglacial  course. 
Furthermore,  since  the  ice  sheet  at  that  stage  extended  beyond  the  line  of 
the  Mississippi  at  the  lower  rapids,  the  displaced  river  would  naturally  take 
a  course  through  the  lowest  available  district  east  of  that  ice  margin.  This 
being  done,  it  may  have  persisted  in  that  course  for  some  time  after  the 
culmination  of  the  Kansan  stage  of  glaciation,  and  possibly  until  the  Illi- 
noian  invasion  crowded  it  westward  to  the  present  line.  The  amount  of 
excavation  preceding  the  culmination  of  the  Illinoian  glaciation,  however, 
favors  the  view  that  its  selection  of  the  course  across  the  lower  rapids  was 
made  soon  after  the  retreat  of  the  Kansan  ice  sheet. 

The  value  of  the  lower  rapids  as  a  chronometer  for  determining  the 
time  since  the  Kansan  invasion,  as  well  as  the  relative  dates  of  the  Kansan, 
Illinoian,  lowan,  and  Wisconsin  stages  of  glaciation  were  considered  in  the 
paper  just  referred  to,  and  the  main  difficulties  were  discussed.  One  great 
difficulty  lies  in  the  fact  that  there  was  not  a  continuous  rock  excavation. 
At  both  the  lowan  and  the  Wisconsin  stage  some  filling  occurred,  and  at 
the  Illinoian  stage  also  it  is  probable  that  the  filling  predominated  over  the 
cutting.  A  further  difficulty  is  found  in  the  fact  that  the  drainage  basin  of 
the  Mississippi  above  these  rapids  has  suffered  great  changes  in  area  since 
the  Kansan  stage  of  glaciation,  thus  greatly  affecting  the  volume  of  the 
stream.     The  work  done  at  the  rapids  may  be  roughly  stated  as  follows: 

(1)  The  excavation  (independent  of  filling  at  the  Illinoian,  lowan,  and 
Wisconsin  stages  of  glaciation,  which  was  subsequently  largely  removed) 
comprises  («)  the  removal  of  a  drift  deposit  capping  the  limestone  which 
had  an  average  depth  of  perhaps  25  feet,  a  length  of  15  miles,  and  a  width 
of  1^  miles;  (p)  the  removal  of  limestone  to  an  average  depth  of  nearly  100 
feet  for  a  length  of  at  least  12  miles  and  a  width  of  about  1^  miles.  The 
excavation  of  limestone  is  estimated  to  be  nearly  one-third  of  a  cubic  mile. 

(2)  A  filling  of  undetermined  amount,  but  apparently  not  less  than  30 
feet,  correlated  with  the  Illinoian  stage  of  glaciation,  which  is  weR  shown 
bv  the  sections  at  Warsaw  and  at  Yellow  Banks  below  the  lower  end  of  the 


472  THE  ILLINOIS  GLACIAL  LOBE. 

rapids  (discussed  on  a  preceding-  page),  and  following  this  filling  a  nearly 
complete  removal  of  it  along  the  rapids. 

(3)  The  lowan  loess  tilling,  also  of  undetermined  amount,  but  probably 
15  feet  or  more,  and  following  this  a  nearly  complete  removal  along  the 
rapids. 

(4)  The  Wisconsin  sand  filling,  which  seems  to  have  raised  the  i-iver 
bed  about  50  feet,  followed  by  a  nearly  complete  removal  along  the  rapids. 

It  would  be  very  difficult  to  estimate  the  woi'k  involved  in  filling,  even 
though  the  depth  of  filhng  in  the  vicinity  of  the  rapids  were  known.  The 
filling  is  simply  an  index  of  the  excess  of  the  material  brought  in  over  the 
transporting  power  of  the  stream.  To  properl}'  estimate  the  work  done  in 
a  stage  of  filling,  it  would  be  necessary  to  compute  the  amount  of  material 
carried  through  the  channel  as  well  as  that  deposited  in  it.  In  the  case  of 
the  lower  rapids,  it  seems  doubtful  if  such  computations  can  be  made. 

The  uncertainties  involved  in  changes  of  di'ainage  area  are  fully  as 
great  as  in  the  work  of  filling.  Some  data  showing  the  effect  of  a  chang'e 
of  volume  upon  the  gradient  of  the  river  are  cited  by  General  Warren. 
At  the  time  when  Lake  Agassiz  discharged  through  the  Mississippi  the 
sti'eam  appears  to  have  opened  its  channel  in  the  Upper  Mississippi  to  a 
depth  in  harmony  with  the  bed  of  Lake  Pepin,  ^^•llich  is  about  60  feet 
below  present  low  water.  The  lesser  volume  of  water  now  passing-  down 
the  Mississippi  has  proved  inadequate  to  remove  the  detrital  dam  built  at 
the  mouth  of  the  Chippewa  River  (which  is  at  the  lower  end  of  Lake 
Pepin),  and  thus  the  bed  has  been  raised  in  that  ^-icinitv  about  50  feet.  It 
is  thought  by  General  Warren  that  a  filling  is  now  in  progress  along  the 
gi'eater  part  of  the  Mississippi  above  Cairo  as  well  as  below,  and  that  the 
rapids  are  the  chief  places  where  a  marked  cutting  is  now  in  progress.^ 

In  view  of  all  these  qualifying  conditions,  it  seems  hazardous  to  venture 
a  comparison  of  the  work  of  the  Mississippi  at  the  lower  rapids  with  that  of 
the  streams  on  which  estimates  have  been  made,  or  at  least  to  base  definite 
conclusions  iipon  such  a  comparison. 

lu  closing  this  discussion  attention  is  called  to  the  contours  of  the  bluffs 
of  the  channel  along  the  rapids  and  to  tlie  rate  of  fall  in  the  rapids.  The 
contours  of  the  bluffs  favor  the  view  that  excavation  began  soon  after  the 

'  Bridging  of  the  Mississippi :  Anu.  Kept.  Chief  of  Engineers,  r.  S.  Army,  1878-79,  pp.  912-917. 


THE  MISSISSIPPI  VALLEY.  473 

Kansan  stage  of  glaciation,  and  has  proceeded  veiy  slowly  down  to  the 
present  stream  level.  Except  at  a  few  points  where  the  river  in  rounding- 
a  curve  is  encroaching  on  its  bluff,  the  rise  is  gradual  from  each  bank  to 
the  brow  of  the  bluff,  so  that  a  large  jDart  of  the  slopes  may  easily  be  cul- 
tivated. Although  the  bluffs  are  largely  a  firm  limestone,  they  recede 
about  as  much  as  the  bluffs  formed  in  glacial  deposits  at  the  upper  rapids. 
Their  age,  therefore,  appears  to  be  several  times  as  great  as  that  of  the 
upper  rapids. 

The  work  performed  in  cutting  away  the  rock  barrier  is  many  times 
greater  than  at  the  upper  rapids.  No  "chains"  rise  above  the  general  level, 
as  at  those  rapids,  and  the  fall  has  been  reduced  to  a  very  moderate  rate.^ 
Cutting  now  proceeds  very  slowly  at  these  rapids,  for  the  river  carries  but 
little  sediment  except  at  flood  stages,  and  these  extend  over  but  a  few  weeks 
of  the  year.  If  all  the  features  of  the  new  channel  be  considered,  together 
with  the  fact  of  the  occurrence  of  long  stages  of  interruption  from  cutting, 
there  seems  little  to  oppose  the  view  that  the  opening  or  selection  of  this 
course  may  have  been  at  so  remote  a  date  as  the  Kansan  stage  of  glaciation. 

RE|:STABLISHED   STREAM  BELOW   THE   LOWER  RAPIDS. 

The  disturbance  of  the  Mississippi  Valley  drainage  below  the  lower 
rapids  is  mainly  restricted  to  the  first  50  miles,  between  Keokuk,  Iowa,  and 
Hannibal,  Missom-i,  where  the  western  or  Kewatin  ice  field  at  the  Kansan 
stage  of  glaciation  seems  to  have  covered  the  valley  and  extended  a  few 
miles  beyond  it.  This  portion  of  the  valley  was  left  open  at  the  Illinoian 
stage  of  glaciation.  There  is,  however,  a  bare  possibility,  as  noted  above, 
that  the  Illinois  lobe  encroached  slightly  upon  the  Mississippi  Valley  just 
above  St.  Louis.  The  disturbance  of  drainage  was  but  temporary  at  either 
place,  and  the  present  river  is  fully  reestablished  in  the  preglacial  course, 
its  valley  bottoms  are  as  wide  as  those  of  the  preglacial  river  and  i-ange 
from  5  to  nearly  10  miles  in  width.  The  rock  bottom  of  the  preglacial  val- 
ley, like  that  of  the  section  above  the  rapids,  is  considerably  below  the  level 
.of  the  present  stream,  as  shown  by  the  table  presented  below. 

'  It  is  probable  that  in  the  early  part  of  the  opening  of  this  new  channel  the  gradient  was  much 
steeper  than  now,  and  possibly  falls  of  some  height  existed.  But  as  yet  few  definite  criteria  bearing 
upon  this  early  condition  of  the  valley  have  been  recognized. 


474  THE  ILLINOIS  GLACIAL  LOBE. 

DEFLECTIONS   SOUTn   OF   GLACIAL   BOUNDARY. 

It  seems  necessary  to  refer  briefly  to  two  slight  deflections  of  the  Mis- 
sissippi, one  of  which  is  below  the  hmits  of  glaciation  and  the  other  near  the 
j)oint  where  the  glacial  boundary  bears  eastward  away  from  the  Mississippi 
Valler.  The  former  is  certainly  independent  of  obstruction  by  the  ice,  and 
the  latter  may  be  also.  The  deflection  near  the  glacial  boundary  is  at 
Fountain  Blufl",  Jackson  County,  Illinois,  where  a  rocky  point  similar  to 
that  at  Fulton  has  been  cut  off'  from  the  west  bluff'.  The  broad  preglacial 
valley,  as  at  Fulton,  is  still  occupied  by  the  stream  at  flood  stages,  but  is 
much  less  direct  than  the  course  across  the  rocky  point.  In  explanation  of 
this  peculiar  feature  it  is  sug-gested  that  the  encroachments  of  the  Mississippi 
upon  the  rocky  point  had  so  broken  down  the  crest  that  a  moderate  silting 
up  of  the  valley,  which  probably  occm-red  dm-ing-  the  loess  deposition, 
enabled  the  stream  to  cross  it.  The  persistence  of  the  stream  in  this  course 
is  probably  attributable  to  the  more  direct  line  of  discharg-e.  Possibly  the 
presence  of  the  ice  in  the  valley  immediately  north  and  east  of  this  rocky 
point  was  influential  in  diverting  the  stream  across  it.  The  deflection  farther 
down  the  river  is  at  Thebes,  Illinois,  where  for  a  distance  of  about  6  miles 
the  river  is  excavating  a  new  course  across  a  rock  point  which  projects 
westward  into  Missouri.  An  inspection  of  this  district  shows  that  the  alti- 
tude of  the  rock  in  the  roek;w  point  crossed  by  the  stream  is  so  low  that  it 
is  necessary  to  assume  but  little  silting  up  of  the  preglacial  channel  to  have 
made  it  possible  for  the  stream  to  take  the  present  direct  coiu'se,  probably 
not  more  than  50  feet  above  the  present  level  of  the  river.  A  silting  of  this 
amount  may  be  supposed  to  have  occurred  during  the  loess  deposition. 

ROCK  FLOOR   AND   PRESENT   STREAM  COMPARED. 

In  this  discussion  each  of  the  preglacial  valleys  utilized  by  the  present 
Mississippi  are  included.  The  data  concerning  the  rock  floor  are  obtained 
from  well  borings  or  from  tests  for  bridges,  but  are  not  .sufficiently  full  to 
show  whether  the  lowest  part  of  the  valley  floor  has  at  any  point  been 
reached,  much  less  do  they  indicate  the  lowest  part  at  all  points.  It  seems 
probable,  however,  that  the  majority  are  in  the  deep  part,  since  they  are 
located  near  the  middle  of  the  preglacial  channel.  They  at  least  indicate 
approximately  the  depth  of  preglacial  excavation,  and  it  is  thought  that  thev 
throw  some  light  upon  the  slope  of  the  rock  bottom. 


THE  MISSISSIPPI  VALLEY. 


475 


In  the  table  which  follows  it  will  be  observed  that  the  I'ock  bottom  has 
a  lower  altitude  at  St.  Paul,  Minnesota,  than  at  several  points  farther  down 
the  present  stream,  a  feature  which  is  thought  to  sustain  the  interpretation 
made  by  Hershey,  that  a  divide  has  been  crossed  between  St.  Paul  and 
Dubuque.  In  a  paper  prepared  by  the  writer  a  few  years  ago^  this  low 
altitude  at  St.  Paul  and  vicinity  was  suggested  to  be  due  either  to  north- 
ward differential  depression  or  to  a  local  deepening,  such  as  might  have 
resulted  from  a  waterfall  or  from  subglacial  erosion  by  water  or  ice.  How- 
ever, no  evidence  of  the  operation  of  these  agencies  has  been  discovered, 
and  they  could  not  have  been  operative  within  the  Driftless  Area.  These 
suggestions  do  not,  therefore,  seem  so  pertinent  as  the  interpretation  made 
by  Hershey. 

Altitudes  of  rock  bottom  and  present  Mississippi. 


Location. 


Distance, 


Low  "water, 
above  tide. 


High  water, 
above  tide. 


Roclc  floor, 
above  tide. 


St.  Paul,  Minn 

Lake  City,  Minn 

Winona,  Minn 

Lacrosse,  Wis 

Prairie  du  Chien,  Wis 

Dubuque,  Iowa 

Sabula,  Iowa 

Fulton.  Ill 

Leclaire,  Iowa  (new  channel) 

Rock  Island,  111.  (new  channel) , 

Muscatine,  Iowa  (new  channel) 

Near  Wilton,  Iowa  (old  channel) 

Near  Muscatine,  Iowa  (old  channel) 

Mouth  of  Iowa  River 

Burlington,  Iowa 

Fort  Madison,  Iowa 


Mites. 
0 
55 
40 
20 
60 
55 
36 
16 
20 
16 
24 


Feet. 

683 
658 
639 
628 
604 
585 
572 
566 
562 
542 
.^>31 


Feet. 
702 
(?) 
656 
643 
623 
607 
592 
587 
576 
560 
547 


2 

530 

18 

523 

24 

511 

18 

502 

547 
539 
527 
518 


Feet. 
a  483 
6495 
c503 
doOi 
di92 
^453 
e429 

400± 

550 

530 

506 
/400- 
-7  388 

445— 

430— 
7(365 


oN.  H.  Winohell,  Am.  Geologist,  Aug.,  1892. 

6  Geol.  of  Minnesota,  Vol.  II,  p.  17. 

cData  furnished  by  Dr.  TJ.  S.  G-rant  in  letter. 

dChamberlin  and  Salisbury,  Sixth  Ann.  Kept.  TJ.  S.  Geol.  Survey,  p.  223 

eData  given  by  "W.  K.  Oake,  ex-mayor  of  Sabula. 

/A  well  at  this  point,  reported  by  Udden,  failed  to  reach  rock  at  elevation  400  feet  above  tide. 

g  Two  wells  in  the  valley  below  Muscatine,  reported  by  Udden,  reached  rock  at  a  level  about  142  feet  below  the 
low  water  level  of  the  Mississippi. 

AC. H.Gordon:  Geol. of  Iowa,  Vol. IH,  1893,  p.  246.  A  well  one-half  mile  north  of  Fort  Madison  reached  a  level 
about  365  feet  above  tide  without  entering  rock.  The  channel  may,  therefore,  be  deeper  than  that  shown  by  the  Fort 
Madison  wells. 


'  Jour.  Geol.,  Vol.  Ill,  1895,  pp.  740-763. 


476  THE  ILLINOIS  GLACIAL  LOBE. 

Altitudes  of  rock  bottom  and  present  Mississippi — Gontiuued. 


Location. 


Montclare,  Iowa  (old  channel) 

Montrose,  Iowa  (new  channel) 

Keokuk,  Iowa  (new  channel) 

Qnincy,  111 .  (rock  shelf) 

Hannibal,  Mo ^ 

Louisiana,  JIo 

Mouth  of  Illinois  River 

Bellefontaine,  Mo.  (on  Missouri  River) 

East  St.  Louis,  III 

East  Carondelet,  111.  (on  rock  shelf?) . . 

Fountain  Bluff,  111.  (new  channel) 

Near  Wolf  Lake,  111 

Thebes,  111.  (new  channel) 

Cairo,  111 , 


Distance,  ^^o^^f^f'  jHigh  water, 
above  tide.  ,  above  tide. 


Feet. 


Feet. 


Kock  floor, 
above  tide. 


9 
12 
38 
17 
25 
68 
17 
24 

6 

100 

15 

25 

35 


500 
477 
458 
450 
437 
403 
402 
380 
377 
313 
305 
291 
270 


514 

494 

476 

467 

453 

422 

420  J- 

414 

412 

357 

350 

339 

321 


Feet. 
fl374 

490 

475 
6413 
c362 
d380— 

(?) 
e295 
/284 

330 

300 
^255- 

280 
(?) 


a  Beck's  artesian  well,  at  Montclare ;  see  Geol.  of  Iowa,  "Vol.  Ill,  p.  247 ;  also  this  report,  fig.  5. 
b  Bridge  piers  rest  on  a  rock  shelf  35  to  40  feet  below  low  water:  Eept.  P.  S.  Army  Engineers.  1878. 
cData  concerning  channel  piers  furnished  by  W.   S.   Liiicoln,   chief  engineer  of  Wabash  Kailroad.  St.  Louis, 
Missouri. 

d  Bed  of  present  stream  is  380  feet  above  tide :  Eept.  TJ.  S.  Army  Engineers,  1878. 
e  Missouri  River  Commission,  Rept.  for  1890.     The  low-water  altitude  here  given  is  on  the  Missouri. 
/Data  concerning  depth  to  rock  at  bridge  piers  furnished  by  Robert  Moore,  C.  E.,  St.  Louis,  Missouri. 
■  fif  A  well  made  by  Bolin  Sublette  failed  to  reach  rock  at  50  feet  below  river  level. 

The  fact  that  the  rock  bottom  in  this  and  other  valleys  of  the  Upper 
Mississippi  region  lies  considerably  below  the  present  streams  has  often 
been  cited  in  evidence  of  a  great  preglacial  altitude  of  the  region.  This 
interpretation  seems  questionable,  inasmuch  as  there  appears  to  be  an 
adequate  fall  to  the  seaboard  from  the  rock  floors  of  these  ^'al]e}'s,  even 
though  the  altitude  were  no  greater  than  at  present.  In  the  ■s'alley  under 
consideration  the  rock  floor  in  the  210  miles  between  Fort  Madison,  Iowa, 
and  St.  Louis,  Missouri,  makes  a  descent  of  about  80  feet,  or  4|  inches  to 
the  mile,  and  stands  sufliciently  high  at  St.  Louis  to  maintain  a  similar  fall 
to  the  Gulf  were  a  direct  channel  to  be  opened.  A  somewhat  similar 
gradient  appears  also  to  be  maintained  in  the  portion  above  Fort  Madison. 
Although  the  gradient  is  somewhat  lower  along  the  rock  floor  than  that  of 
the  present  Mississippi,  it  is  about  as  great  as  that  of  the  present  Ohio,  which 
has  a  fall  of  but  little  more  than  5  inches  to  the  mile  in  the  967  miles  from 
Pittsburg  to  Cairo. 


MINOK  TIUBUTAEIES  OF  THE  MISSISSIPPI.  477 

The  breadth  of  the  valley  excavation  seems  also  to  support  the  view 
that  it  was  produced  under  a  moderate  or  low  rather  than  a  high  stream 
gradient.  It  seems  improbable  that  a  stream  which  was  cutting  down 
rapidly  could  have  formed  a  valley  several  miles  in  width  such  as  appears 
along  the  line  of  the  Mississippi  below  Muscatine,  or  along  the  line  of  other 
preglacial  valleys  occupied  by  the  Mississippi  above  Clinton.  So  far  as 
known,  the  preglacial  channels  under  consideration  have  furnished  no  posi- 
tive evidence  of  the  existence  of  narrow  trenches  cut  below  the  general 
level  of  their  rock  bottoms.  A  few  rock  shelves  have  been  found  extending 
out  a  mile  or  more,  as  at  Quincy  and  St.  Louis,  but  these  occur  at  points 
where  the  river  has,  in  comparatively  recent  time,  been  encroaching  upon 
the  rock  bluffs,  and  may,  therefore,  be  a  more  recent  product  than  the  deeper 
part  of  the  valle3^  In  the  present  state  of  knowledge  it  certainly  seems 
unsafe  to  cite  them  in  evidence  of  a  jjreglacial  gradation  plane  standing- 
above  a  lower  part  of  the  rock  bottom. 

MINOR  TRIBUTARIES   OF  THE  MISSISSIPPI. 

Since  the  lUinoian  invasion  encroached  only  a  few  miles  upon  the  dis- 
trict west  of  the  Mississippi  (in  the  southeastern  part  of  Iowa),  it  has  not 
greatly  influened  the  course  of  the  western  tributaries.  The  larger  western 
tributaries  in  southeastern  Iowa,  as  above  noted,  were  temporarily  deflected 
southward  along  a  course  immediately  outside  the  lUinoian  ice  border,  but 
these  have  regained  the  courses  opened  prior  to  the  Illinoian  invasion.  The 
tributaries  here  discussed  are,  therefore,  mainly  on  the  eastern  side  of  the 
Mississippi.  The  discussion  begins  in  northern  Illinois  and  the  streams  are 
taken  up  in  order  southward. 

APPLE    KIVER. 

A  few  streams  lie  wholly  within  the  driftless  poi-tion  of  northwestern 
Illinois  and  adjacent  parts  of  Wisconsin  and  may,  therefore,  be  passed  by, 
since  they  maintain  their  preglacial  courses.  It  is,  however,  necessary  to 
mention  one  stream,  Apple  River,  which  lies  almost  wholl}'  within  the  limits 
of  the  Driftless  Area,  but  which  has  receiA^ed  a  marked  accession  of  drainag-e 
because  of  the  blocking  of  a  preglacial  tributary  of  the  Pecatonica.  This 
diversion  occurs  just  below  the  village  of  Millville,  as  shown  in  PI.  XII. 
For  about  3  miles  below  Millville  the  stream  is  in  a  gorge  but  little  wider 
than  its  bed.     The  small  preglacial  Apple  River  is  then  entered. 


478  THE  ILLINOIS  GLACIAL  LOBE. 

PLUM    EIVER. 

Plum  River  lies  partly  within  the  Driftless  Area,  but  its  lower  course 
and  two  important  eastern  tributaries  traverse  glaciated  districts  on  the 
southeast  border  of  the  Driftless  Area.  By  reference  to  the  Savanna 
topographic  sheet  it  will  be  seen  that  the  stream  passes  through  a  gorge  in 
southwestern  Woodland  Township,  Carroll  County,  which  appai-ently  was 
formerly  the  site  of  a  divide  between  the  Plum  River  drainage  and  a  much 
smaller  stream  entering  the  Mississippi  at  Savanna.  The  course  of  the 
preglacial  Plum  River  was  probably  southward  through  the  glaciated  dis- 
trict, along  a  line  a  few  miles  to  the  east  of  its  present  lower  coui-se,  but  as 
yet  the  precise  location  of  the  valley  has  not  been  ascertained.  Caj-roll 
Creek,  one  of  the  principal  eastern  tributaries  of  Plum  River,  apparently 
discharged  southward  through  Johnson  Creek  Valley,  from  a  point  imme- 
diately east  of  Mount  Carroll.  It  now  passes  westward  through  a  series  of 
gorges  in  the  vicinity  of  Mount  Carroll  and  enters  a  small  preglacial  valley 
about  2  miles  west  of  that  city.  The  interval  between  Carroll  Creek  and 
Johnson  Creek  is  completely  filled  with  di-ift  for  a  distance  of  about  4  miles. 
The  di-ift  filling  terminates  abruptly  near  the  point  where  the  Chicago, 
Burlington  and  Northern  Railway  crosses  Johnson  Creek.  From  that  point 
southward  a  preglacial  valley  fully  a  mile  in  width  leads  down  to  the 
Mississippi. 

No  stream  of  consequence  enters  the  Mississippi  on  the  east  between 
Plum  River  and  Rock  River.  As  the  latter  stream  constitutes  one  of  the 
major  tributaries,  its  discussion  is  taken  up  farther  on.  We  pass,  therefore, 
to  the  district  south  of  the  mouth  of  Rock  River. 

EDWARDS   RIVEE. 

• 

Edwards  River,  a  stream  which  has  a  length  of  about  60  miles,  leads 
westward  from  Henry  County  through  Mercer  County,  Illinois,  entering 
the  Mississippi  nearly  opposite  the  mouth  of  the  Iowa  River.  Its  head- 
Avater  portion  consists  of  several  streams  which  converge  to  form  two  forks 
that  unite  in  south-central  Henry  County.  From  the  junction  of  these  two 
forks  a  remarkably  direct  westwai-d  course  is  taken,  so  that  from  points  on 
its  bluffs  views  may  be  had  for  sevei'al  miles  up  or  down  the  stream.  This 
portion  has  only  insignificant  tributaries  and  drains  a  very  narrow  belt. 
The  directness  of  its  course  and  the  narrowness  of  its  drainag-e  basin  are 


MINOR  TRIBUTARIES  OF  THE  MISSISSIPPI.  479 

due  to  peculiarities  of  drift  topography,  there  being  in  the  district  through 
which  Edwards  River  flows  a  tendency  to  slight  ridging  in  a  general  east- 
west  direction,  with  broad,  shallow  depressions  separating  the  ridges. 
Edwards  River  follows  one  of  these  depressions,  while  Pope  Creek,  which 
flows  parallel  with  it  on  the  south,  follows  a  neighboring  depression.  A 
depression  north  of  Edwards  River  differs  from  that  of  the  two  valleys  just 
mentioned  in  separating  its  waters,  a  portion  flowing  directly  west  to  the 
Mississippi  through  Copper  Creek  and  a  portion  east  and  north  into  Rock 
River  through  Mill  Creek.  None  of  these  streams,  so  far  as  the  writer  is 
aware,  reach  the  bottom  of  the  drift,  yet  it  can  not  be  assumed  that  they 
follow  preglacial  lines,  for  well  sections  indicate  that  the  ridges  and  depres- 
sions are  largely  independent  of  the  altitude  of  the  underlying  rock  surface. 

HENDERSON   RIVER. 

Henderson  River,  which  drains  much  of  northern  Henderson,  northern 
"Warren,  and  part  of  Knox  counties,  Illinois,  though  having  a  length  of 
scarcely  50  miles,  furnishes  a  discharge  through  its  numerous  branches 
for  an  area  of  fully  500  square  miles.  The  courses  of  the  main  branches 
seem  to  have  no  dependence  either  upon  the  underlying  rock  surface  or 
upon  drift  topography.  They  traverse  a  very  smooth  district  having 
gradual  westward  descent.  The  courses  of  the  several  streams  are  proba- 
bly the  result  of  slight  advantages  in  the  inclination  of  the  slopes,  at 
present  difficult  to  discern.  These  streams  have  now  in  several  instances 
cut  down  into  the  rock,  and  their  courses  seem  to  be  independent  of  pre- 
glacial lines. 

FLINT    RIVER. 

The  first  western  tributary  of  the  Mississippi  to  claim  attention  is 
Flint  River,  a  small  stream  entering  the  Mississippi  immediately  north  of 
Burlington,  Iowa.  Its  source  is  in  the  marginal  ridge  of  the  Illinoian  drift 
near  New  London,  Iowa.  The  stream  flows  thence  southeastward  to  the 
Mississippi  across  a  gradually  descending  plain.  It  appears  to  disregard 
the  courses  of  preglacial  drainage  lines,  for  in  its  upper  course  drift 
deposits  extend  in  places  to  a  depth  of  250  feet,  while  in  its  lower  course  it 
has  carved  a  channel  through  the  rock  ledges,  whose  cherty  layers  give  to 
the  stream  its  name. 


480  THE  ILLINOIS  GLACIAL  LOBE. 


LOST   CREEK. 


Lost  Creek,  a  small  westeru  tributary  of  the  Mississippi  draining  the 
eastern  portion  of  Lee  County,  Iowa,  occupies  a  valley  markedly  larger 
than  other  streams  of  its  size  which  have  cut  channels  in  the  Illinoian  drift, 
a  feature  which  appears  to  be  due  to  an  occupancy  of  the  valley  by  a 
larger  stream  than  the  present  one  prior  to  the  Illinoian  ice  invasion.  The 
present  head  of  the  stream  is  in  the  marginal  ridge  of  Illinoian  drift  near 
West  Point.  It  seems  not  improbable  that  streams  now  draining  south- 
ward through  Sugar  Creek  found  their  outlet  through  Lost  Creek  Valley 
prior  to  the  Illinoian  invasion.  The  interpretation  is  rendered  difficult 
because  of  the  interruption  made  by  the  large  stream  channel  of  the  tem- 
porary Mississippi,  a  channel  which,  as  noted  above,  governs  the  present 
di-ainage  of  the  streams  outside  the  Illinoian  drift  from  Skunk  River 
southward. 

BEAR   CREEK. 

Two  small  eastern  tributaries  of  the  Mississippi  River  remain  to  be 
considei-ed — Bear  Creek  and  Bay  Creek.  The  former  drains  the  south- 
western part  of  Hancock  and  the  northern  part  of  Adams  counties,  Illinois. 
It  has  a  widely  branching  drainage  system,  and  the  courses  of  the  several 
tributaries  were  probably  determined  by  the  slope  of  the  drift  plain.  One 
of  the  tributaries  heading  near  Sutter  leads  northeastward  for  a  few  miles 
along  "Big  Meadow  Channel,"  an  abandoned  valley  of  a  larger  stream,  but 
turns  away  from  that  valley  to  form  the  north  fork  of  Bear  Creek.  This 
north  fork  traverses  a  region  of  very  thick  drift,  yet  it  may  have  no 
dependence  on  the  course  of  preglacial  drainage,  but  the  lowei*  course  of 
Bear  Creek  evidently  follows  a  preglacial  line.  The  abandoned  valley 
just  mentioned  is  described  below. 

BAY  CREEK. 

This  stream  drains  much  of  Pike  County,  Illinois.  Its  headwater  por- 
tion leads  from  the  north  border  of  the  county  southeastward  towai'd  the 
Illinois,  following  a  sag  between  two  Illinoian  drift  ridges  and  nearly  reach- 
ing the  Illinois  River,  opposite  the  village  of  Bedford.  It  then  curves 
around  to  the  southwest,  passes  through  a  gap  in  the  rocky  ridge,  which  to 
the  north  and  south  constitutes  the  divide  between  the  Mississippi  and  the 


BIG  MEADOW  CHANNEL.  481 

Illinois,  and  enters  the  Mississippi  Valley  opposite  the  town  of  Louisiana, 
Missouri.  The  deflection  to  the  west  is  due  to  the  ridge  of  Illinoian  drift 
which  follows  the  east  border  of  the  stream  and  prevents  it  from  entering 
the  Illinois  Valley.  The  gap  through  the  rock  divide  was  apparently 
broken  down  below  the  level  of  the  di'ift-filled  districts  to  the  east  prior  to 
the  ice  invasion,  and  thus  offered  no  obstraction  to  the  westward  deflection 
of  the  di-ainage. 

There  are  several  small  creeks  entering  the  Mississippi  between  Bear 
Creek  and  Bay  Creek,  but  which  scarcely  merit  special  mention,  since  they 
usually  take  a  somewhat  direct  course  to  the  river,  following  the  slope  of 
the  drift  surface.  Those  in  Adams  and  northwestern  Pike  counties  are  in 
some  casesy deflected  slightly  by  the  drift  ridges  formed  on  the  west  border 
of  the  Illinoian  drift,  and  find  passage  to  the  river  through  gaps  in  these 
ridges.  In  Pike  and  portions  of  Adams  counties  these  creeks  in  part  follow 
preglacial  lines. 

BIG  MEADOW  CHANTSTEL. 

Under  this  name  is  discussed  a  channel  which  has  been  excavated  in 
the  Illinoian  drift  by  a  stream  which  long  since  ceased  to  flow.  The  chan- 
nel is  distinctly  traceable  in  a  course  about  S.  65°  W.  from  near  the  town  of 
Bushnell,  Illinois,  to  the  valley  of  the  Mississippi  in  western  Hancock 
County,  a  distance  of  60  miles  (see  PL  VI).  Throughout  its  entire  length 
the  valley  has  bluff-like  borders,  which  range  in  height  from  20  feet  to  about 
50  feet.  In  width  it  ranges  from  one-fourth  to  fully  one-half  mile.  Its  bot- 
tom is  underlain  by  sandy  and  gravelly  material,  apparently  alluvial,  and 
there  seems  little  question  that  it  has  been  occupied  and  formed  by  a  stream 
of  considerable  volume. 

From  near  Bushnell  the  valley  is  now  followed  westward  across 
McDonough  County  by  East  Crooked  Creek.  From  the  mouth  of  this 
stream  the  channel  continues  along  Middle  Creek  (reversed)  to  the  present 
divide  between  the  Illinois  and  Mississippi  drainage  systems.  In  its  passage 
across  this  divide  it  has  cut  a  valley  fully  40  feet  in  depth  and  more  than 
half  a  mile  in  width.  It  is  this  portion  which  has  long  been  known  by 
the  residents  as  the  "Big  Meadow."  At  the  west  it  continues  down  Big 
Meadow  Creek  to  another  headwater  tributary  of  Bear  Creek,  and  thence 
follows  the  course  of  that  creek  (reversed)  to  the  divide  between  Bear  Creek 

>I0N  XXXVIII 31 


482  THE  ILLINOIS  (iLAOIAL  LOBE. 

and  the  Mississippi  near  Sutter.  The  valley  is  here  well  defined  and  nearly 
as  deep  as  at  the  "Big-  Meadow  divide."  From  Sutter  it  leads  down  the 
valley  of  a  small  stream  known  as  Rock  Run,  passing  throug-h  a  gap  in 
the  marginal  ridge  of  lUinoian  drift  just  before  entering  the  Mississippi 
Valley.  Tlu-oughout  this  entire  distance  of  not  less  than  50  miles  its 
course  is  remarkably  direct. 

The  precise  variations  in  the  elevation  of  its  bottom  have  not  been 
determined.  The  eastern  end  near  Bushnell,  the  "Big  Meadow  divide," 
and  the  divide  at  Sutter,  all  stand  very  nearly  650  feet  above  tide.  With 
the  exception  of  the  descent  into  the  Mississippi  Valley  west  from  Sutter, 
the  slope  of  the  valley  bottom  probably  nowhere  exceeds  5  feet  to  the 
mile,  and  is  usually  scarcely  half  that  amount. 

This  singular  valley  appears  to  find  its  parallel  in  the  valleys  accom- 
panying some  of  the  eskers,  an  instance  of  which  in  Kane  County  has 
already  been  discussed  (p.  284).  No  esker,  however,  lies  in  the  "Big 
Meadow"  Valley.  It  seems  probable  that  the  stream  which  excavated  this 
channel  was  confined  beneath  the  ice  sheet,  and  thus  held  to  a  direct  course 
across  the  low  divides  and  shallow  depressions  covered  by  the  ice.  The 
hypothesis  of  a  piracy  of  the  stream  which  formed  this  channel  by  the  two 
creeks  which  now  drain  it,  Crooked  Creek  and  Bear  Creek,  has  been  con- 
sidered and  seems  untenable.  The  valley  was  evidently  formed  by  a 
stream  lia\ang  much  larger  volume  than  either  of  these  creeks  possesses 
at  the  points  where  they  depart  from  this  old  channel.  Furthermore,  the 
course  of  the  channel  is  such  as  can  scarcely  be  supposed  to  have  been 
inaugurated  without  the  confining  influence  of  the  ice  sheet,  for  the  present 
courses  of  drainage  are  determined  by  the  general  slopes  of  the  region  and 
are  the  natural  lines  of  discharge.  It  seems,  necessary,  therefore,  to  refer 
this  abnormal  drainage  to  a  subglacial  stream. 

In  this  connection  it  may  be  remarked  that  the  s}^steni  of  parallel 
streams  in  McDonough  County,  all  bearing  west-southwest,  may  have  been 
a  result  of  slight  channel  development  by  subglacial  streams  along  these 
lines.  Similarly  the  depressions  occupied  by  Edwards  River,  Pope  Creek, 
and  Copper  Creek,  in  Mercer  and  Rock  Island  counties,  may  have  been  at 
first  avenues  of  discharge  for  subglacial  waters.  There  seems,  however,  in 
this  latter  district  to  have  been  a  more  decided  development  of  ridges, 
parallel  with  the  dejjressions,  than  is  found  in  the  vicinity  of  the  "Big 
Meadow"  channel. 


INFLUENCE  OF  THE  DEIFT  UPOIS^  DRAINAGE.  483 

TtOCK  RIVER  DRAINAGE  BASIN. 

Rock  River,  which  drains  much  of  northwestern  Illinois,  has  a  length 
of  nearly  300  miles  and  a  drainage  area  of  about  11,000  square  miles. 
Nearly  half  its  length  and  more  than  half  its  di-ainage  area  are  in  Wisconsin. 
Its  general  course  is  southwest  from  southern  Wisconsin  across  northwestern 
Illinois.  From  its  source  to  Janesville,  Wisconsin,  it  traverses  a  region 
covered  by  drift  of  Wisconsin  age,  and  its  basin  is  characterized  by  extensive 
swamps  and  numerous  small  lakes.  The  drainage  appears  to  be  largely 
independent  of  preglacial  lines.  Just  above  Janesville  the  river  crosses  the 
outer  or  "Kettle"  moraine  of  the  Green  Bay  lobe,  and  soon  enters  a  broad 
preglacial  valley  filled  with  a  gravel  deposit  which  heads  in  that  moraine. 
The  bordering  uplands  are  covered  by  drift  of  lowan  age,  as  well  as  by 
earlier  glacial  deposits  of  Illinoian  and  possibly  of  still  greater  age.  Below 
Janesville,  with  the  exception  of  a  few  miles  near  its  mouth  in  Rock  Island 
County,  Illinois,  the  present  stream  lies  within  the  limits  of  the  lowan  drift. 
The  western  boi'der  of  that  drift,  however,  extends  but  a  few  miles  west  of 
the  stream  at  any  point,  and  for  a  few  miles  below  Rockford  follows  nearly 
the  course  of  the  river.  The  portion  of  this  drainage  basin  lying  outside 
the  Wisconsin  drift  is  generally  undulating  and  well  drained,  but  extensive 
swamps  occur  along  Green  River,  an  eastern  tributary.  The  western 
tributaries  lie  mainly  outside  the  limits  of  the  lowan,  and  the  chief  tribu- 
tary, Pecatonica  River,  drains  a  small  part  of  the  Driftless  Area. 

The  preglacial  valley  entered  by  Rock  River  near  Janesville,  Wiscon- 
sin, is  followed  southward  a  distance  of  50  miles  to  the  mouth  of  Kishwau- 
kee  River,  a  few  miles  below  Rockford,  Illinois.  The  river  and  valley 
there  part  company,  the  valley  continuing  southward  and  apparently  con- 
necting with  the  Illinois  at  Hennepin,  the  river  turning-  southwestward  to 
enter  the  Mississippi  (see  PL  XII).  In  this  southwestward  course  is  found 
a  series  of  small  valleys  separated  by  low  divides  which  afforded  the  stream 
a  means  of  escape  without  producing  a  great  amount  of  rock  excavation,  as 
will  appear  from  the  detailed  description  given  below. 

THE    PREGLACIAL    DRAINAGE. 

The  preglacial  valley  entered  by  Rock  River  near  Janesville  may  be 
traced  without  difficulty  as  far  south  as   Rochelle,  in  southeastern  Ogle 


484  THE  ILLINOIS  GLACIAL  LOBE. 

County,  where  a  bulky  moraine  wliicli  forms  the  west  border  of  the  Wis- 
consin drift  makes  further  tracing  difficult.  The  valley  has  been  so  incom- 
pletely filled  outside  the  limits  of  the  Wisconsin  di-ift  that  its  rock  bluffs  rise 
perceptibly  above  the  general  level  of  the  filling  along  the  valley.  But 
within  the  limits  of  the  Wisconsin  drift  the  valley  has  not  only  been  com- 
pletely filled  but  the  general  level  of  the  drift  surface  rises  100  feet  or  more 
above  its  bluffs.  Its  course  can  be  known,  therefore,  only  through  data 
obtained  by  deep  borings.  These  indicate  that  it  leads  southwestward 
across  eastern  Lee  and  northeastern  Bureau  counties  to  Princeton,  and 
thence  southward  to  the  bend  of  the  Illinois  River  at  Hennepin. 

The  breadth  of  the  valley,  in  the  portion  exposed  to  view,  averages 
about  3  miles,  though  it  in  places  reaches  nearly  5  miles.  Its  rock  bottom 
appears  to  be  somewhat  lower  than  that  of  the  preglacial  valley  occupied 
by  the  neighboring  portion  of  the  Mississippi.  Chamberlin  reports  a 
boring  at  Lake  Koshkonong,  Wisconsin,  which  failed  to  reach  rock  at  an 
elevation  only  450  feet  above  tide.  The  rock  was  reached  on  the  Missis- 
sippi in  the  same  latitude  at  about  490  feet.  Borings  at  Princeton,  Peiai, 
Bureau  Junction,  and  Putnam,  Illinois,  enter  rock  at  about  340  feet  above 
tide,  while  borings  on  the  Mississippi  at  Fort  Madison,  Iowa,  which  is  some- 
what farther  south,  reach  rock  at  about  365  feet,  though  one  boring  failed 
to  reach  the  rock  at  that  elevation.  No  borings  have  been  made  between 
Lake  Koshkonong  and  Princeton  which  are  calculated  to  test  the  depth 
of  the  preglacial  valley.  Borings  at  Janes-^lle,  Wisconsin,  and  Rockford, 
Illinois,  made  at  the  foot  of  the  west  bluff,  enter  rock  at  about  530  feet 
above  tide.  They  can  scarcely  be  supposed  to  represent  the  deptli  along 
the  middle  of  the  valley  opposite  these  cities.  Several  wells  have  been 
smik  in  eastern  and  southern  Lee  County  and  in  northeastern  Bureau 
County,  Illinois,  which  fail  to  enter  rock,  though  they  terminate  at  an  eleva- 
tion less  than  500  feet  above  tide.  From  the  data  at  hand  it  appears  that 
the  rock  bottom  descends  from  450  feet  or  less  above  tide  in  southern 
Wisconsin  to  340  feet  above  tide  at  the  bend  of  the  Illinois,  90  to  100  miles 
farther  south. 

Several  of  the  large  preglacial  tributaries  of  the  old  valley  may  be 
traced  readily  in  tlie  district  lying  outside  the  limits  of  the  Wisconsin  drift. 
The  Pecatonica  River,  which  is  the  largest  of  the  present  tributaries,  is 


EOCK  EIVEE  DEAINAGE  BASIN.  485 

reestablished  along  the  preglacial  line,  though  the  lower  half  of  its  course 
lies  within  the  limits  of  the  glacial  district.  The  headwater  portion  of  one 
of  the  western  tributaries  of  the  Pecatonica — Yellow  Creek — has  been 
diverted  into  Apple  River,  a  tributar}^  of  the  Mississippi.  This  stream  also 
makes  slight  deflections  into  the  bordering  bluifs  in  its  lower  course.  Sugar 
River,  the  principal  northern  tributary  of  the  Pecatonica,  occupies  its  pre- 
glacial line,  except,  perhaps,  at  the  headwaters.  Many  of  the  smaller  trib- 
utaries are  also  largely  in  preg'lacial  lines. 

Leaf  River,  which  now  drains  a  portion  of  northern  Ogle  County 
eastward  into  Rock  River,  is  following  a  preglacial  line  which  continued 
eastward  across  the  present  course  of  Rock  River,  through  an  abandoned 
channel  known  as  "Stilhnan  Valley,"  to  the  village  of  Stillman  Valley,  and 
thence  northeastward  to  the  old  Rock  River  Valley  in  southern  Winnebago 
County.  Rock  River  follows  the  line  of  this  preglacial  valley  for  a  few 
miles  in  the  vicinity  of  Byron,  but  in  the  reverse  direction  from  the  stream 
which  excavated  the  valley.  Rock  River  also  makes  use  of  small  tribu- 
taries of  the  preglacial  Leaf  River.  From  the  mouth  of  the  present  Leaf 
River  it  passes  up  the  valley  of  a  small  southern  tributary  for  a  few  miles. 
Before  entering  the  old  Leaf  River  Valley  east  of  Byron  it  has  utilized  a 
small  northern  tributary  of  that  valley.  Bluff  Creek  also,  which  enters 
the  present  Rock  River  a  few  miles  above  Byron,  has  a  preglacial  course 
southeastward  across  the  present  Rock  River  to  a  lower  course  of  the  ]3re- 
glaciai  Leaf  River. 

The  Kishwaukee  River,  the  first  important  eastern  tributary  of  Rock 
River  south  of  the  Wisconsin  line,  is  in  a  new  course  for  a  few  miles  below 
the  junction  of  the  north  and  south  branches.  It  is  not  clear  whether  the 
old  mouth  was  a  short  distance  north  of  the  present  mouth  or  whether  the 
stream  passed  southward  up  the  south  branch  to  the  vicinity  of  Fielding 
and  thence  across  to  the  old  Rock  River  Valley  near  Esmond.  The  north 
and  south  branches  each  occupy  a  preglacial  valley  for  a  few  miles  above 
their  junction,  but  the  headwater  portions  of  each  stream  are  in  new  val- 
leys. The  head  of  the  north  fork  may  not  have  been  so  far  east  as  now, 
for  the  effect  of  the  ice  sheet  generally  in  northern  Illinois  has  been  to  force 
streams  into  the  Rock-Illinois  drainage  basin  from  the  east  slope  of  the 
limestone  ridge  which  separated  this  basin  from  the  Lake  Michigan  Basin. 


486  THE  ILLINOIS  GLACIAL  LOBE. 

Kite  River,  which  now  flows  northwestward  into  Rock  River  at  Ore- 
gon, Illinois,  occupies  a  preglacial  western  tributary  of  the  old  Rock  River 
which  may  be  traced  southeastward  into  the  old  valley  at  a  point  south  of 
Rochelle.  The  head  of  the  preglacial  stream  appears  to  have  been  in  the 
hills  back  of  the  town  of  Oregon.  The  present  Rock  River  therefore  cuts  off 
only  the  headwater  portion  of  this  preglacial  valley. 

The  preglacial  drainag-e  of  southern  Ogle,  northern  Lee,  and  eastern 
Whiteside  counties  appears  to  have  been  directly  toward  the  preglacial 
Rock  River  in  southern  Lee  and  northern  Bureau  counties.  The  jjresent 
Rock  River  intersects  several  of  these  streams  midway  of  their  course  and 
diverts  them  westward  into  the  Mississippi.  The  lower  courses  of  these 
preglacial  streams  are  now  concealed  beneath  the  sand  deposits  of  the 
Green  River  Basin.  Probably  western  Whiteside  and  neighboi'ing  portions 
of  Henry  and  Rock  Island  counties,  now  tributary  to  Rock  River,  were 
tributary  to  a  jireglacial  stream  which  connected  directly  with  the  Mississippi, 
if  they  did  not  themselves  discharge  directly  into  the  stream. 

PRESENT   COURSE   OF   ROCK   RIVER. 

At  the  mouth  of  the  Kishwaukee  River,  7  miles  south  of  Rockford, 
Rock  River  turns  directly  away  from  the  broad  preg'lacial  valley  and  for 
50  miles  takes  its  course  southwestward  through  a  much  narrower  A-allev 
(see  PI.  XII).  The  narrow  valley  extends  to  western  Lee  County,  a  few 
miles  below  the  city  of  Dixon.  From  this  point  to  the  Mississippi,  a  dis- 
tance of  about  80  miles,  the  river  flows  in  the  broad  lowland  known  as  the 
Green  River  Basin.  A  few  miles  above  its  mouth,  however,  the  basin  is 
inteiTupted  by  island-like  strips  of  upland,  around  which  the  stream  takes 
its  course,  as  .shown  in  PI.  XVIII.  Its  main  channel  is  south  of  the  islands, 
the  other  channels  being  occupied  only  by  sloughs  and  sandy  plains. 

A  somewhat  detailed  study  of  the  nari-ow  portion  of  the  -valley  has 
been  made  with  a  view  to  determining  the  amount  of  rock  excavation  accom- 
plished. This  study  has  brought  to  light  an  interesting  series  of  changes  in 
drainage,  some  of  Avhicli  have  already  been  mentioned.  This  narrow 
poi'tion  is  naturally  divided  into  the  following  sections,  taken  in  order, 
beginning  at  the  point  of  deflection  from  the  preglacial  valley  and  passing 


ROCK  EIVER  DRAINAGE  BASIN. 


481 


soutliwestward.     The  length  of  each  section  and  estimated  amount  of  rock 
excavation  are  also  given : 

Table  showing  rock  excavation  in  the  new  course  of  Rock  River. 


Distance. 

Excavation. 

Miles. 

Mile-feet. 

1 

15 

3 

100 

1 

30 

3 

60 

7 

50 

3 

60 

2 

75 

7 

125 

2 

40 

20 

500 

(1)  Across  a  rock  ridge 

(2)  Up  preglacial  Bluff  Creek 

(3)  Across  a  rock  divide 

(4)  Down  nortli  tributary  of  preglacial  Leaf  River... 

(5)  Up  preglacial  Leaf  Kiver  Valley 

(6)  Up  a  south  tributary  of  preglacial  Leaf  Kiver 

(7)  Across  a  rock  divide 

(8)  Across  Kite  River  Valley  and  associated  lowlands 

(9)  Across  a  rock  divide 

(10)  Dowu  a  preglacial  valley  to  Green  River  Basin.. 

Total 


49 


1,055 


Throughout  this  narrow  portion  the  stream  maintains  a  width  of  about 
500  feet,  but  its  valley  ranges  in  width  from  1,000  feet  to  fully  a  mile.  The 
stream  makes  a  descent  of  only  60  feet,  being  680  feet  at  the  mouth  of 
Kishwaukee  River  and  620  feet  at  the  head  of  the  Sterling  rapids,  where  it 
opens  into  the  Green  River  Basin.^  So  far  as  known,  it  has  no  rock  rapids  in 
this  portion  of  its  course,  and  there  are  places  where  its  bed  lies  20  feet  or 
more  below  the  low-water  level  of  the  stream.  The  occurrence  of  these 
deep  places  along  the  river  bed  and  the  data  obtained  from  wells  along  the 
valley  indicate  that  the  rock  bottom  may  generally  lie  not  less  than  20  feet 
lower  than  the  present  stream.  It  has  seemed  necessary,  therefore,  in ' 
estimating  the  amount  of  rock  excavation,  to  assume  that  it  extended  to  this 
depth.     It  may  have  extended  even  deeper. 

Taking  up  now  the  several  parts  of  this  nan-ow  section  of  the  river, 
the  following  are  the  data  upon  which  the  estimates  of  the  rock  excavation 
accomplished  in  it  have  been  made  : 

In  the  passage  across  the  rock  ridge  between  the  preglacial  Rock  River 
and  Bluff  Creek  the  stream  has  cut  for  one-fourth  mile  at  the  crest  of  the 
ridge  to  a  depth  of  fully  70  feet  and  a  width  of  about  1,000  feet,  and 
presents  the  cross  section  shown  in  fig.  6,  No.  2,  but  on  the  slopes  of  the 


'  Computed  from  Greenleaf's  Report  in  Tenth  Census,  Vol.  XVII,  1880. 


488 


THE  ILLINOIS  GLACIAL  LOBE. 


N9  I.   PREGLAGIflL  AND  PRESENT  VALLEY 
OF  ROCK    RIVER  AT  HOCKFORD,  ILLINOIS. 


N°2-PR0FILE  AT 
COL  CROSS9D 
BYROCKRIVEH 
AT  A' PLATE  XI I 


N93.R0CK  RIVER 
IN  PREGLACIAL 
BLUFF  CREEK 
VALLEY 


rido-es  the  rock  surface  descends  to  only  20  or  25  feet  above  the  river.    The 
excavation  in  this  ridge  is,  therefore,  not  more  than  15  mile-feet.^ 

In  the  three  miles  along  the  preglacial  Bluff  Creek  the  amount  of  cut- 
ting ranges  in  depth  from  25  to  nearly  100  feet  and  in  width  from  1,500  to 

2,000  feet.  The  level  at  which  the  pre- 
glacial stream  had  cut  is  marked  by  a 
change  in  the  angle  of  slope  (see  fig.  6, 
No.  3),  that  below  being*  much  steeper 
than  that  above  the  preglacial  level.  It 
seems  safe  to  assume  100  mile-feet  of 
excavation. 

On  the  di^^de  between  Bluff  Creek 
and  the  north  tributary  of  the  preglacial 
Leaf  River  the  cutting  is  estimated  to  be 
double  that  at  the  neighboring  rock 
divide  on  the  east,  or  30  mile-feet  (see 
fig.  6,  No.  4).  It  has  a  depth  of  80  to  110 
feet  and  a  width  of  1,200  to  2,000  feet. 

Along  the  north  tributary  of  the 
preglacial  Leaf  River  the  excavation  de- 
creases from  about  80  feet  practically  to 
zero.  The  width  of  excavation  is  about 
2,000  feet,  widening  to  nearly  2,500  feet 
at  the  border  of  the  old  Leaf  River  Val- 
ley. The  excavation  is  estimated  to  be 
60  mile-feet. 

In  the  7  miles  along  the  preglacial 
Leaf  River  Valley  the  excavation  is  con- 
fined to  a  slight  cutting  of  perhaps  25 
feet  at  the  borders  of  the  preglacial  xnl- 
ley,  which  diminishes  to  zero  before 
reaching  the  middle  of  tJie  valley.  The  valley  here  is  a  mile  wide,  with 
gi-adual  rise  to  either  bluff,  as  shown  in  fig.  6,  No.  5.  The  excavation  is 
estimated  to  be  but  50  mile-feet,  which  is  proportionately  less  than  along 
any  other  part  of  this  narrow  portion  of  the  valley. 


N94.  PROFILE 
AT  COL  CROSSED 
BY  ROCK  RIVER 
flT"B'P'-*'''^>'ll 


NO5.R0CK  RIVER  IN  THE 
PREGLACIAL  LEAF  RIVER 
VALLEY  AT  BYRON, ILLINOIS. 


N96  PROFILE  AT 
COL  CROSSED 
BV  ROCK  RIVER 
AT  t:  PLATE  XII 


N''?  ROCKRIVEfl 
INTHEPREOLACIAL 
KITE  RIVER  VALLEY 
ATOREGON.ILL 


NOaPROFILEAT 
COLCDCROSSED 
BY  ROCK  RIVER 
AT''d  PLATE  XI I 


Fio.  6. — Sctitions  ; 


ro88  Kock  Kiver  Valley,  Id  unrtberu 
lUiTuns. 


'  A  inile-foot  embraces  a  block  1  mile  square  and  1  foot  thick. 


EOCK  RIVEE  DEAINAGE  BASIN.  489 

Aloug  the  south  tributary  of  Leaf  River  the  Umit.s  of  preglacial  exca- 
vation are  clearly  marked  as  on  Bluff  Creek.  The  excavation  on  Rock 
River  increases  from  25  feet  or  less  to  about  75  feet.  The  width  of  this 
portion  of  the  valley  is  about  2,000  feet.  The  excavation  is  estimated  to 
be  60  mile-feet. 

On  the  divide  between  the  preglacial  Leaf  and  Kite  rivers  the  excava- 
tion appears  to  have  ranged  from  60  feet  up  to  perhaps  125  feet  in  depth, 
and  the  width  is  somewhat  uniformly  about  2,000  feet  (see  fig.  6,  No.  6). 
The  excavation  is  estimated  to  be  75  mile-feet. 

In  the  Kite  River  Valley  and  associated  lowlands  the  excavation  appar- 
ently ranged  from  zero  to  about  50  feet  in  deptli.  In  Kite  River  Valley 
the  width  is  a  mile  or  more,  but  below  the  valley  it  is  about  2,000  feet.  An 
average  cross  section  is  shown  in  fig.  6,  No.  7,  which  is  at  Oregon.  The 
excavation  is  estimated  to  be  125  mile-feet. 

South  of  Kite  River  the  depth  of  excavation  appears  to  scarcely 
exceed  50  feet,  and  no  sharply  defined  col  could  be  found,  for,  being  in 
the  St.  Peter  sandstone  area,  the  uplands  are  very  uneven.  The  width  of 
excavation  is  2,000  to  2,500  feet,  and  the  total  excavation  is  estimated  to  be 
only  40  mile-feet.  The  profile  shown  in  fig.  6,  No.  8,  is  found  at  D, 
PI.  XII,  and  may  perhaps  cross  at  the  site  of  an  old  col. 

The  depth  of  excavation  along  the  portion  of  Rock  River  between  the 
place  shown  in  this  profile  and  the  Green  River  Basin  has  not  been  so 
carefully  computed  as  in  the  portions  above.  The  river  appears  to  follow 
the  line  of  a  small  preglacial  stream  as  far  as  the  mouth  of  Pine  Creek, 
whose  valley  has  been  somewhat  broadened  by  it.  Below  the  mouth  of 
Pine  Creek  the  preglacial  valley  has  been  widened  but  little.  The  average 
width  of  the  valley  is  about  one-fourth  mile,  and  in  places  it  reaches  nearly 
a  mile.  Such  is  the  case  at  the  sharp  bend  at  Grand  de  Tour  and  at  bends 
near  Dixon.  The  rock  excavation  may  possibly  amount  to  500  mile-feet 
in  this  lower  20  miles,  but  it  seems  as  probable  that  it  does  not  exceed  400 
mile-feet,  and  it  may  be  even  less. 

Combining  the  above  estimates,  it  appears  that  there  has  been  not 
more  than  1,055  mile-feet  of  excavation  in  the  49  miles  of  this  narrow 
section  of  the  Rock  River  Valley,  and  possibly  it  falls  below  1,000  mile-feet. 
It  may,  therefore,  be  roughly  placed  at  one-fifth  of  a  cubic  mile.  The 
present  discharge  through  this  valley,  based  upon  estimates  by  Greenleaf 
and  by  Rae,  is  somewhat  more  than  4,000  cubic  feet  per  second,  that  being 


490  THE  ILLINOIS  GLACIAL  LOBE. 

the  estimated  average  yearly  flow  past  the  city  of  Rockford.^  It  is  not 
known  whether  the  present  flow  diff'ers  widely  from  that  of  the  stream 
which  produced  this  rock  excavation,  for  the  excavation  appears  to  have 
been  practically  completed  prior  to  the  Wisconsin  stage  of  glaciation.  The 
drainage  area  and  the  rate  of  discharge  may  have  been  altered  somewhat 
as  a  result  of  the  Wisconsin  invasion.  Also  a  part  of  the  rock  cutting  may 
have  been  produced  by  a  glacial  stream  at  the  time  of  deflection.  It  is 
thought,  however,  that  the  glacial  stream  would  have  expended  its  energies 
at  the  rock  divides,  and  that  changes  in  drainage  area  are  of  minor  conse  • 
quence,  so  that  the  excavation  may  be  assumed  to  have  been  chiefly  accom- 
plished by  a  stream  similar  in  size  to  the  present  Rock  River. 

This  narrow  section  of  the  Rock  River  Valley  carries  dejDOsits  of 
glacial  gravel  which  appear  to  be  the  continuation  of  the  broad  gravel 
plain  that  leads  down  the  preglacial  Rock  River  Valley  from  the  Kettle 
moraine  of  the  Green  Bay  lobe.  This  gravel  plain  stands  about  50  feet 
above  the  present  level  of  Rock  River  at  Rockford  and  southward  from  that 
city  to  the  point  where  the  preglacial  and  present  valleys  of  Rock  River 
part  company.  It  has  no  continuation  southward  along  the  preg'lacial 
valley,  but  passes  instead  down  the  narrow  valley  of  the  present  stream. 
Its  altitude  at  Byron,  as  shown  by  the  railway  survey,  is  50  to  55  feet 
above  the  low-water  level  of  the  stream  at  that  point.  At  Oregon  its  ele- 
vation is  about  40  feet,  and  it  maintains  an  elevation  of  nearly  40  feet  from 
there  to  the  point  where  it  emerges  into  the  Green  River  Basin  above  Ster- 
ling. This  filling  apparently  began  a  few  feet  below  the  present  river  level, 
since  the  wells  made  along  the  flood  plain  encounter  gravel  to  a  depth  of 
10  to  20  feet  or  more  below  the  stream.  However,  in  places  on  the  borders 
of  the  valley  it  rests  upon  rock  at  a  level  slightly  above  the  present 
stream.  It  may  not,  therefore,  amount  to  more  than  would  be  necessary 
to  build  the  valley  up  from  its  present  level  to  a  height  of  50  feet.  Assum- 
ing this  to  be  the  case,  the  filling  will  equal  about  four-fifths  of  the  amount 
of  rock  removed  from  the  channel  prior  to  its  deposition,  or  to  about  0.16 
of  a  cubic  mile.  The  amount  deposited  in  the  50  miles  embraced  in  the 
section  of  tlie  pi-eglacial  valley  between  the  Kettle  moi'aine  and  the  head  of 
this  narrow  section  is  much  greater.  It  is  at  least  50  feet  and  may  amount 
to  75  feet  in  deiitli.     The  widtli  being   2\   miles   or   more,  it  follows  that 


■  Seveiiteeutli  Ann.  Kejjt.  U.  S.  Geol.  Survey,  Part  II,  189(5,  p)).  733,  734. 


BOOK  RIVER  DRAINAGE  BASIN.  491 

there  was  not  less  than  a  cubic  mile  deposited  in  this  section  of  the  ])re- 
glacial  valley,  and  the  amount  may  possibly  approach  2  cubic  miles. 

The  amoimt  of  excavation  accomplished  since  the  deposition  of  the 
gravel  is  remarkably  small.  The  valley  formed  subsequent  to  this  gravel 
deposition  varies  but  little  in  breadth  in  the  100  miles  from  the  Kettle 
moraine  to  the  lower  end  of  the  narrow  section.  It  is  usually  about  1,500 
feet  in  width,  and  seldom  exceeds  2,500  feet.  Its  ilood  plain  is  30  to  40 
feet  below  the  level  of  the  gravel  plain  and  its  stream  bed  about  50  feet. 
The  stream  occupies  about  one-third  the  width  of  this  postglacial  valley. 
The  amount  of  excavation  accomplished  in  the  narrow  section  under  discus- 
sion is  estimated  to  be  about  650  mile-feet,  or  slightly  more  than  half  the 
amount  of  rock  excavation  accomplished  prior  to  the  deposition  of  the 
Wisconsin  gravel. 

It  is  a  matter  of  much  interest  to  ascertain  the  relative  lengths  of  time 
involved  in  the  interglacial  rock  excavation  and  the  postglacial  gravel 
excavation.  This,  however,  must  be  left  to  more  refined  methods  than  are 
now  at  command.  It  seems  safe  to  assert  that  the  time  involved  in  the 
rock  excavation  was  longer  than  that  involved  in  the  gravel  excavation, 
though  it  must  be  borne  in  mind  that  water  may  find  passage  through  or 
over  gravel  without  disturbing  it,  where  it  might  be  cutting  rapidly  in  the 
soft  St.  Peters  sandstone  which  forms  a  portion  of  the  new  channel  of  Rock 
River.  But  the  greater  part  of  the  rock  excavation  has  been  in  limestone, 
which  would  perhaps  offer  fully  as  much  resistance  to  erosion  as  the  gravel 
deposits  which  now  line  the  valley. 

The  deflection  of  Rock  River  into  this  new  course  certainly  preceded 
•the  Wisconsin  stage  of  glaciation,  and  probably  preceded  the  lowan.  The 
completeness  of  the  removal  of  rock  barriers  along  its  new  course  and  the 
general  character  of  the  channeling  seem  to  ally  it  with  certain  rock  gorges 
found  in  portions  of  northwestern  Illinois  and  southern  Wisconshi,  west  of 
Rock  River,  which,  as  determined  by  Hershey,  were  largely  excavated 
prior  to  the  lowan  stage  of  glaciation.^  These  gorges  are  discussed  below 
and  their  relation  to  the  lowan  deposits  are  set  forth.  Furthermore,  the 
work  accomplished  elsewhere  between  the  lowan  and  Wisconsin  stages  of 
glaciation  throws  doubt  upon  the  view  that  this  channel  was  entirely 
excavated  after  the  lowan  stage  of  glaciation.     The  work  involved  in  the 


'  Pleistocene  rock  gorges  of  northwestern  Illinois,  bv  Oscar  H.  Hershey :  Am.  Geologist,  Vol. 
XII,  1893,  pp.  314-323. 


492  THE  ILLINOIS  GLACIAL  LOBE. 

channeling,  therefore,  seems  referable  mainly  to  the  interval  preceding  the 
lowan  glaciatiou,  and  only  in  small  part  to  that  succeeding  it. 

An  instance  of  a  rock  gorge  formed  subsequent  to  the  lowan  stage  of 
glaciatiou  is  found  in  the  west  part  of  the  city  of  Rockford,  where  Kent 
Creek  enters  Rock  River  over  a  series  of  cascades.  The  stage  of  excavation 
here  is  far  less  mature  than  in  the  rock  gorges  which  were  opened  between 
the  Illinoian  and  lowan  stages  or  in  the  new  course  of  the  Rock  River 
under  discussion. 

Concerning  the  lower  portion  of  the  new  course  of  Rock  River,  between 
the  city  of  Sterling  and  the  mouth  of  the  stream,  a  few  words  seem  necessary. 
The  river  enters  the  sandy  plain  known  as  the  Green  River  Basin  near  the 
city  of  Sterling,  a  j^lain  which  stands  Ijut  25  to  40  feet  above  the  stream.  In 
the  80  miles  from  Sterling  to  its  mouth  the  river  makes  a  descent  of  84  feet, 
of  which  15  feet  occur  in  passing  the  rapids  at  that  city,  and  about  25  feet 
more  in  the  18  miles  between  Sterling  and  Lyndon.  The  average  descent, 
including  the  rapids,  is  about  1  foot  to  the  mile,  or  nearly  the  same  x-ate  as  in 
the  narrow  portion  of  its  course  in  the  50  miles  above  Sterling.  This  lower 
portion  of  the  stream  is  evidently  independent  of  preglacial  lines,  for  it  fre- 
quently encounters  rock  ledges,  and  its  bed  is  entirely  floored  with  rock  for 
several  miles  in  the  vicinity  of  its  mouth.  The  Green  River  Basin  has  appar- 
ently been  deeply  filled  with  drift,  so  that  the  stream  encounters  rock  only 
in  its  passage  across  preglacial  interfluvial  tracts.  It  seems  probable  that 
the  preglacial  channels  in  this  basin  reach  a  level  100  feet  or  more  below 
the  interfluvial  tracts,  or  sufficiently  low  to  correspond  with  the  rock  bottom 
of  the  preglacial  Rock  and  Mississippi  rivers  in  neighboring  districts. 

Mvich  of  the  erosion  accomplished  by  Rock  River  in  the  Green  River 
Basin  has  occurred  since  the  Wisconsin  stage  of  glaciatiou,  for  a  large  part 
of  the  surface  gravel  and  sand  in  which  the  stream  has  its  channel  appears 
to  be  an  outwash  from  a  moraine  of  Wisconsin  age  at  the  head  of  the  basin. 
The  size  of  the  valley,  moreover,  corresponds  to  that  of  the  post- Wisconsin 
Valley  in  the  upper  portion  of  the  stream.  The  rapids  at  Sterling  also 
ally  it  with  gorges  opened  since  the  lowan,  and  are  consistent  with  a  post- 
Wisconsin  age. 

GREEN  RIVER. 

•  The  headwaters  of  this  eastern  tributary  of  Rock  River  are  found  in 
the  elevated  moraine  forming  the  border  of  the  Wisconsin  drift  in  south- 
eastern Lee  County,  Illinois,  and  standing  1)50  to  1,000  feet  above  tide. 


EOCK  GORGES  OF  NORTHWESTERN  ILLINOIS.  493 

The  several  headwater  streams  descend  rapidly  to  the  sandy  plain  outside 
the  moraine.  They  there  soon  enter  a  wet  prairie — "Inlet  Swamp" — whose 
altitude  is  about  775  feet  above  tide  and  which  covers  perhaps  16  square 
miles.  No  channel  is  maintained  across  this  prairie,  but  from  the  west  end 
of  the  pi-airie  a  stream  with  a  well-defined  channel  leads  westward  about  15 
miles  to  another  wet  prairie — "Winnebago  Swamp" — making  a  descent  of 
nearly  100  feet.  In  this  second  wet  prairie,  which  is  fully  10  miles  in 
length,  the  stream  has  only  a  poorly -defined  channel,  but  apparently  makes 
a  descent  of  several  feet.  The  western  part  of  the  prairie  is  estimated  by 
Rolfe  to  stand  only  660  feet  above  tide.  In  the  next  25  miles,  to  the  cross- 
ing of  the  Bureau-Henry  county  line,  the  stream  has  a  poorly-defined 
channel,  meandering  about  tlii'ough  a  series  of  marshes  among  sand  hills, 
but  making  a  descent  of  60  feet  (Rolfe).  lu  the  remaining  35  or  40  miles 
to  its  mouth  the  stream  falls  about  40  feet  and  maintains  a  well-defined 
channel.  In  the  lower  18  or  20  miles  (below  Geneseo)  it  has  excavated  a 
valley  fully  20  feet  in  average  depth  and  nearly  one-half  mile  in  width.  In 
this  section  of  its  course  it  is  bordered  by  uplands  which  are  far  less  sandy 
than  the  lowland  plain  known  as  the  Green  River  Basin. 

The  sand  which  covers  the  Green  River  Basin,  as  previously  indicated, 
appears  to  be  largely  an  outwash  from  the  Wisconsin  moraine.  The  chan- 
nel of  Green  River  is,  therefore,  of  post- Wisconsin  age,  although  traversing 
a  district  which  stood  outside  the  limits  of  the  ice  sheet  at  the  Wisconsin 
stage  of  glaciation.  The  trench  which  it  has  cut  below  Geneseo  is  entirely 
in  dej)Osits  of  silt  which  are  also  of  apparently  Wisconsin  age.  They  have 
an  elevation  corresponding  closely  to  that  of  the  Wisconsin  terrace  on 
neighboring  portions  of  the  Mississippi,  and  it  is  thought  that  they  are 
slack-water  deposits  connected  with  the  swollen  Mississippi  during  the  time 
in  which  it  was  building  up  the  terrace. 

ROCK  GORGES   OF  ISTORTHWESTERIS^  ILLINOIS. 

In  the  portion  of  northwestern  Illinois  lying  between  Rock  River  and 
the  border  of  the  Driftless  Area  the  drift  is  generally  so  thin  that  the  streams 
follow  in  large  part  the  preglacial  lines.  There  are,  however,  several 
instances  of  the  deflection  of  streams  into  the  edge  of  the  bluff"  or  across  a 
projecting  point  on  the  border  of  a  valley.  Such  deflections  usually  occur 
where  a  cluster  of  knolls  or  ridges  of  drift  greatly  obstruct  the  valley,  and 
they  are  usually  only  of  sufficient  length  to  pass  the  obstruction.     In  some 


494 


THE  ILLINOIS  GLACIAL  LOBE. 


cases,  however,  the  stream  is  thrown  across  the  divide  into  another  pregla- 
cial  valley.  The  streams  in  cutting  new  courses  through  the  rock  ledges 
have  found  the  material  so  resistant  that  very  narrow  channels  have  been 
formed  which,  because  of  their  narrowness  and  the  precipitous  rock  cliffs 
on  their  borders,  are  known  as  rock  gorges.  Several  of  these  rock  gorges 
in  Stephenson  County  have  been  examined  with  considerable  care  and  dis- 
cussed by  Hershey.^  His  paper  contains  the  following  table  of  measui-e- 
ments  and  estimates  of  a  few  of  these  gorges.  There  is  added  a  more 
recent  measurement  of  a  gorge  on  Carroll  Creek  just  west  of  Mount  Carroll: 

Measurements  of  rock  gorges  in  northwestern  Illinois,  by  Oscar  JS.  Hershey. 


No. 

Situation. 

Drainage 
area. 

Length. 

Breadth. 

Depth. 

Cubic  con- 
tents. 

Width 
of  bot- 
tom. 

Width 

of 
present 
stream. 

Feet. 

Ratio 
■width  of 
bottom  to 
Tridth  of 
stream. 

Sq.  miles. 

Feet. 

Feet. 

Feet. 

Cu.  yds. 

Feet. 

1 

1  mile  north,  of  Freeport. 

i 

950 

140 

29 

140,  000 

50 

5 

10       :  1 

2 

5  miles  northwest  of  Free- 
port. 

4 

850 

240 

44 

330,  000 

175 

25 

7       :  1 

3 

3  miles  south  of  Freeport. 

10 

2,050 

235 

36 

640,  000 

200 

20 

10       :  1 

4 
5 

Cedarville     ............. 

29 

1^ 

3,  250 
225 

160 
175 

57 
15 

1, 100,  000 
21,  875 

133 

150 

25 
5 

5.3  :1 

30      :  1 

Cedarville  

6 

3  miles  west  of  Freeport. 

1 

950 

100 

25 

88, 000 

80 

8 

10      :  1 

7 

4  miles  west  of  Freeport. 

5 

1,100 

165 

30 

202,  000 

145 

10 

14.  5  :  1 

8 

Carroll  Creek 

45 

2  miles. 

180+ 

50 

3, 530,  000 

180 

30 

6      :  1 

From  the  above  table  it  appears  that  the  gorg-es  show  remarkable 
variations  in  size,  the  causes  for  which  are  not  made  clear.  The  small  ratio 
of  width  of  bottom  to  width  of  stream  displayed  by  the  two  streams  hav- 
ing the  largest  drainage  area  raises  the  suspicion  that  the  smaller  streams 
may  have  had  softer  material  to  work  upon  and  thus  have  been  able  to 
accomplish  a  greater  amount  of  excavation  than  that  displayed  b)'  tlie  two 
larger  streams.  The  writer  has  had  opportunity  to  examine  onlj-  two  of 
the  gorges.  No.  1  and  No.  8  of  the  above  table.  These  gorges  are  of  some- 
what different  type.  The  gorge  No.  1,  on  the  small  stream  north  of  Free- 
port,  has  bluffs  so  broken  down  that  an  ascent  may  easily  be  made  at  almost 
any  j)oint.  As  shown  in  the  table,  the  top  of  the  gorge  has  a  breadth  nearly 
three  times  as  great  as  at  the  bottom,  though  the  gorge  is  scarcel}'  30  feet 


'  Pleistocene  rock  gorges  of  northwestern  lUinnis,  by  Oscar  11.  Her,'<hey  :  Am.  Geologist,  Vol.  XII, 
1893,  pp.  314-323. 


EOCK  GORGES  OF  NORTHWESTERN  ILLINOIS.  495 

in  depth.     But  gorge  No.  8,  on  Carroll  Creek,  has  precipitous  bluffs  which 

are  often  perpendicular  and  in  places  overhanging,  so  that  the  bottom  Avidth 

is  nearly  as  great  as  the  top  except  where  the  gorge  is  cut  largely  in  drift; 

it  there  presents  gradual  slopes.     Hershey's  measurements  of  the  gorge  at 

Cedarville  (No.  4  of  the  table)  indicate  that  it  may  be  about  as  abrupt  as 

the  gorge  on  Carroll  Creek.     He  considers  the  Cedarville  gorge  the  best 

illustration  found  in  Stephenson  County,  and  has  presented  the  following 

description  of  it.^ 

,  The  Cedarville  gorge  (No.  4  of  the  table)  may  be  takeu  as  the  type,  and  a  descrip- 
tion of  it  will  apply,  with  some  modifications,  to  all  the  others.  Cedar  Creek,  situated 
in  the  central  part  of  Stephenson  Coii'ity,  flows  in  a  general  southwest  direction  into 
Richland  Creek.  After  traversing  a  broad  valley,  with  gently  sloping  sides  covered 
with  drift  and  loess,  it  suddenly  enters  a  deep,  narrow  gorge  with  steep,  rock- bound 
walls.  The  contraction  of  the  valley  from  3,000  to  160  feet  is  conspicuous  and  readily 
attracts  attention.  The  old  valley  can  be  traced  around  by  the  south,  but  is  partially 
filled  with  sand  ridges.  The  sides  of  the  gorge  are  in  some  places  perpendicular. 
They  generally  slope  at  an  angle  of  about  30  tlegrees.  The  bottom  is  flat  and  con- 
sists of  abed  of  dark-brown  alluvium,  through  which  the  stream  meanders,  sometimes 
touching  one  side  and  sometimes  the  other,  undermining  the  walls  and  widening  the 
valley.  After  about  three-fifths  of  a  mile  the  stream  enters  a  small  preglacial  valley 
and  the  gorge  widens,  but  the  same  canyon-like  character  prevails  to  its  end.  A  small 
tributary  occupies  a  portion  of  the  old  valley,  and  when  Cedar  Creek  again  enters 
this  valley  the  significant  fact  is  learned  that  a  stream  one-tenth  as  large  as  the  main 
creek  flows  in  a  valley  ten  times  as  large. 

Hershey  has  determined  that  a  large  part  of  the  erosion  of  these  gorges, 
estimated  to  be  at  least  four-fifths,  occurred  prior  to  the  deposition  of  the 
loess  associated  with  the  lowan  drift  sheet.  The  principal  line  of  evidence 
is  found  in  the  occurrence  of  loess  within  the  gorges  near  their  bottoms. 
In  one  case  near  Freeport  a  gorge  was  abandoned  because  of  the  large 
amount  of  loess  filling,  and  the  postloessial  stream  took  a  new  course.  The 
character  of  the  evidence  is  such  that  the  conclusions  drawn  by  Hershey 
seem  fully  sustained.  Within  the  limits  of  the  Ictwan  drift  in  northwestern 
Illinois  there  are  several  instances  of  the  initiation  of  a  new  course  for' the 
stream  at  the  close  of  the  lowan  stage  of  glaciation.  The  channels  cut  by 
streams  having  this  date  are  so  much  smaller  than  the  rock  gorges  included 
in  the  above  table  that  it  is  not  difficult  to  separate  the  two  classes  of  val- 
leys. In  the  gorges  under  discussion  the  streams  not  only  flow  in  vallej's 
having  bottoms  several  times  as  wide  as  the  stream  beds,  but  so  far  as  known 
they  are  entirely  free  from  falls  or  rock  rapids.     But  in  the  sti-eams  which 

'  Loc.  cit.,  p.  316. 


496  THE  ILLINOIS  GLACIAL  LOBE. 

have  opened  new  courses  since  the  close  of  the  lowan  stage  of  glaciation 
it  is  the  rule  to  find  rock  rapids,  and  even  low  falls. 

Hershey  devotes  a  considerable  part  of  his  paj^er  to  the  discussion  of  the 
comparative  amount  of  erosion  in  these  valleys  and  those  opened  at  the  lowan 
and  Wisconsin  stag-es  of  glaciation,  and  concludes  that  the  time  required  in 
their  excavation  is  several  times  that  of  the  lowan  as  well  as  of  the  Wisconsin. 

Rock  gorges  occur  to  some  extent  along  the  valleys  of  western  Illinois 
south  of  Rock  River,  but  they  are  not  of  a  class  similar  to  those  of  north- 
western Illinois  just  discussed.  They  occur  usually  where  streams  are 
opening  a  course  entirely  independent  of  preglacial  valleys,  and  where 
after  cutting  through  the  entire  depth  of  drift  they  have  begun  the  excava- 
tion of  the  rock.  These  valleys  often  have  rocky  rapids  and  low  falls.  It 
is  difficult  to  compare  the  amount  of  work  accomplished  by  these  streams 
with  that  accomplished  by  the  streams  of  northwestern  Illinois.  The 
streams  of  western  Illinois  have  had  usually  a  large  amount  of  drift  to 
remove,  and  consequently  have  been  prevented  from  beginning  the  excava- 
tion of  the  rock  at  so  early  a  date  as  was  possible  for  streams  in  northwest- 
ern Illinois.  The  valleys  which  they  have  excavated  in  the  drift  show 
much  greater  cubic  contents  than  the  rock  gorges  of  similar  sized  streams 
of  northwestern  Illinois.  It  remains  to  be  determined  whether  the  Avork 
accomplished  in  removing  the  drift  deposits  is  sufficient  to  ofi"set  the  imma- 
ture state  of  development  on  the  rock  gorges,  or  whether  the  excavation  of 
the  rock  gorges  of  the  two  districts  began  at  different  dates.  In  western 
Illinois  the  excavation  maji  confidently  be  placed  after  the  lllinoian  ice 
invasion,  but  in  northwestern  Illinois  the  possibility  of  deflection  by  a  pre- 
Illinoian  invasion  must  be  considered. 

iIjUnois  river  drainage  basin. 

The  watershed  of  the  Illinois  River  extends  in  a  broad  band,  averaging 
100  miles  in  width,  in  a  northeast-southwest  oii-ection  directly  across  the 
center  of  Illinois.  From  the  northeastern  extremity  of  this  band  there  are 
two  projections — one  north  into  Wisconsin,  including  the  Fox  and  Des 
Plaines  basin;  the  other  east  into  Indiana,  including  the  Kankakee  and  its 
main  tributary,  the  Iroquois.  The  name  Illinois  is  applied  to  the  river 
from  the  junction  of  the  Kankakee  and  Des  Plaines.  The  western  side  of 
the  watershed  is  20  to  40  miles  in  width,  while  the  eastern  is  60  to  80  miles. 
The  entire  area  is  estimated  by  Greenleaf,  in  his  report  for  the  Tenth  Census, 


ILLINOIS  RIVEE  DRAINAGE  BASIN.  497 

to  be  about  29,000  square  miles.  An  estimate  made  by  L.  E.  Cooley,  of 
the  Chicago  Drainage  Commission,  reduces  it  to  27,914  square  miles.  The 
area  in  each  of  the  three  States  is  estimated  by  Greenleaf  to  be  as  follows: 
Illinois,  24,726  square  miles;  Wisconsin,  1,080  square  miles;  Indiana,  3,207 
square  miles.  The  drainage  areas  of  the  tributaries  given  in  order  from 
som'ce  to  mouth,  as  estimated  by  Cooley,  are  as  follows:^ 

Drainage  areas  of  tributaries  of  Illinois  River. 

Square 
miles. 

Des  Plaices  River 1,  392 

Kankakee  River 5, 146 

Aux  Sable  Creek _, 218 

Mazon  Creek 540 

Fox  River 2,700 

Covel  Creek lOO 

Vermilion  River 1,  317 

Pecnmsaugum  Creek  and  Little  Vermilion  River 165 

Bureau  Creek 480 

Sandy  Creek 147 

Crow  Creek  Ceast) 226 

Senachwine  Creek  (south) 132 

Kickapoo  Creek 310 

Mackinaw  River _ 1,  217 

Copperas  Creek 151 

Quiver  River 220 

Spoon  River 1,  870 

Sangamon  River 5^  670 

Sugar  Creek 180 

Crooked  Creek 1,385 

Indian  Creek 290 

McKees  Creek 472 

Mauvaise  Terre  Creek 275 

Big  Sandy  Creek,  etc ' .525 

Macoupin  Creek 985 

Total 26,303 

Total  area  of  Illinois  watershed _ .   27,  914 

Area  of  small  tributaries  and  slopes 1,  611 

Of  the  27  tributaries  included  in  the  above  table,  it  will  be  observed 
that  13  carry  23,699  square  miles,  or  about  85  per  cent,  of  the  drainage  of 
the  Illinois  Basin.  There  are,  in  addition  to  the  tributaries  above  sriven, 
20  more  which  are  sufficiently  large  to  have  received  names,  but  which 
have  a  combined  ch-ainage  area  of  only  1,300  square  miles.  The  remaining 
300  square  miles  are  comprised  in  the  slopes  of  the  Illinois  River  Valley 
and  the  insignificant  tributaries. 

'  Rept.  Illinois  State  Board  of  Health,  1889,  p.  68. 
MON  XXXVUI 32 


.'• 


498  THE  ILLINOIS  GLACIAL  LOBE. 

The  Illiuois  River,  as  far  down  as  Peoria,  has  its  course  through  a 
district  covered  by  drift  of  Wisconsin  age.  Below  that  city  as  far  as 
southern  Pike  County,  its  bordering-  uplands  are  coated  with  Illinoian  drift, 
and  this  is  capped  by  loess.  From  Pike  County  southward  the  uplands  on 
the  west  are  nearly  free  from  glacial  drift,  but  are  heavily  coated  with 
loess.  Those  on  the  east  have  a  moderate  amount  of  Illinoian  drift  capped 
by  loess. 

Much  of  the  Kankakee  Basin  and  the  headwater  portion  of  Fox  River 
afford  very  imperfect  drainage  and  contain  extensive  marshes.  They  also 
contain  small  lakes  and  marshy  shallow  lakes,  as  well  as  the  wet  marshy 
prairies.  Elsewhere  within  the  limits  of  the  Wisconsin  drift  the  marshes, 
bogs,  and  lakes  connected  with  the  Illinois  River  drainage  are  of  small 
extent,  but  there  is,  on  the  whole,  a  rather  imperfect  development  of  drain- 
age lines.  Often  areas  of  several  square  miles,  and  occasionally  entire 
townships,  are  without  a  well-defined  channel  for  the  discharge  of  water. 
It  is  only  by  a  judicious  system  of  ditching,  including  both  surface  ditches 
and  tile  drains,  that  this  area  has  been  brought  into  its  present  fair  condi- 
tion for  cultivation.  Much  still  remains  to  be  done  before  the  full  resources 
of  the  rich  soil  will  be  at  command. 

Within  the  portion  of  the  drainage  basin  in  which  loess  forms  the 
surface  and  Illinoian  drift  the  substratum  the  drainage  is  markedly  better 
developed  than  within  the  portion  covered  by  Wisconsin  drift.  Swamps  or 
marshes  are  of  very  limited  extent,  but  there  are  not  a  few  swales  or 
shallow  valleys  which  are  poorly  drained.  Tile  draining  is  found  very 
advantageous  on  the  level  portions  of  the  uplands,  and  the  drains  are  often 
continued  along  the  shallow  valleys  or  swales  into  the  well-defined  valleys. 

The  Illinois  Valley  is  naturally  divided  into  two  parts,  the  upper  and 
lower  Illinois.  The  upper  Illinois  comprises  the  westward-flowing  portion 
from  the  junction  of  the  Des  Plaines  and  Kankakee  down  to  the  bend 
near  Hennepin,  a  distance  of  about  50  miles ;  the  lower  comprises  the 
southward-flowing  portion  extending  from  Hennepin  to  the  mouth,  a 
distance  of  about  200  miles.  The  upper  Illinois  is  excavating  a  new  course 
and  its  bed  is  usually  on  the  rock,  while  the  lower  Illinois  occupies  a  pre- 
glacial  channel  in  which  the  rock  bottom  lies  nearly  100  feet  below  the  bed 
of  the  present  stream.     This  preglacial  channel,  as  above  indicated,  eon- 


ILLINOIS  EIVER  DEAINAGE  BASIN.  499 

stitutes  the  southward  continuation  of  the  preglacial  channel  occupied  by 
Rock  River  in  southern  Wisconsin  and  northern  lUinois. 

THE   LOWER    ILLINOIS. 

The  lower  Illinois  Valley,  as  indicated  above,  seems  to  have  been  so 
imperfectly  filled  by  glacial  deposits  that  throughout  nearly  its  entire  length 
the  stream  is  reestablished  in  the  old  course.  The  portion  below  the  mouth 
of  the  Sangamon  River  has  been  filled  to  a  level  less  than  100  feet  above 
the  present  stream.  The  portion  above  the  mouth  of  the  Sangamon  has 
e^adently  been  filled  to  irregular  heights,  as  shown  by  terraces  in  the  valley 
and  on  its  tributaries.  The  greatest  filling  seems  to  have  been  at  Peoria, 
where  the  Shelbyville  moraine  crosses.  Terraces  of  tributary  streams  here 
indicate  a  filling  of  not  less  than  170  feet  above  the  present  river  level. 
Portions  of  the  valley  above  Peoria  seem  to  have  been  filled  to  scai-cely 
100  feet  above  the  stream,  while  the  filling  below  Peoria  declines  rapidly 
to  a  level  100  feet  or  less  above  the  stream.  The  preglacial  tributaries 
leading  into  the  lower  Illinois  are  more  completely  filled  than  the  main 
valley.  As  far  down  as  the  mouth  of  the  Sangamon  it  is  impossible  to  trace 
the  courses  of  eastern  tributaries,  so  complete  has  been  the  filling,  and 
below  the  mouth  of  that  stream  the  tributary  valleys  are  traceable  for  only 
a  few  miles  in  the  lower  courses  of  the  present  streams.  The  western 
tributaries,  as  shown  below,  may  be  traced  in  several  instances  some  distance 
back  from  the  main  valley. 

The  valley  of  the  lower  Illinois  ranges  in  width  from  2^  to  fully  15 
miles.  Its  greatest  expansion  is  just  above  the  mouth  of  the  Sangamon, 
and  the  full  width  of  the  preglacial  valley  at  this  point  is  not  known.  The 
sandy  bottoms  have  a  breadth  of  12  to  15  miles,  but  the  uplands  to  the 
east  are  filled  with  drift  which  extends  far  below  the  level  of  the  river  bot- 
toms, as  shown  by  numerous  well  sections.  The  valley  is  also  broad  in  the 
vicinity  of  the  bend  of  the  Illinois.  The  sandy  and  gravelly  bottoms  have 
a  width  of  6  or  8  miles,  and  the  preglacial  valley  has  still  greater  width. 

The  narrowest  portions  of  the  lower  Illinois  Valley  are  a  short  section 
at  the  city  of  Peoria,  where  it  passes  through  the  Shelbyville  morainic 
system,  and  a  section  embracing  the  lower  60  miles,  where  it  traverses  the 
Eocarboniferous    and   Silurian  limestones.      The  reduced  width  near  the 


500  THE  ILLINOIS  GLACIAL  LOBE. 

mouth  of  the  stream  is  in  all  probability  due  to  the  hardness  of  the  foi-ma- 
tion  excavated.  It  is  not  so  certain  that  the  construction  at  Peoria  is  due 
to  the  same  cause.  Indeed,  there  is  a  possibility  that  the  stream  here  has 
been  deflected  across  a  projecting  point  of  the  west  bluff.  The  existence  of 
a  broader  channel  to  the  east,  however,  has  not  been  demonstrated. 

Several  borings  have  been  made  along  this  preglacial  valley,  and  tliey 
present  variations  in  the  altitude  of  the  rock  bottom  which  are  somewhat 
perplexing.  The  borings  in  the  vicinity  of  the  bend  of  the  Illinois  at  Peru, 
Princeton,  and  Bureau  Junction  show  a  rock  bottom  only  325  to  340  feet 
above  tide.^  Below  this  bend  the  rock  bottom  is  usually  encountered  at  a 
slightly  higher  elevation.  The  majority  of  the  Avells  are  located  within  a 
mile  of  the  bluff  of  the  preglacial  valley,  which  might  perhaps  signif}-  that 
the  deepest  part  of  the  channel  had  not  been  struck.  But  wells  at  Beards- 
town,  in  the  midst  of  the  valley,  enter  rock  at  a  level  as  high  as  at  the  bend 
of  the  Illinois,  125  miles  up  the  valley.  Bridge  foundations  near  the  mouth 
of  the  Missouri  and  at  St.  Louis,  103  and  128  miles,  respectively,  below 
Beardstown,  show  the  rock  bottom  to  descend  to  a  level  slightly  less  than 
300  feet  above  tide,  or  about  50  feet  lower  than  at  Beardstown  and  at  the 
bend  of  the  Illinois.  It  is  barely  possible  that  these  bridge  foundations 
have  not  extended  out  to  the  deepest  part  of  the  channel,  but  it  seems 
scarcely  probable  that  the  floor  has  a  much  lower  level  hi  the  middle  of  the 
channel.  The  amount  of  descent  below  Beardstown  is  not  remarkably 
low,  but  in  the  134  miles  from  Princeton  to  Beardstown  there  appears  to  be 
no  descent. 

This  suggests  the  query  whether  there  may  not  have  been  a  differen- 
tial northward  depression  in  the  portion  of  the  Illinois  Valley  north  from 
Beardstown.  To  fully  establish  this  depression,  it  will  be  necessary  to 
make  certain  that  there  is  no  deeper  portion  of  the  valley  leading  past 
Beai-dstown  and  other  points  in  the  lower  course  of  the  stream.  In  view  of 
the  possibility  of  northward  depression,  it  seems  pertinent  to  refer  to  a 
possible  cause  for  such  a  depression.     To  the  general  cause  for  northward 

I  lu  a  paper  published  iu  the  .Journal  of  Geology  (Vol.  Ill,  1895)  the  writer  ealled  attention 
to  a  horiug  at  Princeton,  Ulinois,  which  was  reported  to  have  penetrated  440  feet  of  drift  and  to  have 
entered  rock  at  210  feet  above  tide.  A  subsequent  boring,  only  a  few  feet  distant,  entered  roek  at  370 
feet,  hut  passed  through  a  soft  shale  between  370  and  440  feet.  It  is  now  thought  that  the  well  first 
made  may  also  have  entered  this  shale  at  a  depth  of  about  370  feet,  or  an  elevation  340  feet  above 
tide. 


ILLINOIS  RIVEE  DRAINAGE  BASIN. 


50X 


depression,  found  in  the  weight  of  the  ice  sheet,  an  additional  cause  is  here 
fonnd  in  the  great  amount  of  drift  deposited  along  the  course  of  the  old 
valley.  This  valley  from  the  vicinity  of  Pekin  noilhward  is  filled,  as  Avell 
as  bordered,  by  heavy  deposits  of  drift,  which  are  rarely  less  than  200  feet 
in  depth  and  which  reach  a  probable  maximum  of  between  500  and  600 
feet  in  the  district  north  of  Princeton,  where  the  moraine  occupies  the  old 
valley.  This  weight  of  drift,  unlike  that  of  the  ice  sheet,  still  continues  to 
be  an  obstacle  to  the  return  of  the  valley  floor  to  its  former  altitude,  if  not 
a  direct  cause  of  depression.  Possibly  it  even  now  is  causing  a  depression 
of  that  region,  and  the  low  gradient  of  this  portion  of  the  Illinois  may 
perhaps  be  explained  in  part  by  such  a  depression. 

In  the  following  table  the  available  data  concerning  the  altitude  of  the 
rock  floor  compared  with  the  present  Illinois  are  presented: 

Altitudes  of  rock  floor  and  present  loicer  Illinois  River. 


Distance. 


Low  -water 
(above  tide) . 


Kock  floor 
(above  tide). 


Princeton  (abandoned  channel) 

Bnreau  Junction  (Bureau  Creek  Valley) 

Hennepin 

Putnam 

Henry 

Peoria  (Brigham's  well) 

Pekin  (city  well) 

Beardstown 

Month  of  Illinois 

Bollefontaine,  Mo.  (bridge) 

East  St.  Louis,  111.  (bridge) 


Miles. 

0 

9 

4 

7 

6 

34 

11 

63 

86 

17 

25 


Feet. 


a  438 

438 

438 

429 

427.3 

418.6 

403.6 

402-i- 

380 

Feet. 
340 
340 
380 
340 
355 
341 
325 
345 
(?) 
295 
284 


a  A  dam  located  at  Henry,  Illinois,  raises  tbe  river  to  438.1  feet.    Tbe  altitudes  at  points  below  Henry  are  given 
at  tbe  natural  level  of  tbe  river. 

THE   UPPER   ILLINOIS. 

In  the  41  miles  from  the  junction  of  the  Des  Plaines  and  Kankakee 
down  to  Utica,  where  apparently  a  small  preglacial  tributary'-  of  the  Illinois 
is  entered,  the  course  of  the  present  Illinois  is  independent  of  preglacial 
drainage  lines.  About  midway  of  its  westward  course  it  crosses  the  Mar- 
seilles moraine.  This  no  doubt  for  a  considerable  period  held  a  lake  in  the 
basin  at  the  head  of  the  river  (the  Morris  Basin),  but  was  eventually  cut 
down  to  the  level  of  the  low  part  of  this  basin.     From  the  Marseilles 


502 


THE  ILLINOIS  GLACIAL  LOBE. 


moraine  westward  the  channel  found  no  prominent  drift  bamers  to  remove, 
but  has  been  compelled  to  cut  down  50  to  75  feet  into  the  rock  in  opening 
an  outlet  from  the  Morris  Basin'into  the  valley  of  the  lower  Illinois. 

In  the  41  miles  to  the  foot  of  the  rapids  near  Utica  the  stream  falls  47 
feet,  or  slightly  more  than  1  foot  to  the  mile.  This  fall  is  far  from  regular, 
there  being  a  series  of  rock  rapids  separated  by  pools.  The  following 
table  of  variations  is  based  upon  data  published  by  Cooley.^  In  the  first 
mile  a  fall  of  44  inches  is  made,  after  which  for  nearly  12  miles  the  fall 
is  less  than  4  inches  to  the  mile,  and  in  the  next  12  miles  is  but  8^  inches 
to  the  mile  (if  the  Marseilles  dam  were  removed).  This  portion  apparently 
crosses  lines  of  preglacial  valleys,  for  wells  indicate  that  the  drift  extends 
in  places  50  to  60  feet  below  the  river  level.  Near  Marseilles  a  fall  of  10 
feet  is  made  in  about  1  ^  miles,  below  which  for  over  5  miles  a  rate  of  fall  is 
continued  which  averages  about  2  feet  to  the  mile.  The  rate  then  decreases 
to  less  than  6  inches  to  the  mile.  This  is  maintained  for  6.7  miles.  Another 
rapid  is  then  passed,  with  a  fall  of  6.8  feet  in  2.6  miles,  when  a  pool  is 
reached,  near  Utica,  that  is  formed  by  the  dam  at  Henry,  20  miles  below. 
The  above  conditions  are  set  forth  in  the  following  table : 

Table  showing  variations  in  bed  of  upper  Illinois  River. 


Location. 


Mouth  of  Kaukakee  River 
One  mile  below 

Head  of  Marseilles  pool  .. 

Marseilles,  below  ilaiii 

Foot  of  Marseilles  rapids  . 

Mouth  of  Fox  Kiver 

Head  of  rapids 

Foot  of  rapids  near  Utiea. 


Distance. 

Low  water 
(above  tide). 

Fall  per 
mile. 

Miles. 

Feet. 

Incfies. 

0 

485.3 

1 

481.6 

44.04 

11.7 

477.9 

3.80 

12.7 

468.8 

8.59 

1.5 

458.3 

84.00 

5.3 

447.9 

23.54 

6.7 

444.9 

5.37 

2.6 

438.1 

31.38 

This  portion  of  the  lUinois  Valley,  although  of  post-Wisconsin  age, 
has  a  channel  more  than  a  mile  in  average  width  and  nearly  100  feet  in 
average  deptli.  Yet  at  present  it  is  the  line  of  discharge  for  an  area  of 
only  12,000  square  miles.     The  influence  of  the  waters  dischai-ged  from 


I  Lake  aud  Gulf  Waterway,  by  L.  E.  Cooley,  1890. 


ILLINOIS  RIVER  DRAINAGE  BASIN.  503 

Lake  Chicago,  and  also  from  the  ice  lobes  north  and  east  of  the  Kankakee, 
is  plainly  shown  in  the  great  size  of  this  valley,  as  has  been  pointed  ont 
on  preceding  pages. 

DBS   PLAINES    RIVER. 

The  Des  Plaines  River  drains  a  narrow  strip  extending  north  to  south 
a  distance  of  90  miles,  from  Kenosha  County,  Wisconsin,  to  the  head  of  the 
Illinois  in  eastern  Grrundy  County,  Illinois.  The  greatest  width  of  the 
watershed  is  scarcely  25  miles.  The  area,  as  above  noted,  is  1,392  square 
miles.  Aside  from  the  Des  Plaines  River  there  are  only  four  noteworthy 
ti'ibutaries — Dupage  River,  Jackson  Creek,  Hickory  Creek,  and  Salt  Creek. 

The  portion  of  the  Des  Plaines  watershed  north  from  the  Chicago  C)ut- 
let  falls  within  the  low  area  bordering  Lake  Michigan  inside  the  Valparaiso 
morainic  system.  It  still  discharges  into  the  lake  at  flood  stages  through 
a  portion  of  the  old  outlet  known  as  "Mud  Lake"  and  South  Chicago 
River.  It  is  thought  by  Cooley  and  by  others  familiar  with  the  ground, 
including  the  present  writer,  that  the  entire  discharge  may,  until  within  a 
few  hundred  years,  have  been  into  the  lake  instead  of  down  the  Chicago 
Outlet.  The  divide  between  Mud  Lake  and  Chicago  River  is  a  flat  silt- 
covered  tract  situated  near  Kedzie  avenue,  in  Chicago.  The  south  branch 
of  Chicago  River  has  a  channel  with  a  capacity  proportioned  to  such  a  stream 
as  the  Des  Plaines,  and  the  bed  of  Mud  Lake  bears  evidence  of  being  the 
line  of  discharge  from  the  Des  Plaines  to  the  Chicago  River.  Furthermore, 
the  portion  of  the  Des  Plaines  Valley  below  Summit  (where  Mud  Lake  leads 
off"  from  the  Des  Plaines)  carries  only  a  poorly  defined  channel  a  foot  or 
two  in  depth.  Cooley  remarks:  "Had  the  Des  Plaines  gone  southward 
ever  since  the  abandonment  of  the  ancient  outlet,  it  would  ere  this  have 
grooved  itself  in  the  rock,  built  up  its  banks,  and  reduced  the  prism  of  Lake 
Joliet  to  present  requirements."^  The  cause  for  the  deflection  into  the  old 
lake  outlet  is  supposed  to  be  a  silting  up  of  the  Mud  Lake  channel.  This 
matter,  however,  has  not  been  carefully  investigated  by  the  writer.  Cooley 
remarks  concerning  this  diversion: 

There  are  many  ways  in  which  the  long  flat  divide  at  Kedzie  avenue  could  have 
been  built  up,  and  we  believe  there  is  a  tradition  that  the  beaver  was  concerned  in 
the  matter.  In  any  event,  the  work  once  initiated,  natural  silting  would  carry  it  on 
until  the  waters  were  turned  out  across  the  old  pass.- 


'  See  report  of  Illinois  State  Board  of  Health,  1889,  pp.  54,  55,  69-75. 
^Op.  cit.,  p.  71. 


504  THE  ILLINOIS  GLACIAL  LOBE. 

By  this  interpretation  the  Dupage  and  other  tributaries  of  the  lower  Des 
Plaines,  as  well  as  the  jiortion  of  the  Des  Plaines  itself  outside  the  Valpa- 
raiso morainic  system,  should  be  referred  to  a  distinct  di'ainage  basin  from 
that  of  the  upper  Des  Plaines.  The  upper  Des  Plaines,  as  above  defined, 
has  an  area  of  524  square  miles  and  a  length  of  62  miles  (Cooley).  If  Salt 
Creek  be  included,  the  area  is  634  squai'e  miles.  At  the  soiu-ce  of  the  Des 
Plaines  is  a  slough  which  drains  northward  to  Root  Eiver,  a  tributary  of 
Lake  ^lichigan  entering  at  Racine,  AVisconsin,  as  well  as  southward  to  the 
Des  Plaines,  and  which  stands  112  feet  above  Lake  Michigan  (Cooley). 
The  course  of  the  upper  Des  Plaines  is  governed  by  till  ridges  on  its  east 
border,  as  indicated  above,  except  for  a  few  miles  near  its  entrance  into  the 
Chicago  Outlet.     It  there  traverses  a  southward-sloping  jjlain. 

The  course  of  Salt  Creek  also  is  governed  by  a  till  ridge  on  its  east 
border  as  far  south  as  Fullersburg.  It  there  turns  east  tlnough  a  gap  in 
the  ridge,  but  its  old  coui'se  was  southward  past  Western  Springs,  tlu-ough 
Flag  Creek  Valley,  to  the  Chicago  Outlet  near  Willow  Springs.  Its  old 
valley  is  larger  than  the  new  one,  from  which  it  is  inferred  that  the  deflec- 
tion is  somewhat  recent.  The  cause  for  the  deflection  is  perhaps  a  silting 
up  at  the  mouth  which  followed  the  abandonment  of  the  lake  outlet.  Con- 
ditions for  such  silting  are  favorable,  for  there  is  scarcely  any  fall  along  rhe 
bed  of  the  outlet  for  several  miles  below  the  old  mouth  of  the  creek.  This 
interpretation,  however,  is  one  which  has  not  been  fullv  tested  bv  observa- 
tions in  the  field. 

For  30  miles  below  the  point  where  the  Des  Plaines  enters  the  Chicago 
Outlet  it  traverses  the  Valparaiso  morainic  system  and  receives  no  tributaries 
of  importance,  for  much  of  the  drainage  there  is  only  the  bluff  drainage. 
It  has  not  in  this  interval  perceptibly  modified  the  bed  of  the  old  lake  out- 
let. There  is  the  "12-mile  level"  below  Summit,  soon  followed  bv  the 
descent  of  about  70  feet  in  8  miles.  Farther  down  are  two  pools — one  below 
Joliet,  known  as  Lake  Joliet,  another  near  the  mouth  of  Dupage  River, 
known  as  Lake  Dupage — which  are  separated  by  an  interval  of  3  miles  of 
slope  with  a  fall  of  about  13  feet.  There  is  also  a  fall  of  about  2i  feet  iu 
the  lialf  mile  from  Lake  Dupage  to  the  junction  with  the  Kankakee  at  the 
head  of  tlie  Illinois.  The  only  true  flood-plain  bottoms  are  in  the  7  miles 
between  Lake  Joliet  and  the  head  of  tlie  Illinois.  These  lie  witliin  the 
range  of  backwater  from  the  Kankakee  and  are  o^■el•flowed  only  in  case  of 


ILLINOIS  EIVEK  DEAINAGE  BASIN.  505 

floods  from  that  stream  (Cooley).  These  flood  plains  have  been  built  up 
by  overflow  to  about  the  average  hig'h-water  level. 

At  Joliet  an  eastern  tributary — Hickory  Creek — having-  a  watershed  of 
130  square  miles,  enters  the  valley  and  forms  a  limited  area  of  flood  plain 
in  its  delta.  Its  source  is  in  the  midst  of  the  Valparaiso  moraine.  Another 
eastern  tributary^Jackson  Creek — having  a  watershed  of  about  86  square 
miles,  enters  nearly  opposite  the  mouth  of  the  Dupage  and  helps  to  swell 
the  lower  Des  Plaines.  This  stream  heads  in  the  main  belt  of  the  Valpa- 
raiso system  and  passes  through  the  outer  ridge  of  that  system  just  north  of 
Elwood. 

The  Dupage  River,  which  enters  only  4  miles  above  the  junction  of 
the  Des  Plaines  with  the  Kankakee,  has  a  watershed  of  about  366  squai'e 
miles.  It  drains  the  plain  lyiug  between  the  Minooka  till  ridge  and  the 
Valparaiso  morainic  system.  Its  east  branch  for. a  few  miles  flows  south- 
ward between  the  outer  ridge  and  the  main  moraine  of  the  Valparaiso 
system,  but  passes  westward  through  a  g-ap  in  this  ridge  before  uniting  with 
the  west  branch. 

The  old  lake  outlet  down  the  Des  Plaines,  the  channels  connecting 
the  Des  Plaines  with  the  lower  Dupage,  and  the  gravel  terraces  on  each 
stream,  have  received  attention  on  preceding-  pages. 

KANKAKEE   RIVER. 

The  Kankakee  River,  which  unites  with  the  Des  Plaines  to  form  the 
Illinois,  drains  an  estimated  area  of  5,146  square  miles,  of  which  3,040 
square  miles  lie  in  Indiana  and  the  remainder  in  Illinois.  The  general 
trend  of  its  watershed  is  east  to  west,  and  the  extreme  length  is  about  "200 
miles.     The  greatest  width  from  north  to  southis  about  70  miles. 

The  watershed  has  its  northern  limits  in  the  Valparaiso  morainic  system, 
and  all  the  important  northern  tributaries  find  their  sources  in  this  morainic 
system.  Its  southern  limits  in  the  portion  below  the  mouth  of  the  Iroquois 
are  found  in  the  Marseilles  moraine.  The  Iroquois  is  a  somewhat  distinct 
watershed,  draining  basins  south  of  the  Iroquois  and  Marseilles  moraines 
and  passing  through  a  gap  in  the  Marseilles  moraine  to  enter  the  Kankakee. 
There  is  no  well-defined  ridge  separating  its  watershed  from  the  Wabash 
watershed.  The  eastern  limits  of  the  Kankakee  watershed  are  inainly  in 
the  Maxinkuckee  moraine  of  the  Saginaw  lobe,  but  Yellow  River  drains  a 


506  THE  ILLINOIS  GLACIAL  LOBE. 

small  tract  lying  east  of  the  moraine.  As  above  noted,  the  Kankakee 
formerly  constituted  the  line  of  discharge  for  the  8t.  Joseph  River,  now 
tributary  to  Lake  Michigan,  and  it  is  probable  that  it  carried  also  a  large 
amount  of  glacial  drainage  from  the  Saginaw  and  Lake  Michigan  lobes  (see 
PI.  XV). 

With  the  exception  of  the  somewhat  distinct  watersheds  of  the  L-oquois 
and  Yellow  rivers,  the  Kankakee  area  constitutes  a  single  great  basin, 
having  only  small  tributaries  leading  directly  from  the  rim  to  the  river  or 
marsh.  The  Kankakee  marsh  embraces  probably  1,00U  square  miles,  or 
about  one-fifth  of  the  watershed.  In  addition  to  this,  about  3,000  square 
miles  have  very  poor  drainage.  The  best-drained  portions  are  on  the 
Valparaiso  moraine  and  the  plains  in  Illinois  between  the  Valparaiso  and 
Marseilles  moraines.  These,  however,  are  poorly  supplied  with  channels 
for  discharge,  and  much  ditching-  and  tile  draining  have  been  found  necessary. 
The  head  of  the  Kankakee  marsh  near  South  Bend,  Indiana,  stands  about 
140  feet  above  Lake  Michigan,  or  720  feet  above  tide.  From  this  jJoint  to 
Momence,  Illinois,  a  distance  of  82  miles  by  direct  line,  there  is  a  continuous 
marsh  which  has  a  somewhat  uniform  descent  of  about  15  inches  to  the 
mile,  its  altitude  at  Momence  being  104  feet  lower  than  at  South  Bend. 
The  windings  of  the  stream  are  reported  by  Cooley  to  increase  its  length 
to  about  250  miles,  and  thus  to  reduce  the  fall  to  onlj^  5  inches  to  the  mile. 
Tlie  amount  of  water  above  the  junction  with  Yellow  River  is  insufficient  to 
form  a  well-defined  channel,  but  below  that  point  there  is  quite  a  definite 
open  channel.  The  small  tributaries  are  usually  lost  in  the  marsh  before 
reaching  the  main  stream.  The  Kankakee  Valley  Drainage  Company  has 
estimated  that  625  square  miles  may  be  directly  reclaimed  and  1,000 
square  miles  benefited  by  systematic  ditching.^ 

At  Momence  occurs  the  fii'st  limestone  outcrop  in  the  bed  of  the  river. 
In  the  14  miles  below  Momence  to  the  junction  with  the  Iroquois  there  is  a 
rock  bed  and  a  fall  of  25  feet.  In  the  33i  miles  from  the  mouth  of  the 
Iro([Uois  to  the  head  of  the  Illinois  the  Kankakee  falls  103  feet,  or  an 
average  of  3  feet  to  the  mile.  There  are  rapids  near  Altorf  and  at  AVil- 
mington,  each  of  which  have  a  descent  of  about  20  feet.  The  inner  valley 
is  l)ut  little  wider  than  the  stream,  and  has  a  depth  of  ouly  15  feet  at 
Momence,  25  feet  at  Kankakee,  and  aboat  35  feet  in  western  Kankakee  and 


'  See  official  rc]Mirt  to  governor  of  Indiana,  1882. 


ILLINOIS  EIVER  DRAINAGE  BASIN.  507 

southern  Will  counties,  though  at  a  few  points  it  approaches  50  feet.  Out- 
side of  this,  as  previously  described,  there  is  a  broad  bottom,  averaging- 
about  2  miles  in  width,  which  has  a  low  bluff  of  till  along  the  north  border, 
rising-  15  to  25  feet  or  more  above  it.  But  on  the  south  there  are  sandy 
ridges  and  knolls  which  seldom  present  a  definite  bluff  line.^ 

Yellow  River  has  a  drainage  area  of  about  700  square  miles,  of  which 
probably  500  square  miles  are  within  the  liTiits  of  the  Maxinkuckee 
moraine  of  the  Saginaw  lobe  and  outside  the  region  under  discussion. 
This  portion  on  the  Saginaw  drift  is  widely  branching  and  drains  the 
greater  part  of  Marshall  County,  together  with  small  parts  of  St.  Joseph," 
Elkhart,  and  Kosciusko  counties.  The  portion  west  of  the  Maxinkuckee 
moraine  consists  mainly  of  its  immediate  channel  and  the  outlet  of  Twin 
Lakes,  its  course  being  through  a  sand-covered  district  in  which  the 
di'ainage  is  very  imperfect.  None  of  this  watershed  can  be  considered 
well  drained,  although  the  headwater  portion  resembles  the  neighboring 
portions  of  northern  Indiana,  which,  like  it,  are  under  cultivation.  The 
soil,  being  a  sandy  loam,  requires  less  perfect  surface  drainage  than  clay 
soils,  such  as  characterize  the  drift  of  the  Illinois  lobe. 

The  Iroquois  River  has  a  watershed  of  about  2,000  square  miles, 
though  much  of  this  watershed  is  very  imperfectly  drained  by  it.  Fully 
800  square  miles,  or  nearly  one-half,  lies  in  Indiana.  At  Watseka  the 
river  receives  its  principal  tributary — Sugar  Creek.  Below  Watseka  are 
three  noteworthy  tributaries — Spring  Creek,  Langum  Creek,  and  Beaver 
Creek.  In  its  passage  through  the  Marseilles  moraine  in  the  lower  5  miles 
of  its  course  considerable  descent  is  made,  but  elsewhere  the  stream  is  gen- 
erally sluggish,  and  so  are  the  tributaries. 

The  west-flowing  portion  of  the  Iroquois  drains  a  large  sandy  area,  in 
Indiana  south  of  the  Iroquois  moraine.  It  passes  thi'ough  that  moraine 
before  reaching  Watseka.  Sugar  Creek  drains  the  outer  face  of  the 
Iroquois  moraine  in  the  jjortion  southeast  from  Watseka,  while  Beaver 
Creek  furnishes  the  chief  drainage  for  the  outer  face  northwest  from 
Watseka.     The  basin  in  Iroquois  County,  south  of  the  Marseilles  moraine, 

'  Many  dat,a  concerning  the  Kankakee  Basin  have  been  collected  by  Prof.  L.  E.  Cooley  and  pre- 
sented iu  a  piiper  contained  in  tlie  lleport  ol'  the  Illinois  State  Board  of  Health,  1889.  The  writer  is 
indebted  to  this  report  for  many  of  the  statistics  above  presented,  as  well  as  for  those  of  the  Iroquois 
and  Yellow  rivers,  presented  below. 


508  THE  ILLINOIS  GLACIAL  LOBE. 

has  rather  imperfect  drainage  through  the  several  tributaries  of  the  Iroquois. 
The  streams  are  separated  by  poorly  drained  plains  several  miles  in  width, 
in  which,  by  systematic  ditching,  the  productiveness  of  the  soil  has  been 
greatlv  increased. 

AV   SABLE  CKEEK  AND  NETTLE  CREEK. 

An  Sable  Creek  (spelled  also  Aux  Sable)  has  a  drainage  area  of  about 
218  square  miles,  and  enters  the  Illinois  4.7  miles  below  the  junction  of  the 
Des  Plaines  and  Kankakee  rivers.  It  drains  much  of  the  northern  portion 
of  the  Morris  Basin  lying  between  the  Minooka  till  ridge  and  the  portion 
of  the  Marseilles  moraine  north  of  the  Illinois  River.  It  has  widely  branch- 
ing- headwaters  which  find  their  source  in  the  Marseilles  moraine.  The 
lower  course  follows  the  outer  or  west  border  of  the  Minooka  Ridge  south- 
ward to  the  Illinois,  and  the  east  side  of  the  watershed  is  very  narrow.  A 
portion  of  this  basin  is  included  in  the  Morris  topographic  sheet. 

Nettle  Creek,  another  stream  di'aining  the  east  slope  of  the  Marseilles 
moraine,  enters  the  Illinois  from  the  north  at  Morris,  about  5  miles  below 
the  mouth  of  An  Sable  Creek.  It  also  has  widely  branching  headwaters 
leading-  southeastward  from  the  Marseilles  moraine.  The  drainag-e  area  is 
estimated  by  Cooley  to  be  only  63  square  miles. 

MAZON  CREEK,  WAUPECAN  CREEK,  ETC. 

Mazon  Creek,  with  an  estimated  drainage  area  of  540  square  miles, 
enters  the  Illinois  at  Morris,  about  10  miles  west  from  the  head  of  the  river. 
Like  Au  Sable  Creek,  it  has  a  widely  branching  headwater  drainage  whose 
source  is  in  the  Marseilles  moraine.  The  lower  course  leads  northwestAvard, 
draining  at  right  angles  to  that  of  the  several  tributaries.  There  is  a  sandy 
plain  extending-  from  the  main  creek  eastward  to  the  Kankakee,  on  which 
there  is  no  perceptible  dividing  ridge.  The  headwater  tributaries  descend 
rapidly,  but  the  main  stream  is  rather  sluggish.  Wide  intervals  between 
the  tributaries  are  imperfectly  drained,  but  by  sj^stematie  ditching  the  land 
has  been  rendered  very  productive. 

Waupecan  Creek  and  Hog  Run  are  two  small  southern  tributaries  of 
the  Illinois  entering  Ijelow  the  mouth  of  Mazon  Creek  and  draining  the 
portion  of  the  east  slope  of  the  Marseilles  moraine  lying  between  tlie  Illi- 
nois River  ;iiid  the  Mazon  watershed.     Their  combined  area  is  onh-  about 


w  s 


ILLINOIS  EIVER  DEAINAGE  BASIN.  509 

70  square  miles.     Like  the  headwaters  of  Mazoii  Creek,  they  flow  north- 
eastward down  the  slope  from  the  moraine  to  the  plain. 

It  will  be  observed  that  Mazon  Creek  and  these  streams  drain  the  south 
part  of  the  Mon-is  Basin.  A  portion  of  this  area,  appears  on  the  Morris 
topographic  sheet. 

FOX   RIVER. 

For  about  20  miles  in  the  vicinity  of  the  Marseilles  moraine  the  Illinois 
receives  no  tributary  worthy  of  mention,  as  may  be  seen  by  reference  to 
the  Marseilles  topographic  sheet.  But  just  west  of  the  Marseilles  moraine, 
at  a  distance  of  33  miles  from  the  head  of  the  Illinois,  Fox  River  is  received. 
Its  drainage  area  is  about  2,500  square  miles,  or  more  than  one-third  as 
great  as  the  portion  of  the  watershed  of  the  present  Illinois  above  the 
mouth  of  this  tributary.  It  lies  mainly  in  Illinois,  but  the  source  of  the 
stream  is  in  southern  Wisconsin. 

For  a  distance  of  nearly  75  miles  from  its  source  Fox  River  drains 
only  a  narrow  strip  among  the  morainic  ridges  of  the  composite  belt  pre- 
viously described.  In  this  portion  of  its  course  its  fall  amounts  to  but  a 
few  inches  to  the  mile,  and  it  expands  at  frequent  intervals  into  lakes  and 
marshes,  between  which  are  short  spaces  liaAang  a  narrow  and  well-defined 
channel.  Near  the  point  of  divergence  of  the  Marseilles  moraine  from  the 
Bloomington  morainic  system  above  Elgin,  Illinois,  the  river  begins  a  rapid 
descent  to  the  low  plain  that  lies  on  the  outer  border  of  the  Marseilles 
moraine,  and  follows  this  plain  to  its  mouth. 

The  stream  has  no  valley  until  it  begins  the  descent  to  this  plain.  It 
there  for  a  few  miles  has  cut  to  a  depth  of  nearly  100  feet,  but  in  the 
passage  through  the  plain  its  bed  is  sunk  to  a  depth  of  only  40  or  50  feet, 
except  for  a  few  miles  near  its  mouth,  where  it  cuts  deeper  to  enter  the 
Illinois.  The  valley  is  also  narrow  throughout  its  entire  length,  and  pre- 
sents a  consjjicuous  contrast  to  the  broad  valley  of  the  ujDper  Illinois.  Its 
channel  even  in  the  lower  75  miles  has  a  breadth  of  only  about  one-eighth 
mile  and  a  depth  scarcely  half  as  great  as  that  of  the  neighboring  portion 
of  the  Illinois,  yet  it  is  better  favored  than  the  Illinois  for  the  development 
of  a  drainage  line,  there  being  no  morainic  ridge  to  cross  and  a  proportion- 
ately small  amount  of  rock  to  excavate.  Instead  of  an  excavation  one-third 
as  great  as  that  of  the  upper  Illinois,  this  stream  has  accomplished  scarcely 
one-sixteenth  as  much  work.     These  contrasts  are  well  shown  in  the  Ottawa 


510  THE  ILLINOIS  GLACIAL  LOBE. 

topographic  sheet  of  this  Survey,  a  portion  of  whicli  is  here  reproduced 
(see  PI.  XIX). 

The  principal  tributaries  of  Fox  Ri^^er  all  lie  on  the  west  side,  there 
being  but  a  narrow  strip  of  watershed  on  the  east  side  of  the  river.  Among 
the  tributaries  may  be  mentioned  Nippersink  Creek,  which  enters  about  6 
miles  south  of  the  State  line;  Blackberry  Creek,  which  enters  opposite 
Yorkville;  Big  and  Little  Rock  creeks,  which  unite  just  before  entering  the 
river,  5  miles  below  Yorkville;  Somonauk  Creek,  whicli  enters  opposite 
Sheridan,  12  miles  farther  down  the  river,  and  Big  and  Little  Indian 
creeks,  which  unite  near  their  mouths  and  enter  the  river  about  10  miles 
above  its  junction  with  the  Illinois.  Nippersink  Creek  heads  in  the  com- 
posite morainic  belt  in  northern  McHenry  County  and  takes  a  zigzag  course 
among  its  ridges  through  a  series  of  marshes  for  a  distance  of  nearly  20 
miles  before  entering  the  river.  Blackberry  Creek,  as  previously  indicated, 
occupies  an  esker  trough  in  its  middle  course,  whose  size  is  many  times 
greater  than  that  of  the  remainder  of  the  creek  channel.  Before  entering 
the  esker  trough  the  creek  winds  about  among  morainic  knolls  near  the 
south  end  of  the  composite  belt.  In  its  lower  course  the  creek  does  not 
pass  directly  into  Fox  River,  but  follows  down  the  valley  about  8  miles, 
draining  a  portion  of  the  gravel  plain  which  borders  the  river.  The  remain- 
ing tributaries  above  mentioned  all  head  in  the  Bloomington  morainic 
system  or  on  the  slope  of  its  inner  ridge,  and  take  a  somewhat  direct  south- 
eastward course  to  Fox  River  Valley,  following  the  slope  of  the  plain. 
Thev  have  narrow  valleys- and  have  sunk  their  beds  but  a  few  feet  below 
the  level  of  the  plain,  except  near  their  mouths,  where  they  have  cut  down 
to  a  level  corresponding  to  that  of  Fox  River.  Some  portions  of  the  plain 
west  of  Fox  River  are  naturally  very  imperfectly  drained,  but  by  ditching 
and  tile  di-aining  they  have  been  brought  to  a  high  degree  of  fertility. 
The  slope  of  the  plain  averages  usually  several  feet  to  the  mile;  conse- 
quently drainage  is  easily  developed. 


COVEL   GREEK. 


This  small  southern  tributary  of  the  Illinois  drains  an  area  of  about  100 

square  miles  lying  between  the  Marseilles  moraine  and  Farm  Ridge,  tlie 

'inner  ridg-e  of  the  Bloomington  morainic  system.     It  enters  the  llHnois 


ILLINOIS  RIVEE  DEAINAGB  BASIN.  511 

about  3  miles  below  the  mouth  of  Fox  River.  .  The  basin  drained  by  this 
stream,  as  previously  described,  carries  sand  ridges,  which  were  perhaps 
formed  by  a  lake-like  expansion  of  the  river  prior  to  the  opening  of  the 
channel  to  the  west. 

VERMILION    RIVER. 

This  southern  tributary  of  the  Illinois  should  not  be  confused  with  a 
stream  of  the  same  name  which  leads  into  Wabash  River  from  eastern 
Illinois.  To  distinguish  these  streams,  the  names  Wabash- Vermilion  and 
Illinois- Vermilion  have  come  into  use.  Both  streams  have  their  sources  in 
the  Bloomington  morainic  system  at  the  reentrant  angle  in  southeastern 
Livingston  and  western  Ford  counties.  ■  The  course  of  the  Illinois- Vermilion 
is  northwestward,  while  that  of  the  Wabash- Vermilion  is  southeastward, 
from  the  elevated  district  in  which  they  have  their  common  source. 

The  Illinois- Vermilion  has  a  drainage  area  of  1,300  square  miles,  and 
drains  the  district  immediately  south  and  west  of  the  Marseilles  moraine  in 
Ford,  Livingston,  and  southern  Lasalle  counties.  The  main  stream  follows 
the  west  or  outer  border  of  the  inner  ridge  of  the  Bloomington  system  from 
source  to  mouth,  but  an  east  fork  leads  through  this  moraine.  The  other 
eastern  tributaries  find  their  sources  in  these  morainic  belts.  A  southern 
tributary — Rooks  Creek — heads  near  Lexington  in  Cropsey  Ridge,  another 
weak  moraine  of  the  Bloomington  system.  The  western  tributaries  drain  a 
plain  which  slopes  gradually  eastward  nearly  to  the  border  of  the  moraine. 
The  western  side  of  the  watershed  is  much  more  extensive  than  the  eastern, 
yet  no  streams  worthy  of  note  lead  across  it  to  the  Vermilion.  Its  drain- 
age is  through  small  streams  which  pass  directly  down  the  slope  to  the 
river  in  somewhat  parallel  courses. 

The  unfavorable  conditions  for  drainage  along  the  Vermilion  have  been 
discussed  on  preceding  pages.  The  plain  through  which  it  passes,  as  there 
noted,  has  little  descent  in  the  lower  40  miles  of  the  river,  and  was  appar- 
ently occupied  by  a  marsh,  if  not  by  a  shallow  lake,  until  a  stream  had 
been  given  time  to  open  a  channel  from  the  Illinois  back  several  miles  into 
the  plain.  Sandy  deposits  on  the  south  border  of  the  plain  are  thought  to 
be  due  to  the  existence  of  a  lake  in  the  portion  to  the  north.  The  narrow- 
ness of  the  channel  of  the  Vermilion  River  near  its  mouth  is  well  shown  on 
the  Lasalle  topographic  sheet. 


512  THE  ILLINOIS  GLACIAL  LOBE. 

LITTLE   VERMILION   RIVEK,   ETC. 

Little  Vermilion  River  enters  the  Illinois  directly  opposite  the  mouth 
of  the  Vermilion  River,  and  sustains  a  similar  relation  to  the  inner  ridge  of 
the  Blooming'ton  morainic  system,  that  ridge  being  immediately  east  of 
each  stream.  Its  watershed,  how^ever,  comprises  only  150  square  miles. 
The  size  and  slope  of  its  valley  and  the  slope  of  bordering  uplands,  as  well 
as  the  relation  to  the  morainic  ridge  east  of  it,  are  well  displayed  on  the 
Lasalle  topographic  sheet.  The  same  sheet  also  brings  out  clearly  the 
features  of  a  neighboring  small  tributary  of  the  Illinois — Spring  Creek — 
which  enters  the  river  at  Spring  Valley.  The  features  of  another  small 
northern  tributary — Negro  Creek — are  brought  out  on  the  Lasalle  and 
Hennepin  topographic  sheets. 

The  same  sheets  also  bring  out  the  features  of  All  Forks  Creek,  a  small 
southern  tributary  of  the  Illinois,  entering  the  river  about  5  miles  above 
Hennepin.  All  Forks  Creek,  it  will  be  observed,  occupies  a  shallow 
depression  leading  westward  parallel  with  the  Illinois  River.  This  depres- 
sion was  perhaps  utilized,  if  not  produced,  in  the  early  stages  of  drainage 
development  by  a  portion  of  the  Illinois  River.  It  will  be  observed  that 
a  similar  shallow  depression  also  leads  westward  on  the  north  side  of  the 
Illinois,  passing  just  north  of  the  cities  of  Peru  and  Spring  Valley,  which 
may  also  have  been  formed  by  the  river  in  the  early  stages  of  its  develop- 
ment. A  more  careful  investigation  of  this  portion  of  the  Illinois,  where 
the  postglacial  stream  enters  the  preglacial  valle}^,  is  necessary  to  bring  out 
fully  the  history  of  the  development  of  the  present  lines  of  drainage. 

BUREAU    CREEK. 

Bureau  Creek,  which  enters  the  Illinois  from  the  northwest  at  the  great 
bend  of  the  river,  has  a  drainage  area  of  about  480  square  miles.  This 
watershed,  as  previously  shown,  is  included  mainly  between  the  two  promi- 
nent members  of  the  Bloomington  morainic  system  which  are  developed  in 
the  district  north  from  the  bend  of  the  Illinois.  In  addition  to  the  main 
creek  there  are  several  nearly  parallel  tributary  streams,  all  flowing  south- 
westward  across  the  northeastern  and  eastern  portions  of  Bureau  County. 
The  main  stream  swings  around  to  the  south  and  east,  gathering  in  the 


ILLINOIS  EIVEE  DRAINAGE  BASIN.  5  1  3 

several  parallel  tributaries  in  this  curving  portion  of  its  course.  Its  deflec- 
tion from  a  soutliwestward  course  is  caused  b}^  the  change  in  the  course 
of  the  moraine  which  lies  on  its  northern  and  western  border.  This  moraine 
furnishes  only  small  northern  and  western  tributaries  to  the  main  stream. 

The  watershed,  with  the  exception  of  the  great  moraine  on  the  north 
and  west  borders,  shows  a  perceptible  soutliwestward  descent,  amounting 
generally  to  several  feet  to  the  mile.  In  the  headwater  portions  the  main 
creek  and  also  its  tributaries  have  formed  only  shallow  ditches,  but  in  the 
lower  course  they  have  trenched  deeply  into  the  drift  dejDosits,  as  may  be 
seen  by  reference  to  the  Hennepin  topographic  sheet. 

Between  the  mouth  of  Bureau  Creek  and  the  city  of  Peoria,  a  distance 
of  about  50  miles,  the  Illinois  River  receives  no  important  tributaries.  The 
largest  is  East  Crow  Creek,  which  has  a  drainage  area  of  226  square  miles. 
Sandy  Creek,  another  eastern  tributary,  di-ains  147  square  miles;  and 
Senachwine  Creek,  a  western  tributary,  di'ains  132  square  miles.  No  others 
have  an  area  exceeding  100  square  miles.  The  smallness  of  the  western 
tributaries  is  due  to  the  close  approach  of  the  bulky  Bloomington  morainic 
system  to  the  west  bluff  of  the  Illinois.  In  most  cases  these  tributaries 
lead  somewhat  directly  from  the  moi;aine  down  to  the  valley,  but  Senach- 
wine Creek  has  been  deflected  by  a  drift  ridge  into  a  course  parallel  with 
the  moraine,  and  thus  di-ains  a  larger  area  than  the  neighboring  tributaries. 
The  eastern  tributaries  lead  directly  westwai'd  across  a  slig'htly  undulatory 
plain,  which  apparently  ofi"ered  conditions  rather  unfavorable  for  stream 
development,  there  being  very  little  descent.  The  streams,  however,  have 
overcome  this  impediment  by  trenching  deeply  near  theii'  mouths,  and  have 
thus  opened  a  fair  di-ainage  in  that  region.  The  features  are  well  shown  in 
the  Hennepin,  Lacon,  and  Metamora  sheets. 

KICKAPOO    CREEK. 

Kickapoo  Creek,  which  enters  the  Illinois  from  the  west  at  the  city  of 
Peoria,  has  a  drainage  area  of  310  square  miles,  mainly  situated  on  the 
Illinoian  drift  outside  the  limits  of  the  Shelbyville  moraine.  The  headwater 
portion,  however,  drains  a  narrow  strip  between  the  Shelbyville  and  Bloom- 
ington morainic  systems,  passing  through  the  Shelbyville  moraine  just  below 
the  village  of  Dunlap.  The  relation  of  this  stream  to  the  morainic  ridges, 
MON  xxxviii 33 


514  THE  ILLINOIS  GLACIAL  LOBE. 

and  also  the  general  features  of  its  several  tributaries  in  the  headwater  por- 
tion, may  be  seen  by  reference  to  the  Dunlap  topographic  sheet.-^ 

FARM   CREEK. 

This  small  eastern  tributary  of  the  Illinois  which  enters  directly  oppo- 
site the  city  of  Peoria  has  its  source  in  the  Bloomington  morainic  system. 
As  previously  noted,  it  carries  a  moraine-headed  terrace  which  opens  into 
the  Illinois  Valley  at  a  level  about  170  feet  above  the  stream,  thus  showing 
that  at  the  Bloomington  substage  of  glaciation  the  valley  was  filled  to  this 
unusually  high  level  in  that  vicinity.  The  stream  has  now  opened  a  valley 
down  to  the  level  of  the  50-foot  terrace  which  borders  the  Illinois,  that 
offers  a  convenient  line  for  approach  to  Peoria  from  the  east,  which  is 
utilized  by  several  railway  lines. 

MACKINAW   RIVER. 

This  important  tributary  of  the  Illinois  has  a  drainage  area  of  about 
1,200  square  miles,  which  may  conveniently  be  divided  into  three  sections: 
(1)  The  headwater  portion,  lying  inside  the  main  ridges  of  the  Bloomington 
morainic  system;  (2)  the  middle  portion,  comprising  the  section  crossing 
the  Bloomington  and  Shelbyville  morainic  systems  and  the  narrow  plain 
separating  them;  (3)  the  lower  portion,  embracing  the  meanders  of  the 
river  througt  the  Illinois  River  bottoms. 

The  upper  portion  drains  a  somewhat  elevated  till  plain  in  north-central 
McLean  and  eastern  Woodford  counties,  lying  between  the  inner  large 
moraine  and  Cropsey  Ridge,  a  minor  moraine  of  the  Bloomington  system. 
The  length  of  this  portion  of  the  river  is  about  40  miles,  and  in  much  of  its 
course  it  flows  near  the  south  border  of  the  minor  moraine.  Several  tribu- 
taries heading  in  the  large  moraine  lead  northward  to  the  river  across  a 
sloping  plain.  Another  tributary — Panther  Creek — which  drains  several 
townships  in  eastern  Woodford  County,  leads  southwestward  to  join  the 
river  at  the  point  where  it  enters  the  middle  course.  The  streams  in  this 
upper  portion  have  generally  very  shallow  channels,  seldom  more  than  25 

1 1  am  informed  that  by  mistake  !iu  uiicorreet«d  photograph  copy  of  the  Dunlap  sheet  was  sent 
to  the  engraver,  instead  of  a  corrected  copy.  The  error  involves  chiefly  an  omission  of  a  50-foot 
contour  on  the  uplands  west  of  the  Illinois.  This  should  be  borne  in  mind  in  the  examination  of  the 
Dunlap  sheet. 


ILLINOIS  EIVBR  DRAINAGE  BASIN.  515 

or  30  feet  in  depth,  and  also  very  narrow  flood  plains.  The  main  stream, 
however,  begins  to  deepen  its  channel  before  entering  the  large  moraine, 
and  has  a  depth  of  60  to  75  feet  at  the  inner  border  of  the  moraine. 

In  the  middle  course  Mackinaw  River  has  cut  a  chamiel  across  both 
the  large  moraines  of  the  Bloomington  system  and  also  the  Shelbyville 
moraine,  with  an  average  depth  of  nearly  100  feet.  The  width  of  the 
valley  increases  from  about  one-fourth  mile  in  the  inner  part  of  the  Bloom- 
ington belt  to  about  a  half  mile  at  the  outer  part  and  to  nearly  a  mile  in 
its  passage  across  the  Shelbyville  moraine.  As  previously  indicated,  its 
fall  is  very  rapid,  being  usually  several  feet  to  the  mile.  The  river  receives 
but  few  tributaries  in  this  middle  course,  and  these  drain  onl}^  small  areas. 
The  largest  tributary  is  Walnut  Creek,  which  enters  from  the  north  between 
the  two  main  ridges  of  the  Bloomington  system,  and  which  drains  probably 
100  square  miles.  Another  north  tributary — Deer  Creek — drains  a  portion 
of  the  plain  between  the  outer  Bloomington  moraine  and  the  Shelbyville 
moraine.  Little  Mackinaw  Creek,  a  southern  tributary,  drains  a  portion  of 
this  plain  south  of  the  river. 

In  its  lower  course  the  Mackinaw  River  winds  about  in  a  shallow 
channel  across  the  Illinois  Valley  for  a  distance  of  about  20  miles  and 
makes  a  descent  of  about  75  feet. 

QUIVER    CREEK. 

This  eastern  tributar}^  of  the  Illinois  has  its  entire  course  within  the 
limits  of  the  valley  of  the  Illinois  River.  It  is  the  only  stream  of  conse- 
quence found  in  an  area  comprising  not  less  than  200  square  miles  of 
sandy  bottom.  It  is  immediately  bordered  by  a  belt  of  mucky  alluvium, 
averaging  perhaps  2  miles  in  width,  whose  surface  stands  20  feet  or  more 
below  the  level  of  the  bordering  sandy  bottom.  This  appears  to  have  been 
the  former  course  of  Mackinaw  River,  and  was  perhaps  occupied  also  by  a 
portion  of  the  Illinois  River.  By  systematic  ditching  much  of  the  bordering 
districts  have  been  drained  into  this  channel.  There  are  other  bayous  in 
this  sandy  bottom  which  are  connected  with  the  Sangamon  River  through 
Crane  Creek.  These  also  were  probably  once  occupied  by  the  Mackinaw 
River,  together  with  a  portion  of  the  Illinois. 


516  THE  ILLINOIS  GLACIAL  LOBE. 


COPPERAS    CKKEK. 


This  small  western  tributary  of  the  Illinois  drains  an  area  of  about 
150  square  miles  in  southwestern  Peoria  County.  Several  of  the  tribu- 
taries, as  well  as  the  creek  itself,  have  their  courses  largely  determined  by 
preglacial  drainage  lines  which  are  only  partially  filled  by  glacial  deposits. 
There  are  other  small  western  tributaries  of  the  Illinois  between  Copperas 
Creek  and  the  mouth  of  Spoon  River,  which  also  have  their  courses  largely 
determined  by  preglacial  drainage  lines. 


SPOON   RIVER. 


This  large  western  tributary  of  the  Illinois  has  an  estimated  drainage 
area  of  1,870  square  miles.  It  enters  the  river  opposite  the  city  of  Havana. 
The  sources  of  the  stream  are  in  southwestern  Bureau  County,  a  few  miles 
west  of  the  great  bend  of  the  Illinois,  and  the  course  of  the  stream  for 
nearly  100  miles  is  west  of  south,  nearly  parallel  with  that  of  the  Illinois 
River.  It  then  turns  abruptly  southeastward,  and  in  a  distance  of  about  25 
miles  joins  the  Illinois. 

In  its  headwater  portion  Spoon  River  receives  the  drainage  of  the 
western  slope  of  a  portion  of  the  Bloomington  and  Shelbyville  morainic 
systems.  With  this  exception  the  entire  watershed  lies  outside  the  limits  of 
the  Wisconsin  drift,  occupying  a  region  covered  by  Illinoian  drift,  upon 
which  there  is  a  capping  of  loess. 

The  course  of  the  main  stream,  and  also  of  several  tributaries,  appears 
to  have  been  determined  largely  by  preglacial  drainage  lines  wliich  have 
been  but  partially  filled  by  the  glacial  deposits.  The  filling,  however,  has 
been  so  great  that  the  present  streams  conform  only  in  a  general  way  to 
the  course  of  the  preglacial  lines,  and  thus  at  a  few  places  they  trench  upon 
the  projecting  rock  points  in  the  bluffs  of  the  preglacial  valleys,  and  give 
the  appearance  of  being  in  courses  independent  of  preglacial  lines. 

The  river  receives  several  tributaries,  both  on  the  east  and  on  the  west, 
which  have  a  length  each  of  15  to  20  miles  or  more.  These  tributaries  are 
usually  widely  bi'anching,  and  the  entire  watershed  displays  a  ])ei"fection  of 
drainage  such  as  does  not  occxir  within  the  limits  of  the  Wisconsin  drift. 
There  appears  to  be  on  the  main  stream,  and  also  on  many  of  the  tribu- 
taries, a  more  rapid  descent  in  tlie  headwater  ])ortions  than   in  the  lower 


ILLINOIS  RIVER  DRAINAGE  BASIN.  517 

courses,  a  feature  indicating  a  greater  maturity  of  drainage  than  is  charac- 
teristic cf  the  Wisconsin  drift;  for,  as  ah-eady  indicated^  several  of  the  large 
tributaries  of  the  Illinois  within  the  limits  of  the  Wisconsin  drift  have  their 
most  rapid  descent  in  the  lower  portion,  the  headwater  portion  being  slug- 
gish and  imperfectl}-  drained.  These  contrasts  in  drainage  are  only  in  part 
due  to  the  natural  advantages  possessed  by  Spoon  River,  and  they  furnish 
an  impressive  line  of  evidence  of  the  difference  in  the  age  of  the  drift  sheets. 

SANGAMON    KIVER. 

The  Sangamon  River  has  a  larger  watershed  than  any  other  tributary 
of  the  Illinois.  However,  its  drainage  area,  estimated  at  5,670  square 
miles,  includes  extensive  plains  in  central  Illinois  which  are  inadequately 
drained,  but  which  may,  by  extensive  ditching,  be  drained  into  it. 

The  length  of  the  river  is  about  180  miles.  Its  source  is  in  the 
Bloomington  morainic  system  in  eastern  McLean  County,  at  an  altitude  of 
about  850  feet  above  tide,  or  about  430  feet  above  its  mouth  (the  mouth 
being  419  feet).  In  the  first  10  miles  it  makes  a  descent  of  120  feet,  thus 
leaving  about  300  feet  of  fall  for  the  remaining  170  miles  of  its  course. 
The  fall  is  far  from  regular,  there  being  sections,  often  several  miles  in 
length,  in  which  it  is  slight,  between  which  are  sections  with  more  rapid 
fall.  Thus  in  its  course  through  Sangamon  County,  a  distance  of  36  miles, 
it  falls  only  38  feet,  while  in  crossing  Menard  County,  immediately  below, 
it  falls  67  feet  in  a  distance  of  30  miles,  and  in  crossing  Macon  County, 
just  above  Sangamon,  it  falls  50  feet  in  about  30  miles.  In  the  lower  23 
miles,  where  it  crosses  the  Illinois  bottoms,  its  fall  is  only  16  feet. 

The  main  stream  flows  for  about  90  miles  within  the  limits  of  the 
Wisconsin  drift,  leaving  that  drift  a  few  miles  west  of  the  city  of  Decatur. 
In  this  portion  of  its  course  it  receives  no  tributaries  of  importance,  its 
immediate  watershed  being  only  15  or  20  miles  in  width.  As  previously 
indicated,  it  follows  the  west  border  of  the  Cerro  Grordo  moraine  for  fully 
30  miles  below  the  village  of  Mahomet,  and  that  moraine  constitutes  the 
east  border  of  its  watershed.  Its  channel  is  but  20  to  30  feet  in  average 
depth  in  the  first  60  miles  of  its  course,  but  in  the  next  30  miles,  in  which 
it  crosses  the  Shelbyville  morainic  system  and  the  elevated  inner  slope  of 
the  moraine,  it  has  trenched  to  a  depth  of  75  feet  or  more.  Upon  leaving 
the  Shelbyville  system  it  again  enters  a  shallow  valley,  scarcely  50  feet  in 


518  THE  ILLINOIS  GLACIAL  LOBE. 

depth,  and  this  it  maintains  nearly  to  tlie  mouth  of  the  stream.  The 
depth,  however,  is  increased  nearly  to  100  feet  in  portions  of  the  course 
between  Springfield  and  Petersburg.  The  portion  lying  outside  the  Wis- 
consin drift  sheet,  although  generally  shallow,  is  much  wider  than  the 
portion  within  the  limits  of  that  drift  sheet,  and  bears  evidence  of  having 
been  pai-tially  opened  prior  to  the  Wisconsin  stage  of  glaciation. 

The  amount  of  excavation  accomplished  prior  to  the  Wisconsin  stage 
is  especially  well  shown  on  tributaries  of  the  Sangamon  River,  both  north 
and  south  of  the  main  stream,  which  in  some  cases  have  been  beheaded 
because  of  the  Wisconsin  deposits.  Thus  Lake  Fork,  a  small  stream  lead- 
ing- northwestward  from  the  border  of  the  Wisconsin  drift  in  western  Macon 
County,  has  a  valley  about  20  feet  in  depth  and  fully  one-half  mile  in 
width,  which  was  apparently  formed  entirely  before  the  Wisconsin  stage  of 
glaciation,  for  it  now  cai'ries  no  stream  adequate  to  erode  a  channel.  The 
Sangamon  River  and  several  of  its  tributaries  are  found  to  have  similar 
broad  shallow  valleys  bordering  naiTower  valleys  of  somewhat  greater  depth. 
By  affording  this  means  for  comparing  the  amount  and  kind  of  erosion 
carried  on  before  and  since  the  Wisconsin  invasion  the  Sangamon  watershed 
becomes  an  important  district  for  investigation. 

Several  tributaries  of  the  Saiigamon  have  their  sources  within  the 
limits  of  the  Wisconsin  drift,  among  which  may  be  mentioned  North  and 
South  Salt  creeks,  Kickapoo  Creek,  ^  and  thi-ee  headwater  branches  of  Sugar 
Creek.  Kickapoo  and  Sugar  creeks  join  Salt  Creek  a  few  miles  above  its 
mouth,  and  therefore  fall  within  the  limits  of  its  watershed.  South  Salt 
Creek  heads  on  the  outer  border  of  the  Bloomington  morainic  s}'stem,  in 
southeastern  McLean  County,  and  flows  southwestward  across  a  gently 
undulating  plain  to  its  junction  with  North  Salt  Creek,  about  5  miles  east 
of  Clinton.  North  Salt  Creek  has  its  source  between  the  two  large  ridges 
of  the  Blooming-ton  moi'ainic  system,  very  near  the  soiu'ce  of  the  Sangamon 
River.  It  passes  southward  through  the  outer  ridge  and  across  the  undu- 
lating plain  south  of  it  to  its  junction  with  the  South  Fork.  Each  of  these 
streams  has  a  length  of  25  or  30  miles  above  their  junction.  The  united 
stream  passes  westward  throvigh  the  Shelby  ville  moraine,  entering  the  outer 
border    plain  at    Kenney,    8   miles   southwest  of  Clinton.      The  genei-al 


'  Tliis  Kickapoo  Creek  should  lie  ilistinguisheil  fioin  a  stii'am  of  the  same  name  cnteriim:  tlie  Illi- 
nois at  Peoria. 


ILLINOIS  RIVER  DRAINAGE  BASIN.  519 

course  of  the  stream  continues  westward  to  its  junction  with  the  Sangamon 
River,  50  miles  below.  It  receives  Lake  Fork  Creek  from  the  south  about 
5  miles  above  Lincoln;  Kickapoo  Creek  from  the  north  about  4  miles  below 
Lincoln,  and  Sugar  Creek,  also  from  the  north,  about  12  miles  farther  down. 
Its  valley  is  much  broader  below  the  mouth  of  Lake  Fork  than  above,  and 
it  seems  probable  that  a  larger  stream  occupied  Lake  Fork  Valley  prior  to 
the  Wisconsin  invasion  than  occupied  Salt  Creek  Valley.  Indeed,  the  latter 
appears  to  be  almost  wholly  a  post- Wisconsin  stream  as  far  down  as  its 
junction  with  Lake  Fork. 

Kickapoo  Creek  finds  its  source  between  the  two  ridges  of  the  Bloom- 
ington  system,  a  few  miles  east  of  the  city  of  Bloomington.  Like  North 
Salt  Creek,  it  passes  southward  through  the  outer  morainic  ridge  and,  as 
previously  noted,  becomes  the  avenue  of  discharge  for  a  gravel  train  head- 
ing in  that  moraine.  It  passes  through  the  Shelbyville  moraine  near  the 
village  of  Waynesville  and  skii-ts  its  outer  border  for  a  few  miles  west, 
when  it  turns  southwestward  into  Salt  Creek,  entering  that  stream  about  10 
miles  from  its  point  of  departure  from  the  Shelbyville  moraine. 

The  several  headwater  branches  of  Sugar  Creek  find  their  sources  in 
the  depi-ession  between  the  two  main  ridges  of  the  Bloomington  system, 
and  pass  thence  southwestward  through  the  outer  moraine,  where  they 
become  the  avenue  of  discharge  for  the  trains  of  gravel  connected  with 
that  moraine.  The  several  branches  converge  upon  approaching  the  Shel- 
byville moraine  and  unite  in  the  midst  of  the  moraine.  Upon  emerging 
from  the  Shelbyville  moraine.  Sugar  Creek  Valley  is  sepai'ated  from  Kick- 
apoo by  an  interval  of  only  1^  miles,  and  this  is  largely  occupied  by  a 
plain  of  gravel  built  up  by  the  joint  work  of  the  two  streams.  Instead  of 
uniting  with  Kickapoo  Creek,  however.  Sugar  Creek  turns  westward,  and 
joins  Salt  Creek  about  12  miles  below  the  mouth  of  Kickapoo  Creek. 

Sangamon  River  receives  one  important  tributary  from  the  south, 
known  as  South  Fork.  It  drains  the  greater  part  of  Christian  County,  and 
enters  the  river  in  Sangamon  County,  immediately  east  of  the  city  of 
Springfield.  An  eastern  branch  of  South  Fork,  known  as  Flat  Fork,  has 
evidently  been  beheaded  because  of  the  Wisconsin  drift,  in  a  manner  simi- 
lar to  that  of  Lake  Fork.  The  stream  has  its  present  head  in  the  outer 
border  of  the  Shelbyville  moraine,  but  finds  a  broad  shallow  valley,  far 
out  of  proportion  to  its  needs,  down  which  it  passes  to  the  Sangamon  River. 


520  THE  ILLINOIS  GLACIAL  LOBE. 

The  average  width  of  the  valle}'  is  nearly  one-half  mile,  but  its  depth  is 
only  about  20  feet. 

The  Sangamon  River  also  receives  the  drainage  from  a  plain  on  its 
southwest  border  south  and  west  from  Springfield.  This  plain  shows  a  per- 
ceptible descent  toward  the  river,  and  the  present  divide  between  the  tribu- 
taries of  the  Sangamon  and  several  streams  which  flow  directly  westward 
to  the  Illinois  apparently  follows  nearly  the  line  of  a  preglacial  rock  divide. 
With  this  exception  the  borders  of  the  Sangamon  watershed  appear  to  be 
determined  by  accumulations  of  drift. 

CROOKED   CREEK. 

This  western  tributary  of  the  Illinois,  which  enters  about  14  miles 
below  the  mouth  of  the  Sangamon,  drains  an  area  of  nearly  1,400  square 
miles.  Its  watershed  lies  immediately  southwest  of  the  Spoon  River  water- 
shed. It  extends  on  the  northwest  nearly  to  the  bluff  of  the  Mississippi, 
there  being  one  tributary  in  northern  Hancock  County,  from  which  the 
Mississippi  bluff  is  distant  less  than  5  miles. 

The  main  stream  has  a  southeastward  course  from  eastern  Hancock 
County  to  its  mouth,  a  distance  of  60  miles.  No  important  tributaries  enter 
fi'om  the  west,  but  several  creeks  lead  into  it  from  the  east,  which  have 
lengths  of  15  to  20  miles  or  more.  These  eastern  tributaries  present  a 
remarkable  parallelism,  and  take  a  nearly  uniform  direction  about  S.  65°  W. 
As  previously  indicated,  one  of  these  tributaries,  known  as  East  Crooked 
Creek,  occupies  a  valley  which  continues  beyond  this  watershed  in  direct 
course  to  the  Mississippi,  and  which  is  thought  to  have  been  formed  by  a 
subglacial  stream.  (See  discussion  of  Big  Meadow  channel,  p.  481.) 
Shallow  channels  may  also  have  been  opened  by  the  same  agency  along 
other  eastern  tributaries,  and  have  occasioned  their  remarkably  direct  and 
parallel  courses. 

For  a  few  miles  near  its  mouth  the  course  of  Crooked  Creek  has  been 
determined  by  a  preglacial  drainage  line,  but  elsewhere  the  drainage 
appears  to  be  nearly  independent  of  preglacial  lines.  A  portion  of  the 
divide  between  its  watershed  and  that  of  Spoon  River  follows  a  low  till 
ridge.  This  ridge,  however,  is  only  a  partial  cause  for  the  divide,  since 
the  general  altitude  and  slo]jes  on  its  borders  are  such  as  to  have  located 
tlie  line  of  separation  between  the  watersheds  at  about  the  present  divide. 


ILLINOIS  EIVER  DEAII^AGE  BASIN  521 


MCKEE'S    CREEK. 


This  western  tributary  of  the  lUiiiois  enters  about  18  miles  below  the 
mouth  of  Crooked  Creek,  and  has  an  estimated  drainage  area  of  472  square 
miles.  Its  general  course  is  southeastward  from  eastern  Adams  Countv, 
across  southern  Brown  and  northeastern  Pike  counties.  Within  a  mile  of  its 
mouth  it  is  joined  by  South  McKee's  Creek,  which  drains  the  northeast 
part  of  Pike  County. 

The  greater  part  of  the  divide  between  McKee's  Creek  watershed  and 
the  small  streams  leading  directly  west  into  the  Mississippi  follows  a  series 
of  ridges  which  belong  to  the  system  formed  at  the  margin  of  the  Illinoian 
drift  sheet.  Not  only  have  these  ridges  been  influential  in  determining  the 
position  of  this  divide,  biit,  as  already  indicated,  they  have  governed  to 
some  extent  the  courses  of  the  small  streams  directly  ti-ibutary  to  the 
Mississippi.  The  divide  between  Crooked  Creek  and  McKee's  Creek '  is 
nearly  free  from  drift  ridges,  and  stands  but  little  higher  than  the  borders 
of  McKee's  Creek  Valley.  Its  elevation  is,  however,  ^perceptibly  greater 
than  that  of  the  immediate  borders  of  Crooked  Creek.  The  thickness  of 
the  drift  is  generally  sufficient  throughout  this  watershed  to  fill  the  pre- 
glacial  drainage  lines  and  render  it  necessary  to  develop  lines  along  new 
courses. 

INDIAN,   MAUVAISE   TBRRE,    AND   BIG   SANDY   CREEKS. 

Indian  Creek  is  one  of  several  small  eastern  tributaries  of  the  Illinois 
entering  the  portion  of  the  valley  south  of  the  mouth  of  the  Sangamon. 
It  has  a  di-ainage  area  of  about  290  square  miles,  situated  mainly  in  north- 
ern Morgan  County.  Its  lower  10  miles  are  occupied  in  crossing  the  Illinois 
River  bottoms,  where  it  has  little  drainage  outside  its  immediate  channel. 
Its  watershed  on  the  uplands  has  a  breadth  of  about  9  miles  and  a  length  of 
fully  20  miles.  The  general  course  of  drainage  is  directly  westward,  across 
a  gently  sloping  plain,  and  is  independent  of  jjreglacial  di-ainage  lines. 
The  divide  at  the  east,  however,  is  probably  a  preglacial  rock  divide. 

Mauvaise  Terre  Creek  drains  a  naiTOw  strip  immediately  south  of  the 
Indian  Creek  watershed  and  has  a  drainage  area  of  275  square  miles.  It 
includes  a  strip  leading  westward  across  central  Morgan  County  and  north- 
ern Scott  County,  whose  average  width  is  scarcely  more  than  8  miles,  but 
whose  length  is  about  30  miles.     Like  Indian  Creek,  its  course  seems  to 


522  THE  ILLINOIS  GLACIAL  LOBE. 

have  been  determined  by  the  slope  of  a  di-ift  plain  and  is  apparently  inde- 
pendent of  preglacial  lines. 

Big  Sandy  Creek,  the  next  succeeding  eastern  tributary  of  the  Illinois, 
has  a  drainage  area  of  about  190  square  miles.  Its  watershed  is  broader 
than  either  of  the  two  preceding,  but  is  much  shorter,  its  extreme  length 
from  east  to  west  being  scarcely  more  than  18  miles.  It  comprises  a  dis- 
trict lying  somewhat  below  the  g-eneral  level  of  the  neighboring  watershed. 
This  fact,  together  with  the  absence  of  rock  outcrops  in  the  portion  of  the 
Illinois  bluffs  immediatel}^  north  of  its  mouth,  renders  it  probable  that  a 
preglacial  drainage  line  traversed  the  midst  of  its  watershed,  though  in  a 
course  not  precisely  coincident  with  that  of  the  present  stream. 

APPLE    CREEK. 

Apple  Creek  has  a  drainage  area  of  about  500  square  miles,  which 
includes  southeastern  Morgan,  northern  Greene,  and  northwestern  Macoupin 
counties.  Its  course  is  southwestward,  and  the  watershed  has  a  length  of 
about  40  miles.  The  greatest  breadth  is  about  15  miles.  Its  lower  course 
appears  to  be  along  the  line  of  a  preglacial  valley,  but  the  headwater 
portion  and  also  the  majority  of  the  tributaries  show  little  dependence  upon 
preglacial  lines.  The  drift  is  comparatively  thin  over  much  of  the  water- 
shed, and  streams  have  cut  down  into  the  underlying  rocks  at  many  points. 

MAOOUPIN    CREEK. 

Macoupin  Creek  is  the  most  important  eastern  tributary  south  of  the 
Sangamon  River,  its  drainage  area  being  nearly  1,000  square  miles.  It 
drains  the  greater  part  of  Macoupin  County  and  a  portion  of  the  neighbor- 
ing counties  on  the  east  and  west.  Its  watershed  is  widely  branching  in 
the  middle  portion  and  tapers  toward  either  end,  giving  a  broadly  ovate 
outline.  With  the  exception  of  the  headwater  portion  above  Carlinville, 
the  main  stream  apparently  has  its  course  determined  by  a  preglacial  line, 
there  being  a  broad  depression,  deeply  filled  with  drift,  tlu-ough  which  the 
creek  takes  its  course.  The  tributary  streams  appear  to  be  largely  inde- 
pendent of  preglacial  lines.  The  extent  of  the  watershed  on  the  north  and 
south  appears  to  be  detei'mined  in  large  part  by  preglacial  divides,  but  the 
influence  of 'preglacial  divides  is  less  apparent  at  the  eastern  border  of  the 
watershed. 


KASKASKIA  RIVEE  DRAINAGE  BASIN,  523 


OTTKli    CREEK. 


This  small  eastern  tributary  of  the  Illinois  drains  an  area  of  about  100 
square  miles  embraced  between  the  mouth  of  Macoupin  Creek  and  the 
elevated  rock  ridge  which  forms  the  bluff  of  the  Mississippi  and  Illinois  in 
southern  Jersey  County.  It  apparently  follows  in  a  general  way  a  pre- 
glacial  drainage  line  having  about  the  same  watershed. 

KASKASKIA   RIVER   DRAINAGE  BASIN. 

KASKASKIA   RIVER. 

The  Kaskaskia  or  Okaw  is  the  principal  I'iver  traversing  southern 
Illinois.  With  a  length  of  180  miles,  it  drains  neai-ly  6,000  square  miles. 
Its  source  is  in  the  Champaign  morainic  system  immediately  west  of  the 
city  of  Champaign,  at  an  altitude  of  about  730  feet  above  tide;  it  enters 
the  Mississippi  near  Chester,  in  Randolph  County,  at  an  altitude  of  342 
feet.  Its  descent  is  generally  gradual,  the  most  rapid  section  of  its  course 
being  in  its  passage  thi'ough  Moultrie  County,  where  it  makes  a  descent  of 
55  feet  in  about  18  miles,  or  3  feet  to  the  mile.  In  the  headwater  portion 
there  is  a  fall  of  only  110  feet  in  the  first  50  miles.  In  places  there  are 
pools  several  miles  in  length,  the  most  conspicuous  of  these  being  foimd  in 
St.  Clair  County,  where,  in  a  distance  of  20  miles,  the  fall  is  scarcely  1 0  feet. 

The  stream  is  subject  to  great  variations  in  volume,  for  it  drains  a 
region  in  which  the  substrata  are  of  compact  clay,  which  promotes  a  rapid 
run  off,  and  furnishes  but  little  water  in  seasons  of  drought.  A  rise  of  20 
feet  in  its  lower  course  is  not  rare,  and  its  flood  plain  has  been  built  nekrly 
to  that  height  above  the  stream  bed. 

The  upper  80  miles  of  this  stream  lies  within  the  limits  of  the  Wis- 
consin drift.  The  stream  emerges  from  the  Shelbyville  moraine  at  the  city 
of  Shelbyville.  In  this  headwater  portion  there  are  no  noteworthy  ti-ibu- 
taries,  and  the  watershed  has  a  breadth  of  only  10  to  20  miles.  The 
channel  is  narrow  and  shallow  from  the  source  down  nearly  to  the  inner 
border  of  the  Shelbyville  morainic  system.  There  it  becomes  deeper,  with 
a  narrow  trench  having  an  average  depth  of  nearly  75  feet.  Near  its  point 
of  emergence  from  the  Shelbyville  system  two  railway  bridges  extend  from 
bluff  to  bluff,  thus  avoiding  the  necessity  for  a  descent  into  the  valley,  and 
yet  the  bridges  are  only  about  one-fourth  mile  in  length. 


524  THE  ILLINOIS  GLACIAL  LOBE. 

Upon  eutering  the  older  drift  the  valley  continues  small  for  a  few  miles, 
but  is  perceptibly  increased  in  size  below  the  point  of  entrance  of  Robinson 
Creek.  This  stream  appears  to  follow  the  lower  course  of  a  drainage  line 
whose  former  headwater  portion  has  been  concealed  by  the  Shelbyville  drift 
sheet.  Its  valley  has  a  breadth  of  nearly  a  half  mile,  and  this  breadth 
characterizes  the  portion  of  the  Kaskaskia  immediately  below  its  mouth. 
Upon  entering  Fayette  County  the  river  soon  opens  into  a  broad  preglacial 
valley  whose  course  farther  north  has  been  concealed.  The  valley  has  a 
width  of  about  3  miles  near  Vandalia,  but  increases  to  greater  width  farther 
south.  Masked  as  it  is  by  the  drift,  it  presents  the  appearance  of  a  broad 
shallow  basin  rather  than  a  river  valley.  This  basin-like  valley  continues 
nearly  to  the  mouth  of  the  stream,  where  the  width  contracts  abruptly  to 
about  a  mile  upon  entering  the  Eocarboniferous  limestone  which  there 
borders  the  Mississippi  Valley. 

This  stream  receives  but  one  noteworthy  eastern  tributary — Crooked 
Creek — and  two  western  tributaries — rShoal  Creek  and  Silver  Creek. 
Crooked  Creek'  is  relatively  unimportant,  as  it  drains  only  a  narrow  strip, 
35  or  40  miles  in  length,  leading  from  north-central  Marion  County  south- 
westward  past  Salem  and  Centralia  and  entering  the  Kaskaskia  a  few  miles 
below  Carlyle.  Coal  shafts  at  Salem,  Odin,  and  Sandoval  show  the  pres- 
ence of  a  preglacial  valley  on  the  north  border  of  this  watershed,  with  bed 
100  feet  or  more  below  the  present  surface,  but  the  present  stream  flows 
through  a  region  of  comparatively  thin  drift. 

SHOAL    CREEK. 

Shoal  Creek  has  a  drainage  area  of  about  1,000  square  miles,  or  one- 
sixth  the  entire  watershed  of  the  Kaskaskia  River.  Its  watershed  embraces 
the  greater  part  of  Montgomery  and  Bond  counties  and  the  western  part  of 
Clinton  County.  The  stream  enters  the  Kaskaskia  in  the  southwest  part  of 
Clinton  County,  about  20  miles  below  Carlyle.  In  the  headwater  portions 
there  are  three  streams,  known  as  West,  Middle,  and  East  Shoal  creeks. 
West  and  Middle  Shoal  creeks  are  each  about  20  to  25  miles  in  length  and 
unite  near  Walshville  in  southwestern  Montgomery  County.  The  united 
stream  below  that  point  is  known  as  West  Fork  to  its  junction  with  East 
Shoal  Creek,  20  miles  farther  south.     East  Shoal  Creek  has  a  length  of 


This  stream  should  not  be  confused  with  one  of  the  Siime  name  that  enters  the  Illiuois  River. 


KASKASKIA  EIVEK  DRAINAGE  BASIN.  525 

about  40  miles,  but  drains  a  mucli  narrower  strip  than  that  of  West  Fork. 
Below  the  junction  of  the  East  and  West  forks  the  stream  has  a  length  h\ 
direct  course  of  about  25  miles. 

This  watershed  has  a  perceptible  southward  descent,  the  altitude  at  the 
headwaters  being  700  to  750  feet  at  tide  and  at  the  mouth  only  400  feet. 
The  mouth  of  the  creek  is  but  380  feet.  The  tlii-ee  streams  have  each  formed 
channels  50  to  75  feet  or  more  in  depth  and  nearly  one-fourth  mile  in  average 
width  in  their  passage  through  southern  Montgomerj^  County.  A  similar 
depth  is  maintained  as  far  down  as  the  junction  of  the  East  and  West  forks 
near  Greenville.  Below  this  point  the  valley  is  more  shallow  and  the 
stream  soon  enters  the  Kaskaskia  Basin,  where  its  valley  is  but  little  lower 
than  the  basin  plain. 

East  Shoal  Creek  is  bordered  closely  on  the  east  throughout  its  entire 
length  by  a  system  of  drift  knolls  and  ridges  which,  as  previously  described, 
attain  great  prominence  in  eastern  Montgomery  County.  Shoal  Creek 
passes  through  a  break  in  this  system  of  ridges  just  below  the  junction  of 
the  East  and  West  forks,  beyond  which  its  course  is  largely  independent  of 
drift  ridges.  Middle  Shoal  Creek  winds  about  among- pi'ominent  drift  knolls 
near  Hillsboro,  and  West  Shoal  Creek  is  deflected'  eastward  by  a  ridge  of 
drift  at  its  junction  with  Middle  Shoal  Creek.  With  these  exceptions  the 
streams  are  not  markedly  deflected  by  drift  aggregations.  They  pursue, 
as  a  rule,  nearly  direct  southward  courses,  following  the  slope  of  their 
watershed. 

Their  courses  appear  to  be  mainly  independent  of  preglacial  drainage 
lines.  East  Shoal  Creek  touches  the  line  of  a  deep  preglacial  valley  near 
Grreenville,  but  above  that  point  it  has  opened  a  new  course,  in  places 
trenching  into  the  rock.  Even  the  lower  course  seems  to  be  largely  inde- 
pendent of  any  preglacial  line  of  drainage. 

SILVER    CREEK. 

Silver  Creek  has  its  source  in  southeastern  Macoupin  County  and 
flows  nearly  due  south  its  entire  length  of  fully  50  miles,  crossing  the 
eastern  part  of  Madison  and  St.  Clair  counties.  Its  watershed  is  scarcely 
10  miles  in  average  width,  and  has  an  area  of  about  500  square  miles.  At 
the  source  of  the  stream  the  altitude  is  fully  650  feet,  but  the  watershed 
descends  within  10  miles  to  about  550  feet,  and  in  the  next  15  miles  to 


526  THE  ILLINOIS  GLACIAL  LOBE. 

about  500  feet  above  tide,  while  the  stream  falls  to  about  450  feet.  In  the 
lower  half  the  watershed  is  diversified  by  drift  ridges  and  knolls  which  rise 
abruptly  in  some  cases  to  a  height  of  75  feet  or  more  above  border  dis- 
tricts. These  ridges  for  a  few  miles  in  southeastern  Madison  County  con- 
stitute the  east  border  of  the  watershed,  but  just  south  of  the  line  of 
Madison  and  St.  Clair  counties  the  stream  passes  through  the  main  belt  of 
ridges,  and  has  but  few  prominent  ridges  and  knolls  on  its  east  side  below 
that  point.  At  its  mouth  the  stream  has  an  elevation  of  only  370  feet,  and 
the  border  districts,  aside  from  knolls,  stand  scarcel}^  400  feet  above  tide. 
This  sti-eam,  like  Shoal  Creek,  appears  to  be  largely  independent  of 
preglacial  drainage  lines.  It  trenches  into  the  rock  at  numerous  points 
along  its  course,  and  its  immediate  bluifs  stand  at  the  general  level  of  bor- 
dering uplands.  There  may,  however,  have  been  a  preglacial  divide  near 
the  headwaters  of  the  creek. 

BIG  MUDDY  RIVER  DRAINAGE  BASI]Sr. 

The  only  remaining  important  tributary  of  the  Mississippi  is  the  Big 
Muddy,  a  stream  draining  about  2,400  square  miles  in  the  low  district  lying 
north  of  the  "  Ozark  Ridge."  It  is  the  line  of  discharge  for  the  greater 
part  of  Williamson,  Franklin,  Jefferson,  Perry,  and  Jackson  counties  and 
the  southeastern  part  of  Washington  and  the  southern  part  of  Marion 
County.  The  lower  20  miles  of  its  course  lies  within  the  Mississippi 
bottom. 

With  the  exception  of  the  elevated  district  on  the  south  border,  which 
stands  600  to  800  feet  above  tide,  this  watershed  has  few  points  rising 
above  550  feet.  It  stands  mainly  between  400  and  500  feet  above  tide. 
The  immediate  borders  of  the  main  valley  fall  below  400  feet,  and  the 
mouth  of  the  stream  at  low  water  in  the  Mississippi  is  but  320  feet. 

The  principal  ti-ibutaries  of  Big  Muddy  River  are  Beaucoup  Creek  and 
Little  Muddy  River,  which  drain  the  western  side  of  its  watershed.  An 
eastern  tributary — Crab  Orchard  Creek — drains  about  250  square  miles  of 
the  district  bordering  the  ' '  Ozark  Ridge." 

Tlu'oughout  the  greater  portion  of  its  course  Big  Mudd}-  River  occu- 
pies a  preglacial  line  of  drainage,  and  meanders  about  in  the  broad  bottoms 
which  have  been  filled  with  drift  and  alluvium  to  an  elevation  of  50  to  100 
fe(^t  or  more  above  the  rock   bottom.     Just  below  Murplivsboro,  liowever, 


SALINE  EIVEE  DEAINAGE  BASIN.  527 

the  valley  becomes  constricted  to  a  width  of  about  a  mile  iu  its  passage 
through  the  elevated  ridge  which  there  borders  the  Mississippi  Valley. 
Little  Muddy  River  and  Beaucoup  Creek,  with  their  principal  tributaries 
also  flow  through  broad  preglacial  channels  which  carry  heavy  deposits  of 
drift  and  alluvium. 

Possibly  the  watershed  of  Crab  Orchard  Creek  has  received  important 
modifications  as  a  result  of  glaciation.  The  headwater  portion  of  the 
South  Fork  of  Saline  River,  a  tributary  of  the  Ohio,  leads  down  directly 
toward  Crab  Orchard  Creek  from  the  elevated  portion  of  the  "  Ozark 
Ridge  "  to  a  low  plain  filled  to  a  considerable  depth  with  glacial  deposits. 
It  there  turns  abruptly  eastward,  following  nearly  the  glacial  boundary. 
It  probably  continued  northwestward  into  Crab  Orchard  Creek  in  preglacial 
times.  A  considerable  area  in  northwestern  Williamson  County  also  has 
been  filled  to  such  a  depth  with  glacial  drift  that  the  preglacial  lines  are 
completely  concealed.  Throughout  the  greater  part  of  the  Big  Muddy 
watershed  the  drift  is  very  thin,  and  rock  divides  separating  the  preglacial 
drainage  areas  are  plainly  discernible. 

SALIlSrE    RIVER    DRAINAGE   BASIN. 

This  small  watershed  tributary  to  the  Ohio  drains  the  portion  of  south- 
eastern Illinois  immediately  north  of  the  "  Ozark  Ridge."  The  South  Fork 
follows  closely  the  base  of  the  ridge,  receiving  small  tributaries  which 
descend  the  slope  of  the  ridge.  The  lower  course  of  the  main  stream  is 
also  along  the  base  of  the  ridge.  The  Middle  Fork  rises  in  southeastern 
Franklin  County  and  takes  a  southeastward  course  past  Harrisburg  into  the 
South  Fork,  draining  much  of  Saline  County.  The  North  Fork  has  its 
source  in  western  Hamilton  County  and  leads  southeastward,  draining  the 
south  half  of  Hamilton,  the  northeast  part  of  Saline,  the  southwest  part  of 
White,  and  the  west  part  of  Gallatin  County,  joining  the  South  Fork  at 
the  town  of  Equality,  about  12  miles  west  of  Shawneetown. 

These  three  forks  of  the  Saline  River,  and  also  their  principal  tribu- 
taries, are,  in  the  main,  reestablished  along  preglacial  lines  and  take  mean- 
dering courses  through  broad  valleys  which  have  been  filled  to  an  elevation 
of  50  to  100  feet  or  more  above  their  rock  bottoms.  As  above  noted,  a 
small  part  of  the  watershed  of  South  Fork  has  probably  been  added  to 
this  drainage  system  as  a  result  of  glaciation,  but  with  this  exception  no 


528  THE  ILLINOIS  GLACIAL  LOBE. 

deflections  worthy  of  note  have  been  observed.  The  South  Fork  follows 
nearly  the  glacial  boundary  throughout  much  of  its  length,  but  apparently 
occujiies  a  preglacial  channel. 

CACHE   RIVER. 

A  change  of  some  consequence  has  occurred  in  the  Tertiary  lowland 
in  southern  Illinois.  The  Ohio  at  one  time  discharged  either  wholly  or  in 
part  through  the  "Cache  Valley,"  which  crosses  southern  Illinois  a  few  miles 
north  of  the  present  course  of  the  Ohio.  Its  point  of  connection  with  the 
Cache  Valley  was  immediately  north  of  Metropolis,  Illinois,  where  for  a 
distance  of  4  or  5  miles  a  clay  deposit  has  accumulated  in  the  line  of  the 
old  valley.  The  surface  of  this  clay  deposit  stands  only  about  75  feet 
above  the  present  stream  and  is  much  lower  than  the  surface  of  the  Tertiary 
deposits  on  either  side.  Wells  indicate  that  the  clay  has  sufficient  depth  to 
extend  to  river  level,  and  it  may  extend  much  lower.  The  surface  of  this 
clay  deposit  presents  much  less  erosion  than  that  of  the  bordering  Tertiary 
lowland  and  evidently  is  of  far  more  recent  date.  Judging-  from  the 
amount  of  erosion  displayed  it  is  no  older  than  the  Illinoian  drift  sheet.  It 
may  possibly  be  as  recent  as  the  white  clay  of  southern  Illinois,  which 
seems  referable  to  the  lowan  stage  of  glaciation.  It  is  not  known  as  yet 
whether  this  channel  formerly  constituted  the  sole  line  of  discharge  for  the 
Ohio.  Possibly  the  river  divided  its  waters  between  the  Cache  channel  and 
its  present  channel.  The  cause  for  the  filling  which  led  to  the  abandon- 
ment of  this  valley  by  the  Ohio  is  not  clearly  understood. 

The  Ohio  River  falls  within  the  limits  of  a  district  covered  by  another 
report,  hence  it  is  not  taken  up  here. 

WABASH  RIVER  DRAIISTAGE  BASIN. 

The  large  drainage  basin  of  the  Wabash  River,  with  an  area  of  about 
33,000  square  miles,  extends  from  western  Ohio  westward  across  the  central 
portion  of  Indiana  and  thence  southward  to  the  Ohio,  embracing  on  the 
west  side  of  its  watershed  a  considerable  portion  of  southeastern  Illinois. 
About  one-half  of  this  drainage  area  was  covered  by  the  Illinois  glacial 
lobe,  and  many  important  changes  have  resulted  from  its  occupancy  of  the 
region.  Indeed,  there  appears  to  be  very  little  similarity  of  outline  between 
the  jjresent  watershed  and  the  watershed  which  in  preglacial  times  had  its 


WABASH  KIVEK  DKAINAGE  BASIN.  529 

discharge  through  the  lower  cotu'se  of  the  Wabash.  The  westward-flowing 
portion  of  the  Wabash,  with  its  several  tributaries,  traverses  a  district  lying 
mainly  outside  the  limits  of  the  Illinois  lobe  and  appears  to  be  entirely 
independent  of  preglacial  drainage  lines,-  for  the  drift  deposits  have  been 
built  up  to  a  level  above  the  preglacial  rock  divides.  The  headwater  por- 
tions of  White  and  East  White  rivers,  which  are  the  principal  tributaries  of 
the  Wabash,  seem  also  to  be  very  largely  independent  of  preglacial  lines. 
There  remain  only  the  lower  courses  of  the  Wabash,  and  of  tributaries 
entering  below  the  great  bend  near  Covington,  Indiana,  which  are  governed 
to  any  considerable  extent  by  the  preglacial  lines  of  drainage.  These  all 
fall  within  the  limits  of  the  Illinois  lobe  or  of  unglaciated  districts  immedi- 
ately outside. 

Only  tlie  tributaries  of  the  Wabash  which  enter  within  the  limits  of 
the  Illinois  glacial  lobe  are  discussed  in  this  place.  The  remainder  of  the 
watershed  falls  within  the  limits  of  a  district  covered  by  another  report, 
now  in  preparation. 

THE   PREGnACIAL    WABASH    VALLEY. 

The  Wabash  River  enters  a  preglacial  valley  just  above  the  city  of 
Lafayette,  which  probably  furnished  a  line  of  discharge  for  a  considerable 
territory  on  the  north  and  west.  The  river,  however,  remains  in  this 
preglacial  valley  for  only  a  few  miles;  it  soons  turns  southwestward  across 
a  rock  point,  while  the  preglacial  valley  apparently  takes  a  longer  route  to 
the  west  and  south,  coming  to  the  river  at  its  great  bend  near  Covington. 
From  Covington  southward  the  stream  follows  nearly  the  line  of  a  preglacial 
valley  to  its  mouth,  though  in  a  few  places  it  cuts  off"  rock  jjoints  which 
projected  into  the  preglacial  valley. 

Above  Terre  Haute  this  preglacial  valley  has  been  opened  only  a  part 
of  its  width  by  the  present  stream,  yet  it  shows  a  breadth  of  2  to  4  miles. 
Below  Terre  Haute  the  bottoms  of  the  present  stream  extend  from  bluff  to 
Huff  of  the  preglacial  valley.  The  breadth  increases  from  about  6  miles  at 
Terre  Haute  to  fully  15  miles  near  the  junction  of  the  Wabash  with  the 
Ohio. 

Few  data  have  been  obtained  concerning  the  elevation  of  the  rock 
bottom,  but  these  uniformly  indicate  a  level  considerably  below  that  of  the 
present  stream.     So  far  as  collected,  they  do  not  show  a  descent  in  passing 

MON  XXXVIII 34 


530  THE  ILLINOIS  GLACIAL  LOBE. 

from  north  to  south,  but  they  are  scarcely  sufficient  to  prove  a  warping  of 
the  vallev  floor.  A  boring  in  the  abandoned  channel  west  of  Lafayette 
enters  rock  at  the  remarkably  low  altitude  of  about  300  feet  above  tide, 
while  at  Terre  Haute  several  borings  made  in  the  middle  part  of  the  valley 
enter  rock  at  345  to  360  feet  above  tide.  Between  these  two  points  borings 
at  Clinton  and  Montezuma  enter  rock  at  an  elevation  slightly  higher  than  at 
TeiTe  Haute.  The  elevation  of  the  rock  floor  at  Shawneetown,  Illinois, 
just  below  the  mouth  of  the  Wabash,  is  shown  by  an  oil  boring  to  be  but 
240  feet  abo^'e  tide.  As  this  boring  was  made  near  the  border  of  the 
vallev,  the  rock  floor  may  there  reach  a  still  lower  elevation. 

MINOB  DEFLECTIONS   OF   THE   WABASH. 

At  several  points  the  Wabash  makes  slight  deflections  from  its  broad 
valley  to  cross  projecting  points  of  the  preglacial  bluft',  the  most  notable 
instances  being  just  above  the  city  of  Vincennes,  Indiana,  and  a  few  miles 
below  New  Harmony.  In  each  place  the  broad  valley  of  the  Wabash 
passes  around  the  western  side  of  the  projecting  point,  while  the  sti-eam 
cuts  across  in  a  somewhat  narrow  valley.  It  is  not  entu-ely  certain  that 
these  deflections  are  due  to  glaciatiou.  Possibly  they  have  been  caused  by 
encroachments  of  the  stream  upon  the  rock  divides  in  a  manner  suggested 
in  explanation  of  the  deflections  of  the  Mississippi  south  of  tlie  limits  of 
glaciation.  The  question  of  the  cause  of  the  deflection  must  for  the  present 
remain  open. 

LITTLE   WABASH   RIVEU. 

This  western  tributary  of  the  Wabash,  which  drains  about  3,000  square 
miles  of  southeastern  Illinois,  enters  the  river  only  8  miles  by  direct  line 
from  its  junction  with  the  Ohio.  Its  source  is  in  the  Shelbyville  moraine 
in  southwestern  Coles  County,  and  its  course  is  slightly  west  of  south  for 
50  miles,  to  northern  Clay  County,  beyond  which  point  it  is  east  of  south 
through  Cla}-,  eastern  Wayne,  and  eastern  White  counties,  a  distance  by 
direct  line  of  about  75  miles.  Its  most  important  tributary  is  Skillet  Fork, 
which  enters  from  the  west  near  Carnii.  The  lengtli  of  this  tributary  is 
about  65  miles,  not  including  the  windings  of  the  stream,  and  it  has  a 
watershed  of  nearly  1,000  square  miles. 

The  watershed  of  tlie   Little  Wabasli,  including  tliis  large   tributary, 


WABASH  KIVEJR  DRAINAGE  BASIN.  531 

has  an  ovate  form,  its  middle  portion  being  much  broader  than  the  upper 
and  lower  portions.  It  extends  on  the  west  to  the  watershed  of  the 
Kaskaskia,  on  the  south  to  that  of  Saline  River,  and  on  the  east  to  the 
Embarras  and  Bon  Pas  watersheds.  The  elevation  of  the  headwaters  of 
the  main  stream  is  about  700  feet,  but  the  watershed  falls  to  about  600  feet 
in  the  30  miles  to  Efiling-ham,  to  about  500  feet  in  the  next  30  miles  to 
Louisville,  and  to  about  450  feet  in  the  lower  half  The  elevation  of  the 
mouth  of  the  stream  is  323  feet  above  tide.  The  headwaters  of  Skillet 
Fork  are  only  about  550  feet,  thus  giving  a  fall  of  but  100  feet  in  the 
watershed  in  passing  across  the  broad  middle  portion  from  northwest  to 
southeast. 

The  main  stream  is  largely  independent  of  preglacial  lines  in  its  upper 
40  or  50  miles,  but  the  remainder  of  its  course  is  determined  by  a  broad 
preglacial  valley,  except  for  a  short  distance  just  below  Carmi,  where  it  cuts 
across  a  projecting  spur  of  hills  leading  in  from  the  west.  This  valley,  like 
other  valleys  in  that  region,  has  been  filled  in  its  lower  course  with  drift 
and  alluvium  to  a  level  perhaps  100  feet  above  its  rock  bottom.  It  thus 
covers  low  projecting  points  of  the  bluffs,  and  these  are  in  some  cases 
touched  by  the  present  stream,  but  the  spur  of  hills  near  Carmi  rises 
much  above  the  level  of  the  valley  filling.  The  cause  of  the  deflection  of 
the  stream  across  it,  like  that  of  similar  deflections  on  the  Wabash,  has  not 
been  satisfactorily  determined.  The  small  tributaries  of  Little  Wabash 
usually  enter  this  valley  through  preglacial  lines,  but  their  headwaters  are 
somewhat  independent  of  the  preglacial  drainage.  Skillet  Fork  and  its 
chief  tributaries  occupy  preglacial  valleys  throughout  much  of  their  length. 

BON    PAS    EIVEE. 

This  small  western  tributary  of  the  Wabash,  with  a  drainage  area  of 
about  250  square  miles,  is  the  line  of  discharge  for  a  district  in  Richland, 
Edwards,  and  Wabash  counties,  lying  between  the  watersheds  of  Little 
Wabash  and  Embarras  rivers.  Its  course  is  mainly  along  a  preglacial  line 
which  has  been  filled  in  its  lower  course  to  an  elevation  of  60  feet  or  ixiore 
above  the  rock  bottom.  The  watershed  outside  of  the  preg'lacial  line  of 
drainage  and  its  tributaries  has  only  a  very  thin  deposit  of  drift;  hence 
scarcely  any  change  of  drainage  has  resulted  from  the  glaciation. 


532  THE  ILLINOIS  GLACIAL  LOBE. 


PATOKA   RIVER. 


This  eastern  tributaiy  of  the  Wabash  has  a  di-ainag-e  area  of  nearly 
1,000  square  miles.  Its  watershed  is  long-  and  naiTow,  being-  about  80  miles 
in  length  and  less  than  15  miles  in  average  width,  and  lies  between  the 
watershed  of  East  White  River  and  the  watersheds  of  several  small  streams 
which  are  dii-ectly  tributary  to  the  Ohio.  The  interesting-  drainage  modi- 
fications which  resulted  in  the  production  of  the  present  Patoka  River  have 
already  been  considered  (pp.  98-102). 


WHITE    RIVER. 


The  entire  watershed  of  White  River  is  about  11,000  square  miles. 
Exclusive  of  East  Fork  it  embraces  about  6,000  square  miles.  The  East 
Fork  enters  the  district  covered  by  the  Illinois  lobe  only  in  the  portion 
below  the  bend  west  of  Shoals,  and  therefore  lies  mainly  outside  the  field 
of  the  present  discussion,  which  is  restricted  to  the  lower  course  of  the 
main  White  River. 

Near  Mai-tinsville,  in  southern  Morgan  County,  White  River  leaves 
the  disti'ict  which  has  been  covered  by  more  eastern  portions  of  the  ice 
sheet,  and  from  this  point  to  its  mouth,  a  distance  of  125  miles  by  direct 
line,  lies  within  the  limits  of  the  district  covered  by  the  Illinois  lobe.  That 
lobe  encroached  only  a  few  miles  upon  territory  east  of  White  River,  the 
greatest  known  extension  being  about  20  miles,  at  points  where  it  touches 
upon  East  White  Valley  east  and  south  of  Loogootee  in  western  Martin 
County.  Throughout  much  of  the  distance  below  Martinsville  the  glacial 
boundary  is  within  10  miles  east  of  the  east  bluff  of  the  present  river. 

The  valley  of  White  River  for  a  few  miles  below  Martinsville,  although 
including  sections  of  a  preglacial  line  or  lines,  has  not  been  definitely  con- 
nected with  the  preglacial  line  occupied  by  the  stream  in  its  lower  course. 
The  river  crosses  a  rock  ridge  just  below  Ramona,  another  just  above 
Spencer,  while  below  Spencer  it  flows  for  a  few  miles  in  a  narrow  .shallow 
channel  among  hills  and  ridges,  there  being  apparently  no  definite  pre- 
glacial di-ainage  line  to  control  its  coui'se.  It  occupies  a  preglacial  valley 
from  the  mouth  of  Raccoon  Creek  down  to  Worthington,  having  a  width  of 
nearly  a  mile.  Near  Worthington  the  valley  joins  a  larger  preglacial  val- 
ley, 2   to  2.J   miles  wide,  wliicli  Iciids  in   from  the   north    along  the  lower 


WABASH  EIVER  DRAINAGE  BASIN.  533 

course  of  Eel  River.  From  this  point  to  its  mouth  the  course  of  the  stream 
is  nearly  coincident  with  a  broad  preglacial  line. 

At  Worthington  there  is  a  minor  stream  deflection.  The  preglacial 
valley  of  Eel  River  leads  southward,  while  the  present  sti'e'am  passes  east- 
ward into  White  River  through  a  gap  in  a  line  of  hills  that  continues  south 
a  few  miles  in  the  midst  of  the  broad  valley  of  White  River.  It  is  probable 
that  this  line  of  hills  is  the  remnant  of  a  narrow  ridge  separating  the  pre- 
glacial Eel  River  Valley  from  the  smaller  preglacial  valley  coming  in  from 
the  northeast. 

Below  the  junction  of  these  two  valleys  White  River  has  a  valley  of 
irregular  width,  ranging  from  3  miles  to  fully  twice  that  width.  Broad  low 
tracts  extend  up  tributaries  several  miles.  They  are  conspicuous  on  the 
west  side,  in  both  Greene  and  Knox  counties,  but  on  the  east  side  they  first 
become  conspicuous  in  Daviess  County  south  of  Greene.  These  lowlands 
are  deeply  filled  with  drift  and  appear  to  be  the  lines  occupied  by  preglacial 
tributaries.     They  are  now  mainly  occupied  by  very  small  creeks. 

Attention  has  already  been  called  to  some  interesting  deflections  of 
eastern  tributaries  of  White  River  in  Owen  and  Greene  counties,  Indiana, 
evidently  caused  by  the  pi'esence  of  the  ice  sheet,  deflections  which  were 
discovered  by  Mr.  C.  E.  Siebenthal,  of  the  Indiana  survey.  Other  deflec- 
tions, also  discovered  by  Siebenthal,  appear  to  be  referable  in  great  part  to 
drift  filling,  occurring  as  they  do  within  the  limits  of  glaciation.  Thus 
Raccoon  Creek  makes  a  slight  detour  into  its  old  south  blufi"  IJ  to  2  miles 
below  Freeman,  its  former  course  being  indicated  by  a  slight  sag  or  depres- 
sion lying  north  of  the  present  stream.  A  similar  though  somewhat  greater 
departure  is  made  by  Richland  Creek  near  Tulip,  about  6  miles  above  its 
mouth.  A  deflection  of  a  difi'erent  class  was  iloted  by  Siebenthal  in  the 
basin  of  McCormack's  Creek  east  of  Spencer.  This  basin  apparently  had 
subterranean  drainage  prior  to  the  ice  invasion,  but  was  compelled  to  make 
a  surface  channel  after  the  drift  deposition.-'  The  creek  has  falls  which 
have  cut  back  a  gorge  in  limestone  about  1  mile  from  White  River.  The 
gorge  is  smaller  and  the  stage  of  development  less  advanced  than  in  gorges 
OD  .similar-sized  streams  of  northwestern  Illinois.  But  as  the  rock  is  some- 
what harder  than  that  bordering  the  gorges  of  northwestern  Illinois,  no 
great  diff'erence  in  age  need  be  inferred. 

'  See  TTvent,v-lir.st  Aim.  Rept.  Indiana  Ceol.  Surs-ey,  1896,  pp.  301,  302. 


534  THE  ILLINOIS  GLACIAL  LOBE. 

The  drift  has  sufficient  thickness  on  the  west  side  of  White  River  to 
render  the  tracing  of  preglacial  drainage  lines  difficult  if  not  impracticable. 
A  smooth  drift  plain  extends  west  from  the  bend  of  Eel  River  in  south- 
western Clay  County  to  the  Wabash  Valley  in  Vigo  and  Sullivan  counties, 
in  which  preglacial  lines  are  almost  entirely  concealed.  The  preglacial 
divide  was  probably  far  from  coincident  with  the  present  dixnde.  In  more 
elevated  districts  east  of  the  bend  the  drift  is  in  places  filled  to.  the  level  of 
the  high  rock  ridges,  completely  disguising  some  of  the  lines  of  connection. 
For  example,  just  north  of  the  town  of  Spencer  a  preglacial  valley  connects 
with  White  River,  which,  within  a  mile  to  the  north,  becomes  traceable 
onlv  by  means  of  well  records,  there  being  no  depression  between  rock 
ridges  to  indicate  its  course.  This  is  thoug'ht  to  lead  through  to  Mill  Creek, 
connecting  with  its  valley  just  above  the  falls  at  Cataract.  But  whether 
formed  by  a  stream  flowing  northward  or  in  the  reverse  direction  is  not 
known. 

EMBARRAS   RIVER. 

This  western  tributary  of  Wabash  River  drains  an  area  of  about 
2,000  square  miles  in  eastern  Illinois.  Its  source  is  in  the  Champaign 
morainic  system,  immediately  south  of  the  city  of  Champaign.  For  about 
20  miles  it  flows  between  the  outer  and  main  ridge  of  the  Champaign  system, 
but  passes  tlu-ongh  the  outer  ridge  in  northern  Douglas  County.  It  then 
bears  southeast  for  about  10  miles  to  a  small  till  ridge,  correlated  with  the 
Cerro  Gordo  moraine,  which  it  crosses  in  southeastern  Douglas  County. 
The  course  is  then  slightly  west  of  south  for  25  miles,  at  which  point  it 
leaves  the  Shelljysnille  or  earliest  Wisconsin  sheet  of  drift.  It  continues 
southward  25  or  30  miles  farther  to  the  vicinity  of  Newton,  where  it 
chano-es  to  a  southeastward  course  and  maintains  this  course  to  its  mouth, 
a  distance  of  50  miles. 

The  portion  lying  within  the  limits  of  the  Wisconsin  drift  di-ains  a 
naiTOw  strip  and  has  a  very  small  channel.  Upon  emerging  from  that  drift 
it  at  once  enters  a  nnich  broader  valley,  which  appears  to  have  been  exca- 
vated nearly  to  its  present  dimensions  prior  to  the  Wisconsin  stage  of 
glaciation,  for  the  valley  gravels  connected  with  the  Shelbyville  moraine 
lead  down  the  river  bottom  in  sucli  manner  as  to  indicate  the  existence  of 
the  valley  at  the  time  of  their  deposition.  Upon  following  the  valley  down, 
its  width  increases  from  less  than  a  mile  at  the  border  of  the  Shelbyville 


WABASH  RIVEE  DRAINAGE  BASIN.  535 

moraine  to  about  2  miles  at  Newton,  and  to  3  or  4  miles  in  the  lower  course 
of  the  stream.  The  portion  below  Newton  has  its  course  determined  largely 
by  a  preglacial  line  of  drainage,  and  possibly  the  preglacial  line  extends  up 
the  valley  as  far  as  the  vicinity  of  Greenup,  18  miles  above  Newton.  This 
upper  portion,  however,  may  prove  to  have  been  entirely  excavated  in  an 
interglacial  stage. 

The  Embarras  River  has  but  one  large  tributary — Hickory  Creek — 
which  heads  in  the  Shelby ville  moraine  in  southern  Edgar  County  and 
leads  southward  across  western  Clark  and  eastern  Jasper  counties,  a  distance 
of  over  40  miles,  entering  the  Embarras  about  10  miles  below  Newton. 
The  course  of  this  stream  is  probably  nearly  coincident  with  the  preglacial 
line  in  its  lower  20  miles,  and  possibly  the  upper  portion  is  determined  by 
a  preglacial  line.  At  least  the  drift  is  somewhat  thicker  along  the  borders 
of  the  stream  than  on  neighboring  districts  to  the  east  and  west,  while  the 
altitude  is  somewhat  lower. 

BUSSEKON   CREEK. 

This  small  eastern  tributary  of  the  Wabash  has  its  source  on  the  clay 
plain  at  the  borders  of  Clay  and  Vigo  counties,  near  the  bend  of  Eel  River, 
referred  to  above.  Its  course  is  southwestward  across  Sullivan  Count}?-  into 
the  Wabash  Valley.  For  a  few  miles  near  its  mouth  the  stream  evidently 
occupies  a  preglacial  line  of  drainage,  but  its  headwater  portion  is  appar- 
ently independent  of  preglacial  drainage. 

BIG   RACCOON    CREEK. 

This  stream  with  its  main  tributary.  Little  Raccoon  Creek,  drains  an 
area  of  about  500  square  miles  in  western  Indiana,  mainly  in  Parke  County, 
but  including  portions  of  Boone,  Hendricks,  Montgomery,  and  Putnam 
counties.  Its  source  is  in  southwestern  Boone  County,  and  it  takes  a 
southwestward  course  from  this  point  to  southern  Parke  County,  a  distance 
of  fully  50  miles  by  direct  line,  being  mainly  independent  of  preglacial 
lines.  It  there  enters  a  channel  which  formerly  carried  a  part  of  the 
drainage  into  Wabash  River,  and  follows  this  channel  northward  about 
15  miles  before  entering  the  Wabash.  Little  Raccoon  Creek  joins  Big- 
Raccoon  at  the  point  where  this  old  channel  of  the  Wabash  is  entered,  and 
apparently  follows  a  preglacial  valley  in  its  lower  course.  The  northward 
deflection  of  the  Big  Raccoon  has  probably  resulted  from  a  silting  up  of 


536  THE  ILLINOIS  GLACIAL  LOBE. 

the  south  end  of  the  old  Wabasli  Baj-ou  by  tlie  sediments  brought  down 
by  the  creek,  for  it  seems  probable  that  the  creek  continued  southwestward 
into  the  Wabash  along-  the  soiith  end  of  the  channel  opened  by  that  stream 
for  some  time  after  the  abandonment  of  the  channel  by  the  river.  The 
abrupt  change  in  the  rate  of  fall  would  naturally  produce  an  accumulation 
of  silt  at  the  point  where  it  entered  the  old  bayou  of  the  Wabash,  and  this 
may  have  resulted  in  the  deflection  of  the  stream  northward  through  an 
unfilled  portion  of  the  bayou.  The  watershed  of  Big  Racdoon  and  Little 
Raccoon  creeks  lies  mainl}'  within  the  Wisconsin  drift,  but  in  southern 
Parke  County  it  lies  outside  that  drift. 

SUGAR   CREEK. 

Sugar  Creek,  another  eastern  ti-ibutary  of  the  Wabash,  enters  the  river 
about  8  miles  above  the  mouth  of  Big  Raccoon  Creek.  It  drains  an  area 
of  perhaps  900  square  miles,  embracing  southern  Clinton,  northern  Boone, 
central  ]Montgomery,  southeastern  Fountain,  and  northern  Parke  counties. 
Its  length  is  about  80  miles  by  direct  course,  but  the  width  of  the  water- 
shed scarcely  reaches  25  miles  at  any  point,  and  the  average  width  is  not 
more  than  12  miles. 

This  stream  lies  wholly  within  the  limits  of  the  Wisconsin  drift,  and, 
with  the  possible  exception  of  a  few  miles  near  its  mouth,  has  a  course 
independent  of  preglacial  lines.  Its  rock  gorges,  which  set  in  a  few  miles 
below  Crawfordsville,  afford  some  of  the  most  picturesque  scenery  in  the 
State.  Above  Crawfords%alle  the  stream  has  a  shallow  channel  which 
touches  the  rock  at  only  a  few  points.  At  the  headwaters  the  drift  is 
shown  by  deep  wells  to  have  a  thickness  of  250  to  300  feet.  At  Craw- 
fordsville a  preglacial  valley  is  crossed  whose  rock  floor  is  more  than  100 
feet  below  the  present  stream. 

This  stream  cuts  through  a  moraine  of  the  Champaign  system  in 
southwestern  Montgomerj-  County,  below  which  point  it  crosses  a  plain 
lying  north  of  the  moraine.  The  headwater  portion  above  Crawfordsville 
lies  within  the  limits  of  the  Erie  Cxlacial  Lobe. 

VERMILION   RIVER. 

This  western  tributary  of  the  Wabash  drains  about  1,500  square  miles 
in  eastern  Illinois.  Its  lower  course  for  a  distance  of  about  10  miles  lies 
within  the  State  of  Indiana,  but  it  there  drains  only  the  immediate  borders 


WABASH  RIVER  DRAINAGE  BASIN.  537 

of  the  valley.  The  headwaters  are  in  the  midst  of  the  Bloomington 
morainic  system  at  the  reentrant  angle  in  Ford  and  Livingston  counties, 
Illinois,  a,nd  only  a  few  miles  from  the  headwaters  of  a  stream  of  the  same 
name  flowing  to  the  Illinois.  To  distinguish  it  from  that  stream  the  name 
Wabash- Vermilion  has  come  into  use. 

The  middle  or  main  fork  has  a  southward  course  for  a  few  miles  from 
its  source,  between  two  ridges  of  the  Bloomington  system  in  Ford  County, 
locally  known  as  the  Roberts  and  Melvin  ridges.  It  then  passes  through 
Melvin  Ridge  and  receives  a  tributary  draining  a  sag  or  narrow  plain  lying 
between  that  ridge  and  the  outer  moraine  of  the  Bloomington  systen^i.  It 
takes  a  southeastward  course  through  this  narrow  plain  across  southeastern 
Ford,  northeastern  Champaign,  and  western  Vermilion  counties,  to  the 
village  of  Potomac.  There  it  turns  abruptly  southward  and  passes  through 
the  outer  ridge  of  the  Bloomington  system.  Upon  emerging-  from  this 
moraine  it  receives  West  or  Salt  Fork,  which  drains  a  plain  in  eastern 
Champaign  and  western  Vermilion  counties  lying  between  the  Bloomington 
and  Champaign  morainic  systems.  The  united  stream  flows  east  about  6 
miles  to  the  city  of  Danville,  where  North  Fork  leads  in  from  the  north. 
That  fork  drains  only  a  small  area  .among  the  ridges  of  the  Bloomington 
system  in  eastern  Vermilion  County,  Illinois,  and  adjacent  parts  of  Indiana. 
From  the  city  of  Danville  the  stream  leads  southeastward  through  a  till 
plain  to  the  Wabash  Valley.  In  this  portion  it  treiiches  considerably  into 
the  rock,  but  above  the  immediate  vicinity  of  Danville,  so  far  as  known  to 
the  writer,  no  rock  is  encountered  by  any  of  the  streams. 

The  entire  drainage  system  is  independent  of  preglacial  lines,  for  the 
drift  has  built  up  the  surface  above  the  level  of  the  rock  divides.  A  boring 
at  Danville  Junction,  Illinois,  and  one  near  Eugene,  Indiana,  each  strike 
into  a  preglacial  valley  in  which  rock  is  first  encountered  at'  a  level  100 
feet  or  more  lower  than  rock  ledges  in  that  -^dcinity  which  have  been  cut 
into  by  the  present  stream  in  deepening-  its  valley.  There  is  no  surface 
indication  of  the  course  of  the  preglacial  drainage,  but  it  may  be  inferred 
that  it  passed  from  the  points  named  into  the  preglacial  valley  occupied  by 
the  Wabash.  The  Vermillion  also  crosses  a  preglacial  valle}^  a  few  miles 
below  Danville.  Its  bottom  there  spreads  out  to  a  width  of  more  than  a 
mile,  or  to  more  than  twice  its  usual  width.  This  feature  is  well  shown  on 
the  Danville  topographic  sheet. 


538  THE  ILLINOIS  GLACIAL  LOBE, 

r,AKE    MICHIGAX    DRAINAGE    BASIN. 

Lake  ^Michigan  receives  the  drainage  of  only  a  very  narrow  belt  in 
northeastern  Illinois  and  northwestern  Indiana,  comprised  mainly  in  the 
di'ainage  areas  of  Chicago  and  Calumet  rivers.  It  drains  about  one-half 
the  area  of  the  southern  peninsula  of  Michigan  and  1,500  square  miles  of 
the  northeast  jjart  of  Indiana.  It  drains  also  an  area  of  several  thousand 
square  miles  in  the  noi'thern  peninsula  of  Michigan  and  adjacent  portions 
of  Wisconsin,  mainly  tributary  to  Green  Bay.  South  of  the  Green  Bay 
drainage  system  only  a  narrow  belt  is  tributary  to  the  lake.  The  water- 
shed draining  to  Lake  Michigan  is  estimated  to  be  45,000  square  miles, 
and  the  total  area  of  the  basin  68,100  square  miles,  the  lake  area  being 
22,400  square  miles.^ 

In  the  present  discussion  only  that  portion  of  the  watershed  is  con- 
sidered which  borders  the  southern  end  of  the  Lake  Michig-an  Basin  and 
lies  within  the  limits  of  the  Illinois  glacial  lobe. 

CHICAGO    RIVER. 

With  the  exception  of  a  few  miles  at  the  headwaters  of  the  North 
Fork,  this  small  drainage  system  lies  within  the  limits  of  Lake  Chicago. 
The  South  Fork,  as  previously  noted,  apparently  has  afforded  a  line  of 
discharge  for  the  Des  Plaines  River  from  the  time  of  the  withdrawal  of  the 
lake  down  nearly  to  historic  times,  the  size  and  depth  of  its  channel  being 
such  as  would  seem  to  demand  the  work  of  a  stream  as  large  as  the  Des 
Plaines.  The  southward  course  of  the  North  Fork,  outside  the  limits  of 
the  lake  bottom,  is  occasioned  by  till  ridges  of  the  Lake  Border  morainic 
system,  the  one  on  the  east  preventing  direct  discharge  into  Lake  Michigan. 
Within  the  limits  of  Lake  Chicago  the  stream  follows  the  slope  of  the  old 
lake  bottom. 

OALUMET   RIVER. 

The  headwaters  of  the  Calumet  River  are  in  the  Valparaiso  morainic 
system  south  of  Michigan  City,  Indiana.  Its  several  southern  tributaries 
are  also  found  in  the  inner  slope  of  the  Valparaiso  morainic  system.  These 
tributaries  lead  down  the  slope  to  the  plain  covered  by  Lake  Chicago. 
Their  courses  are  there  controlled  to  some  extent  by  the  line  of  sand  dunes 

'  Rept.  U.  S.  Deep  Waterways  Commission,  1896,  p.  149. 


LAKE  MICHIGAN  DEAINAGE  BASIN.  539 

formed  along  the  beaches  of  the  old  lake,  and  to  a  slight  extent  by  till 
ridges,  as  in  the  case  of  the  portion  of  Calumet  River  in  Porter  County, 
Indiana.  This  stream  now  has  its  mouth  at  South  Chicago,  in  Illinois,  but 
a  former  channel  carried  its  discharge  eastward  to  the  head  of  Lake  Michi- 
gan in  northeastern  Lake  County,  Indiana.  There  is  a  tradition  that  the 
change  to  the  present  course  was  brought  about  by  dragging  canoes  across 
the  low  portage  between  Calumet  Hiver  and  Calumet  Lake. 

TRAIL   CEEEK. 

This  small  tributary  of  Lake  Michigan  entering  at  Michigan  City, 
Indiana,  owes  its  peculiar  T-shaped  drainage  to  the  presence  of  a  till  ridge. 
The  arms  of  the  T  are  formed  by  streams  flowing  on  the  outer  or  south 
border  of  the  ridge,  which  upon  meeting  pass  through  it  and  take  a  more 
direct  course  toward  Lake  Michigan. 

GALIEN    RIVER. 

The  Gralien  River  drainage  system  consists  of  two  rivers.  North  Gralien 
and  South  Gralien,  which  unite  about  5  miles  from  the  point  where  the 
stream  enters  Lake  Michigan,  at  New  Buifalo,  Michigan.  The  South  Fork 
has  two  branches,  one  of  which,  like  the  branches  of  Trail  Creek,  has  a 
course  nearly  parallel  with  the  shore  of  Lake  Michigan,  caused  by  the 
same  till  ridge  which  governs  the  course  of  the  headwater  portion  of  Trail 
Creek.  The  other  branch  of  the  South  Fork  heads  in  the  Valparaiso 
morainic  system  and  takes  a  general  northwestward  course  toward  the  lake. 

The  North  Galien  River  has  several  headwater  tributaries  leading- 
down  from  the  Valparaiso  morainic  system  and  uniting  just  outside  the 
outer  till  ridge  of  the  Lake  Border  system.  Upon  passing  through  this 
ridge  the  stream  turns  southwestward  along  a  sag  or  nai-row  plain  lying 
between  Outer  and  Covert  ridges.  Upon  joining  the  South  Galien  River 
the  united  stream  passes  through  Covert  Ridge  and  soon  enters  Lake 
Michigan. 

ST.  JOSEPH   EIVER. 

This  large  eastern  tributary  of  Lake  Michigan  has  a  drainage  area  of 
about  4,000  square  miles,  exclusive  of  Pawpaw  River,  which  joins  it  within 
a  mile  of  its  mouth.  Of  this  drainage  area  3,550  square  miles  lie  above 
South  Bend,  Indiana,  the  point  where  the  St.  Joseph  formerly  connected 


540  THE  ILLINOIS  GLACIAL  LOBE. 

witli  the  Kankakee.  It  is  oulv  the  portion  below  South  Bend  wliich  falls 
within  the  limits  of  tlie  present  discussion. 

Between  South  Bend  and  Niles  the  St.  Joseph  River  has  its  course 
through  a  gravel  plain  that  lies  outside  the  Valparaiso  morainic  system. 
This  gravel  plain  is  connected  on  the  south  with  the  Kankakee  g-ravel-and- 
sand  area.  The  gravel  plain  also  continues  northeastward  from  Niles  up 
the  Dowagiac  Valley  nearly  to  the  source  of  that  stream.  Just  below  Niles 
the  St.  Joseph  River  turns  westward  around  the  north  end  of  a  sharp 
moraine  which  apparently  pertains  to  the  Saginaw  lobe  (see  PI.  XV),  but 
at  the  village  of  Buchanan  it  leaves  that  moraine  and  enters  the  Valparaiso 
morainic  system.  It  emerges  from  the  Valparaiso  system  about  15  miles 
below  Buchanan.  Its  course  is  then  northwestward  into  Lake  Michigan, 
with  only  slight  deflections  in  passing  the  two  till  ridges  which  lie  between 
the  Valparaiso  system  and  the  lake. 

Hickory  Creek,  a  southern  tributary  entering  the  St.  Joseph  about  6 
miles  above  its  mouth,  takes  a  direct  course  from  the  Valparaiso  morainic 
sjT^stem  northwestward  through  the  outer  till  ridge,  but  is  prevented  from 
passing-  directly  into  the  lake  by  Covert  Ridge;  the  creek  accordingly 
follows  the  ridge  in  a  course  east  of  north  and  discharges  into  the  St. 
Joseph  River. 

Two  eastern  tributaries  of  the  St.  Joseph  are  worthy  of  note.  Pipe- 
stone Creek,  a  small  tributary  entering  about  12  miles  above  the  mouth  of 
the  river,  drains  a  small  lowland  tract  between  two  member's  of  the  Valpa- 
raiso morainic  system,  in  eastern  Bei'rien  County.  Dowagiac  River,  which 
enters  the  St.  Joseph  at  Niles,  as  already  noted,  di-ains  a  gra^•el  plain 
h'iug  outside  the  Valparaiso  system.  An  eastern  branch  of  the  same  river 
drains  a  lowland  tract  between  two  Saginaw  moraines  in  noi'thwestern  Cass 
County,  but  breaks  tlii'oug'h  the  western  moraine  to  enter  Dowagiac  River 
iiear  Dowagiac. 


PAWPAW    RIVER. 


Pawpaw  River  has  its  headwaters  in  swampy  plains  lying  east  of 
the  limits  of  the  Valparaiso  morainic  system  (see  PI.  X\').  The  several 
headwater  .streams  unite  liefore  reaching  the  Valparaiso  system.  The 
stream  then  passes  westward  in  a  somewhat  winding  course  nmong  its  ridges 
and  hills,  emero-ino-  from  it  near  Hartford,  but  t'ollowiny  its  inner  border 
nearly  to  its  junction  witli  St.  Joseph  Ri\('i-.     No  important  tributaries  are 


LAKE  MICHIGAN  DRAINAGE  BASIN.  541 

received  after  the  stream  enters  the  Valparaiso  system,  and  it  di-ains  only 
a  narrow  strip  scarcely  6  miles  in  average  width.  As  above  noted;  it  enters 
the  St.  Joseph  River  within  a  mile  of  the  lake,  and  the  two  drainage  systems 
are,  therefore,  nearly  distinct. 

BLACK   RIVER. 

Three  nearly  distinct  drainage  systems,  known  as  North,  Middle,  and 
South  Black  rivers,  drain  a  district  in  southwestern  Allegan  and  northwest- 
ern Van  Buren  counties  lying  west  of  the  Valparaiso  morainic  system. 
They  unite  before  passing  through  Covert  Ridge,  and  the  united  stream 
enters  the  lake  at  South  Haven.  The  north  branch  leads  westward  from 
the  "Pine  Plains"  to  Covert  Ridge,  and  there  is  deflected  southward.  Mid- 
dle branch  takes  a  nearly  direct  westward  course  from  the  "Pine  Plains"  to 
its  junction  with  the  north  branch.  The  south  branch  is  deflected  north- 
ward in  its  lower  course  along  the  east  border  of  Covert  Ridge. 

KALAMAZOO    RIVER. 

This  stream,  with  a  di-ainage  area  nearly  as  large  as  the  St.  Joseph 
River,  has  been  deflected  at  several  points  by  morainic  ridges  formed  by 
the  Saginaw  lobe,  but  the  lower  course  through  the  Valparaiso  morainic 
system  and  districts  to  the  west  is  somewhat  direct.  This  lower  course 
was  opened  after  the  ice  sheet  withdrew  from  the  Valparaiso  system.  The 
discharge  during  the  occupancy  of  this  morainic  system  was  apparently 
southward  into  the  St.  Joseph  Rives.  The  peculiar  complications  of  its 
history  can  only  be  appreciated  after  a  description  of  the  moraines  of  the 
Saginaw  lobe.     This  will  appear  in  a  separate  report  now  in  preparation. 

The  Kalamazoo  River  receives  only  one  important  tributaiy  in  the 
district  west  from  the  Valparaiso  morainic  system.  This  tributary — Rapid 
River — drains  a  narrow  belt  in  the  northern  part  of  Allegan  County, 
extending  from  the  east  border  of  the  Valparaiso  system  westward  through 
the  inner  members  of  that  system  and  across  the  "Pine  Plains"  to  the 
outer  border  of  Covert  Ridge,  where  it  unites  with  the  Kalamazoo  River 
(see  PI.  XV). 


CHAPTER   XIII. 
AVERAGE   THICKNESS   OF  THE    DRIFT   IN   ILLINOIS. 

The  region  under  discussion  is  one  which  may  perhaps  furnish  a  more 
complete  series  of  data  concerning  the  thickness  of  the  drift  than  any  region 
of  equal  size  yet  studied.  It  is  especially  favorable,  not  onlr  because  of 
the  large  number  of  sections  of  boi'ings  obtained,  but  also  because  of  the 
comparative  smoothness  of  the  region,  an  estimate  of  average  thickness 
being  more  readily  obtained  in  a  comparatively  plane  region  than  in  a  very 
hilly  one. 

The  inequalities  of  the  rock  surface,  as  indicated  above,  are  sufficient  to 
give  the  drift  considerable  A^ariation  in  thickness,  for  in  much  of  the  region 
the  amount  of  drift  is  sufficient  to  fill  the  valleys  or  basins  nearly  to  a  level 
with  the  uplands,  only  the  most  prominent  parts  of  the  uplands  rising  above 
the  general  level  of  the  drift  surface. 

The  thickness  of  the  drift  also  varies  because  of  aggregation  in 
morainic  ridges,  there  being  several  prominent  morainic  belts  in  which  the 
thickness  is  as  much  greater  than  that  of  the  bordering  plains  as  the  measure 
of  the  relief  of  the  moraines.  The  inequalities  in  thickness  resulting  from 
morainic  accumulations  are,  however,  much  less  than  those  resulting 
fi'om  variations  in  the  altitude  of  the  underljnng  rock,  being  seldom  greater 
than  100  feet  and  often  but  40  to  50  feet,  while  variations  due  to  inequalities 
of  the  rock  surface  often  reach  200  feet  and  may  in  places  exceed  300  feet. 

In  a  general  sense  it  is  true  that  in  the  portions  of  this  region  where 
but  a  single  ice  invasion  has  occurred  the  di-ift  is  thinner  than  where  there 
has  been  a  succession  of  invasions.  Thus  the  southeastern,  southern, 
and  western  jjortions  show  thinner  deposits  of  drift  than  the  central  and 
northeastei'n.  Yet  extensive  ai-eas  of  comparatively  thin  drift  occur  in 
the  norfheastern  portion  on  the  borders  of  the  Kankakee  River  and  in  the 
vicinity  of  the  Chicago  Outlet,  i.  e.,  in  places  where  the  number  of  invasions 
has  been  greatest. 

542 


AVERAGE  THICKNESS  OF  THE  DEIFT  IN  ILLINOIS.  543 

There  are  two  quite  different  methods  by  which  the  thickness  of  the 
drift  may  be  estimated.  The  first  is  that  employed  some  years  ago  by 
Chamberlin  and  Salisbury,  which  is  based  upon  a  comparison  of  the 
Driftless  Area  of  southwestern  Wisconsin  with  drift-covered  areas  on  its 
borders.^  The  second  is  based  upon  wells  or  other  borings  and  upon  rock 
outcrops  within  the  drift-covered  areas.  By  either  method  only  a  rude 
approximation  can  be  expected.  In  comparing  drift-covered  areas  with  the 
Driftless  Area  by  the  first  method,  some  allowance  must  be  made  for  depar- 
tures within  the  drift-covered  areas,  from  the  type  or  types  of  topography 
exhibited  in  the  Driftless  Area.  A  region  underlaid  by  shale  is  likely  to 
have  a  topography  somewhat  diff'erent  fi'om  one  underlaid  by  limestone  or 
sandstone,  while  among  the  several  classes  of  limestone  and  sandstone  much 
variation  in  topography  may  be  found.  To  make  discriminative  estimates 
it  is  necessary  to  have  a  fair  acquaintance  with  the  several  types  of  topog- 
raphy likely  to  be  encountered  within  a  given  drift-covered  area,  as  well  as 
with  the  types  found  in  the  Driftless  Area.  Such  an  estimate  will  also  be 
made  more  reliable  throiigh  an  acquaintance  with  the  distribution  of  the 
main  preglacial  lines  of  drainage  in  the  drift-covered  area  under  investiga- 
tion and  the  extent  of  each  preglacial  watershed.  In  an  estimate  based 
upon  borings  and  outcrops  there  is  room  for  much  error,  since  they  may 
inadequately  test  the  thickness  of  the  drift.  Indeed,  it  is  to  be  expected 
that  there  will  be  a  larger  number  of  outcrops  and  a  greater  jjroportion  of 
borings  which  reach  rock  along  the  line  of  the  preglacial  ridges  than  along 
the  preglacial  valleys,  especially  where  the  drift  has  filled  the  valleys  to  the 
level  of  the  ridges.  By  employing  both  methods  the  results  are  more  likely 
to  be  reliable  than  by  either  method  alone.  The  borings  throw  some  light 
upon  the  preglacial  topography  and  thus  help  in  an  estimate  in  which  pre- 
glacial topography  is  made  the  main  basis  of  calculation;  while  in  an  estimate 
based  largely  upon  borings  and  outcrops  a  knowledge  of  the  topograph}^  of 
neighboring  driftless  tracts  is  of  great  value.  The  data  from  well  borings 
and  the  results  of  estimates  based  upon  them  are  first  presented.  These 
results  are  then  considered  in  the  light  of  an  estimate  based  upon  the 
requirements  of  the  topography. 

The  thickness  of  the  drift  has  been  ascertained  at  1,339  points  within  the 
district  covered  by  the  Illinois  lobe,  of  which  1,179  are  within  the  State  of 


'  See  Sixth  Auu.  Rept.  U.  S.  Geol.  Survey,  1884-85,  p[).  257-258. 


544  THE  ILLINOIS  GLACIAL  LOBE. 

Illinois.  The  estimates  of  average  thickness  are  restricted  to  Illinois,  inas- 
much as  the  data  collected  there  are  fuller  than  in  portions  of  neighboring 
States  covered  by  the  Illinois  lobe.  It  is  also  a  geographic  unit  to  which 
the  addition  of  the  neighboring  districts  would  be  of  no  advantage.  Fur- 
thermore, the  amount  of  drift  in  these  neighboring  districts  apparently  differs 
so  little  from  that  of  the  adjacent  portions  of  Illinois  that  the  result  would 
not  be  materially  affected  by  including  them  in  the  calculation.  The 
greater  part  of  the  borings  upon  which  these  computations  are  based  are 
presented  in  the  detailed  discussion  of  wells  below,  while  their  relative  fre- 
quency is  shown  in  the  accompanying  map  (PI.  XX). 

If  the  points  at  which  the  thickness  of  di'ift  has  been  determined  were 
distributed  uniformly  over  the  region,  it  would  be  an  easy  matter  to  ascer- 
tain the  average  thickness,  but  it  so  happens  that  in  some  parts  of  the  region 
the  thickness  has  been  tested  at  much  more  frequent  intervals  than  at  other 
parts.  This  necessitates  a  discriminative  averaging,  by  which  a  district 
having  many  borings  shall  not  be  made  of  undue  importance  in  determin- 
ing the  average  for  the  State.  For  example,  254  of  the  1,179  borings  are 
found  in  five  counties  of  northeastern  Illinois,  bordering  the  Kankakee  River 
and  Chicago  Outlet,  and  represent  an  average  area  of  only  1 6  square  miles 
for  each  boring,  while  the  average  for  the  State  is  45  square  miles  for  each 
boring.  In  the  remaining  area  occupied  by  the  Wisconsin  drift,  there  are 
only  233  borings  and  each  boring  represents  an  average  area  of  61i^  square 
miles.  In  the  portion  outside  the  Wisconsin  drift,  the  district  north  of 
Green  River  Basin  has  one  boring  for  every  36  square  miles;  that  south 
of  Grreen  River  Basin  one  boring  for  76.2  square  miles;  that  between  the 
Illinois  and  Kaskaskia  one  boring  for  61.1  square  miles,  and  that  east  of 
the  Kaskaskia  one  boring  for  78  square  miles.  In  view  of  these  differences 
it  was  decided  to  make  an  average  of  townships  since  they  have  uniform 
areas.  This  was  done  by  averaging  the  wells  entering  rock  in  each  town- 
ship and  dividing  the  sura  of  the  averages  for  each  township  by  the  number 
of  townships  in  which  rock  is  sti-uck.  This  method  seems  preferable  to  au 
average  by  counties  (which  was  the  first  method  attempted),  since  it  is  an 
average  of  small  areas  of  uniform  size  and  includes  only  the  townships  in 
which  rock  has  been  struck.  It  is  found  that  644  townships  are  represented 
out  of  a  total  of  1,474  townships  in  the  glaciated  portion  of  the  State,  and 


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AVERAGE  THICKNESS  OF  THE  DRIFT  IN  ILLINOIS.  545 

the  average  thickness  for  each  township  is  77.9  feet.  In  making-  the  esti- 
mates care  has  been  taken  to  avoid  dupUcations ;  thus  where  several  borings 
have  been  made  on  a  single  square  mile  which  differ  very  little  in  distance 
to  rock  they  are  considered  as  one  boring.  If,  however,  borings  in  close 
proximity  show  a  wide  difference,  they  are  each  included  in  the  computation. 

After  avei'aging  the  drift  by  townships  the  question  was  considered 
whether  the  townships  in  which  rock  has  been  struck  fairly  represent  the 
thickness  of  the  drift.  This  involved  the  consideration  of  their  distribution 
in  reference  to  moraines  and  in  reference  to  preglacial  valleys,  both  being- 
lines  where  the  drift  has  exceptional  thickness.  It  was  found  that  the 
moraines  have  been  about  as  thoroughly  tested  as  the  tracts  of  thinner  drift 
separating  them,  but  an  examination  into  the  distribution  along  preglacial 
valleys  has  led  to  the  conclusion  that  they  are  not  adequately  represented. 
Of  the  1,179  borings  which  reach  rock,  1,065,  or  fully  90  per  cent,  enter  it 
near  the  level  of  the  preglacial  uplands,  while  only  114,  or  scarcely  10  per 
cent,  pass  markedly  below  the  general  level  of  those  uplands  before  striking 
rock.  It  is  difficult  to  decide  upon  the  portion  of  the  surface  to  be  included 
in  the  valleys,  especially  if  their  intricate  network  of  tributaries  is  included, 
but  it  may  confidently  be  placed  at  not  less  than  30  per  cent;  possibly  it 
may  reach  50  per  cent.  Upon  computation  it  is  found  that  the  average 
depth  to  rock  of  the  borings  along  preglacial  valleys  is  172.44  feet,  while 
the  depth  of  those  on  the  uplands  is  67.87  feet.  If  the  uplands  comprise 
70  per  cent  of  the  glaciated  portion  of  Illinois  and  the  preglacial  valleys 
30  per  cent,  the  average  thickness  of  drift  will  be  99.23  feet.  If  the  uplands 
comprise  60  per  cent  and  the  valleys  40  per  cent,  the  average  will  be  109.7 
feet.  If  the  uplands  comprise  only  50  per  cent  and  the  valleys  50  per  cent, 
the  average  will  be  120.15  feet.  By  this  method  of  computation,  therefore, 
the  thickness  appears  to  be  not  less  than  99  feet,  and  it  may  be  120  feet  or 
even  more. 

The  thickness  is  on  the  whole  greater  within  the  area  covered  by  the 
Wisconsin  drift  than  in  other  portions  of  the  State.  Of  the  487  borings 
within  that  area  which  reach  rock,  the  average  drift  thickness  is  121  feet. 
Of  these  borings  only  52,  or  about  10  per  cent,  have  struck  preglacial  val- 
leys. The  borings  on  the  preglacial  uplands  enter  rock  at  an  average  depth 
of  109.7  feet,  while  those  along  preglacial  valleys  average  221  feet  to  the 

MON  xxxvui 35 


546  THE  ILLINOIS  GLACIAL  LOBE. 

rock.  Of  the  18,000  square  miles  covered  by  the  Wisconsin  drift,  there 
are  about  4,000  square  miles  in  which  the  thickness  is  much  below  the 
average.  This  comparatively  thin  drift  is  found  in  five  counties  which 
border  the  Kankakee  River  and  the  Chicago  Outlet,  viz,  Kankakee,  Cook, 
Will,  Grundy,  and  Lasalle  counties.  There  are  254  borings  in  these 
counties  which  enter  rock  at  an  average  depth  of  only  68.8  feet.  Of  these 
243  are  on  preglacial  uplands  and  enter  rock  at  an  average  depth  of  only 
63.8  feet,  while  11  along  preglacial  valleys  average  179  feet  to  rock. 

If  now  the  Wisconsin  drift  area  be  corrected  for  the  imperfect  repre- 
sentation of  preglacial  valleys,  in  accordance  with  the  corrections  applied 
to  the  whole  State,  it  is  found  that  the  average  thickness,  on  a  basis  of  30 
per  cent  being  in  valleys,  would  be  143  feet;  on  a  basis  of  40  per  cent  in 
valleys  the  average  will  be  154  feet,  and  on  a  basis  of  50  per  cent  in  valleys 
it  will  be  165  feet.  The  general  average  of  the  Wisconsin  drift  is  thus  40 
to  45  feet  above  that  for  the  entire  State. 

Turning  to  the  lowan  di-ift,  there  is  found  a  markedly  greater  amount 
of  drift  in  the  counties  lying  east  of  Rock  River  than  in  those  west  of  that 
stream.  The  few  borings  which  have  been  made  indicate  that  the  thickness 
in  the  former  district  will  average  not  less  than  100  feet,  while  in  the  latter 
it  is  but  50  to  75  feet.  The  thinness  of  the  lowan  drift  near  its  margin  is 
perhaps  due  in  the  main  to  the  withdrawal  of  the  loess  which  apparently 
has  been  derived  in  large  part  from  the  lowan  ice  sheet,  but  has  been 
scattered  widely  outside  the  limits  of  the  lowan  till. 

In  the  portion  of  the  State  lying  outside  the  limits  both  of  the  lowan 
and  the  Wisconsin  till  sheets — i.  e.,  the  portion  occupied  by  Illinoian  till  and 
loess — there  is  a  marked  variation  in  the  thickness  of  the  drift.  The  thinnest 
drift  of  the  State  is  found  in  the  district  lying  east  of  the  Kaskaskia,  a 
district  having  an  area  of  nearly  11,000  square  miles.  Of  the  138  borings 
reported  which  reach  rock  in  that  district,  128  are  found  on  preglacial 
uplands,  and  enter  rock  at  an  average  depth  of  only  20.4  feet.  The  10 
borings  entering  rock  along  preglacial  valleys  show  an  average  drift  thick- 
ness of  106  feet.  In  the  remainder  of  the  Illinoian  drift  area  the  boring-s 
enter  rock  at  an  average  depth  of  about  55  feet,  including  52  valley 
boxings.  The  average  thickness  on  the  preglacial  uplands  of  that  region 
scarcely  exceeds  40  feet. 


AVERAGE  THICKNESS  OF  THE  DRIFT  IN  ILLINOIS.  547 

The  following-  tabular  statement  sets,  forth  the  proportion  of  reported 
borings  between  each  100  feet  within  the  entire  district  covered  by  the  Illi- 
nois lobe,  and  includes  both  those  which  reach  rock  and  those  which  do  not. 

Knmber. 

With  400  feet  or  more 4 

With  300  to  400  feet 18 

With  200  to  300  feet 138 

With  100  to  200  feet 698 

With  less  than  100  feet 2,251 

Total 3,109 

After  the  estimates  just  recorded  were  completed,  the  thickness  of  drift 
in  Illinois  was  computed  on  the  basis  of  the  requirements  of  the  topography, 
the  data  obtained  by  Chamberlin  and  Salisbury  in  the  Driftless  Area  ser^ang 
as  a  guide.  The  investigations  in  the  Driftless  Area  led  to  the  opinion  that 
150  to  200  feet  of  drift  is  necessary  to  fill  the  valleys  up  to  the  level  of  the 
divides,  all  the  summits  of  the  ridges  being  still  left  bare,  while  300  feet 
would  be  necessary  to  bury  the  region  as  deeply  as  in  the  heavy  drift  regions 
of  the  four  adjoining  States.^ 

Upon  turning  to  Illinois,  it  is  found  that  the  drift  in  places  has  filled  the 
valleys  completely  and  brought  the  surface  up  to  a  level  perhaps  100  feet 
or  more  above  the  summits  of  the  ridges.  In  much  more  extensive  districts 
it  has  barely  filled  the  valleys,  while  in  fully  half  the  State  it  has  fallen 
short  of  filling  the  valleys,  the  amount  in  the  different  localities  being  two- 
thirds,  one-half,  one-third,  or  one-fourth  as  great  as  is  necessary  to  com- 
pletely fill  the  valleys. 

It  is  estimated  that  there  may  be  about  4,160  square  miles  along  the 
bulky  moraines  of  the  Wisconsin  drift  in  which  the  average  thickness 
reaches  300  feet;  but  in  the  greater  part  of  the  Wisconsin  drift  area  it  can 
scarcely  exceed  200  feet,  for  the  filling  extends  but  little  above  the  level 
of  the  rock  divides.  There  is  estimated  to  be  10,975  square  miles  in  which 
the  average  thickness  may  reach  200  feet,  this  district  lies  mainly  within 
the  Wisconsin  drift  but  extends  beyond  this  drift  down  the  Illinois  Valley 
through  Mason  and  the  adjoining  portion  of  Logan  County  into  Cass 
County.  The  area  of  lowan  di'ift  in  eastern  Winnebago,  Boone,  and  neigh- 
boring portions  of  McHenry  and  Kane  counties  may  possibly  have  150 

1  Sixth  Ann.  Rept.  U.  S.  Geol.  Survey,  pp.  257-258. 


548 


THE  ILLINOIS  GLACIAL  LOBE, 


feet  of  drift,  and  so  niauy  portions  of  the  Illinoian  drift  area  in  Western 
Illinois,  for  tliey  are  bnilt  np  about  to  the  level  of  the  summits  of  the  rock 
ridg-es.  It  is  estimated  that  such  areas  embrace  only  aboiit  3,550  square 
miles.  More  than  half  the  Illinoian  drift  area,  embracing  about  19,275 
square  miles,  appears  to  have  been  filled  to  about  two-thirds  the  capacity 
of  the  preglacial  valleys  and  to  have  perhaps  100  feet  of  drift.  There  Is 
an  area  of  nearly  7,000  square  miles  lying  mainly  in  southern  Illinois  but 
embracing  also  portions  of  Stevenson,  Winnebago,  Ogle,  Carroll,  and  Jo 
Daviess  counties,  in  northwestern  Illinois,  where  the  average  thickness  can 
scarcely  reach  50  feet,  the  valleys  being  filled  only  to  one-third  or  one- 
fourth  their  full  capacity.  There  remain  about  8,000  square  miles  in 
south-central  and  southwestern  Illinois  in  which  it  is  somewhat  greater  than 
in  the  districts  just  mentioned  and  may  average  75  feet. 

Summing  up  the  above  estimates  in  a  tabular  statement  and  averaging 
the  results  for  the  State,  we  have  the  following  table: 

Distribution,  by  depths,  of  glacial  drift  in  Illinois. 


Area. 

Depth  if 
Depth  of     distrihuted 
drift.          over  entire 
State. 

1 

Square 
miles. 

4,160 
10, 975 

3,  550 
19,  275 

8,190 

6,924 

Feet. 
300 
200 
150 
100 
75 
50 

Feet. 
23.50 
41.  3.5 
10.04 
36.32 
11.57 
6.52 

53, 074 

129.  30 

The  above  computations  are  necessarily  less  exact  than  those  based 
upon  borings,  but  the  method  may  prove  helpful  in  supplementing  one 
based  entirely  on  borings.  It  is  some  satisfaction  to  find  that  the  results 
obtained  by  the  two  methods  are  not  so  widely  discordant  as  to  leave 
doubtful  the  general  average  thickness.  As  the  computation  just  made 
represents  the  maximum  estimate  of  thickness,  it  should  be  compared  with 
the  highest  of  the  corrected  estimates  from  borings.  With  this  it  is  in 
essential  agreement,  being  but  9  feet  higher.     The  average  thickness  for 


AVERAGE  THICKNESS  OF  THE  DRIFT  IN  ILLINOIS.  549 

the  State  ma)"  safel)^  be  placed  at  not  more  tliaii  130  feet  and  not  less  than 
100  feet;  probably  it  lies  not  far  from  midway  between  these  amounts,  or 
115  ieet} 

'  In  the  above  estimates  everything  which  overlies  the  rock  has  been  included,  not  only  glacial 
drift,  but  residuary  clay,  alluvium,  and  loess.  In  order  to  ascertain  the  proporlion  of  till,  a  careful 
computation  has  been  made  from  the  records  of  1,687  borings  obtained  within  the  the  area  covered  by 
the  Illinois  lobe.     These  give  the  following  results : 

Per  cent. 

Till,  including  .ill  glacial  clays 69.38 

Sand,  gravel,  and  alluvium 25.25 

Loess  and  associated  silts 4.25 

Buried  soil,  residuary  clay,  etc 1. 12 

Total 100. 00 

In  this  computation  it  is  iirobable  that  the  auiount  of  residuary  material  is  Underestimated, 
since  it  is  ouly  occasionally  recognized  in  borings. 


CHAPTER    XIV. 

WELLS   OF  ILLINOIS. 

INTRODUCTION. 

lu  the  Seveuteeutli  Annual  Report  of  this  Survey  the  writer  has  pre- 
sented a  paper  on  the  "Water  resources  of  Ulmois,"  in  which  the  wells  are 
discussed  in  a  general  manner  in  connection  with  other  water  resom-ces.  The 
data  concerning  artesian  wells  and  the  wells  affording  supplies  for  cities  and 
villages  are  tabulated  in  that  paper,  but  a  large  number  of  wells  which  do 
not  admit  of  ready  classification  were  necessarily  omitted.  The  present 
discussion  aims  to  present  all  the  reliable  records  collected  in  the  State  which 
throw  light  upon  the  formations  penetrated  and  the  character  of  the  water 
supply. 

CLASSIFICATION   OF   UNDEEGROUND   WATERS. 

The  classification  of  underground  waters  g-iven  below  seems  to  include 
the  most  important  phases  or  classes  of  subterranean  distribution  to  be  found 
in  this  region.  It  has  already  been  presented  in  nearly  its  present  form  by 
the  writer  in  the  Eighteenth  Annual  Report.  In  nearly  all  cases  it  is  not 
difficult  to  decide  from  the  description  to  which  class  a  given  well  should 
he  referred,  and  it  has  scarcely  seemed  necessary,  in  the  detailed  discussion 
which  follows,  to  group  the  wells  in  classes.  They  are  instead  taken  up  by 
counties.  However,  a  tabulated  statement  has  been  prepared  setting  forth 
the  use  made  of  the  several  classes  of  wells  a.s  sources  for  city  water  supply. 

The  following  are  the  principal  classes  of  underground  waters: 

Class  I. — Grround  water,  supplied  by  direct  percolation  of  the  rainfall 
into  the  soil  and  substrata,  and  subject  to  but  little  lateral  transmission  and 
little  hydrostatic  pressure.  The  water  level  rises  and  falls  with  the  degree 
of  saturation  by  rains. 

Class  2. — Waters  in  close  association  with  streams,  as  in  valley  bottoms, 
in  which  lateral  transmission  is  great  and  hydrostatic  pressure  is  small.      It 

.5.50 


WELLS  OF  ILLINOIS.  551 

differs  from  tlie  former  class  not  only  in  the  great  lateral  transmission,  but 
also  in  being  fed  partly  by  stream  percolation.  The  level  rises  and  falls 
with  that  of  the  neighboring  streams.  This  class  should  perhaps  include 
the  waters  of  sand  plains  and  gravel  plains  which  have  no  surface  streams 
traversing  them,  for  waters  in  such  plains  usually  have  great  lateral  trans- 
mission and  but  little  hydrostatic  pressure. 

Class  3. — Water  included  in  porous  beds  of  glacial  di-ift  or  other  non- 
indurated  formations  lying  beneath  impervious  beds  but  without  strong- 
hydrostatic  pressure.  Such  water  is  supplied  from  more  or  less  distant 
absorption  areas  and  is  less  directly  influenced  by  rainfall  than  the  preced- 
ing classes. 

Class  4. — Water  with  strong  hydrostatic  pressure  included  in  porous  beds 
of  glacial  drift  or  of  alluvium.  This  includes  two  subclasses,  viz:  («) 
Flowing  wells;  and  (b)  wells  in  which  water  rises  nearly  to  the  sm-face. 
Subclass  (a)  embraces  wells  to  which  the  name  "artesian"  is  considered 
applicable,  while  the  term  is  not  extended  to  wells  of  subclass  (b). 

Class  5. — Streams  in  caves  and  subterranean  passages  in  the  rock,  fed  by 
sink  holes  and  brooks  and  also  by  direct  percolation  from  ground  water. 

Class  6. — Rock  water  with  bxit  little  current  and  slight  hydrostatic 
pressure. 

Class  7. — Rock  water  under  strong  hydrostatic  pressure.  This  includes 
two  subclasses,  viz:  (a)  Waters  which  overflow  when  tapped;  (b)  waters 
which  rise  nearly  to  the  surface.  Subclass  (a)  embraces  wells  to  which  the 
term  "artesian"  has  long  been  applied,  and  it  seems  a  convenient  term  for  use 
if  properly  restricted,  but  its  extension  to  nonflowing  wells  tends  to  mislead 
and  confuse  those  interested  in  obtaining  a  flow  of  water.^    ' 

Discrimination  in  selection  of  records. — It  should  uot  be  Inferred  that  tlic  averap'e 
depth  of  the  wells  reported  in  the  ensuing  discussion  represents  the  average 
of  all  the  wells  that  the  region  affords.  Attention  is  directed  chiefly  to  the 
deeper  wells,  since  they  throw  more  light  than  the  shallow  ones  upon  the 
structure  of  the  formations  penetrated  and  upon  the  supplies  of  water. 
The  great  majority  of  wells  in  the  State  are  the  seep  or  ground-water  wells 
(class  1).  They  are  sunk  to  depths  of  but  10  to  20  feet.  In  seasons  when 
rainfall  is  normal  or  excessive  such  wells  supply  the  needs  of  the  residents, 

'Compare  Chamberlin,  Fifth  Ann.  Eept.  U.  S.  Geol.  Survey,  p.  131. 


552  THE  ILLINOIS  GLACIAL  LOBE. 

but  iu  seasons  when  the  rainfall  is  deficient  many  of  them  fail,  or  yield  but 
a  small  amount  of  water.  The  wells  hei-e  recorded  are  generally  those 
which  afford  a  supply  of  water  iu  seasons  of  drought  as  well  as  in  rain}' 
seasons. 

The  well  records  have  been  obtained  largely  from  the  drillers.  In 
some  cases  there  is  uncertainty  as  to  the  reliability  of  such  records,  but  as 
a  rule  the  drillers  are  sufficientlv  careful  iu  their  observations  to  wan-ant 
the  accej^tance  of  their  statements.  Records  have,  in  mau}^  cases,  been 
obtained  from  the  owners  of  the  wells,  who  were  present  during  their 
excavation  and  often  assisted  in  making  the  wells.  The  village  wells  have 
usually  been  recorded  carefullv  during  the  excavation  or  drilling,  and  thus 
have  a  value  above  those  whose  records  are  given  from  memory.  The 
writer  has  rejected  such  well  records  as  are  thought  to  be  unreliable,  and 
has  endeavored  to  reduce  errors  to  a  minimum.  It  is  thought  that  the 
records  here  presented  contain  few  serious  errors,  and  that  the  general 
exposition  of  the  subject  and  general  conditions  for  obtaining  water  are  set 
forth  with  a  fair  degree  of  accurac}'.  The  published  well  records  in  the 
Geology  of  Illinois  are  also  included  in  this  report  and  duly  accredited. 

THE    GEOLOGIC   FORMATIONS. 

Since  many  of  the  wells  enter  rock,  a  map  of  the  geologic  formations 
is  here  introduced  (PI.  XXI)  which  was  prepared  by  the  writer  to  accom- 
pany a  paper  in  the  Seventeenth  Annual  Report.  It  follows  in  the  main 
Prof.  A.  H.  Worthen's  map  of  Illinois,  published  in  1875,  to  accompany 
Vol.  VI  of  the  Geology  of  Illinois,  but  a  few  corrections  have  been  made 
in  northern  Illinois  based  upon  observations  by  Mr.  Oscar  Hershey  and  the 
writer.  The  portion  covering  western  Indiana  is  based  u^jon  Dr.  A.  J. 
Phinnev's  map  of  Indiana,  published  by  this  Survey  in  1890.'  The  lime- 
stone formations  of  the  northern  and  western  parts  of  Illinois  and  the 
sandstones  and  sandv  shales  of  the  southern  and  southeastern  parts  are 
extensively  utilized  as  a  source  for  ordinary  wells  for  household  use.  The 
limestones  are  also  a  source  for  artesian  wells  or  deep  wells  having  strong 
hydrostatic  pressure.  A  few  artesian  A^ells  obtain  water  from  the  sand- 
stones of  southern  Illinois.  In  northern  and  western  Illinois  the  St.  Peter 
and  Potsdam  sandstones  are  the  sources  of  numerous  artesian  wells.     The 


I  i;ievciitb  Ann.  Kept.  l".  S.  (i.ol.  Survey,  PI.  LXIII. 


■ruiSg     o     gi 


i    ;  ilsJ      S    5      si'Si<|  =  iiJij5i.i«iiSi5oJ<ISt|5|„i|i„tS5||=|||sS5||iSSi;E|S5|3    |f5.^  g     ;E|?i|ls?§ISp||iSJS|g||iS5s^|||>g5s|| 


WELLS  OF  ILLINOIS.  553 

Lower  Magnesian  limestone  is  also  used  for  artesian  supply.  Portions  of 
the  Coal  Measures  yield  brackish  water,  and  for  this  reason  they  have  not 
been  extensively  utilized  for  water  supply.  In  some  localities,  however,  it 
has  been  found  necessary  to  make  use  of  these  formations  because  of  no 
adequate  supply  from  the  drift  or  overlying-  rocks.  In  such  places  the 
presence  of  beds  yielding  comparatively  fresh  water  has  been  made  known. 
In  the  detailed  discussion  which  follows,  the  degree  of  development  of  the 
several  rock  formations  is  set  forth. 

ATTITUDE    OP    THE    STRATA. 

The  attitude  of  the  strata  is  very  favorable  for  producing  a  strong 
hydrostatic  pressure  in  deep  wells  throughout  much  of  the  State.  A  north- 
to-south  section  shows  a  gradual  southward  dip  of  the  formations  (see  figs. 
7  and  8),  terminated  at  the  south  by  an  axis  of  upheaval  which,  as  above 
noted,  leads  eastward  across  the  southern  end  of  the  State  from  Gt-rand 
Tower  to  Shawneetown.  The  descent  probably  amounts  to  2,500  or  3,000 
feet  in  the  350  miles  from  the  north  to  the  south  end  of  the  State.  There 
are  slight  undulations  carrying  the  strata  up  or  down  100  to  200  feet  or 
more  from  a  uniform  grade,  but  so  far  as  known  no  prominent  west-to-east 
axis  of  upheaval  crosses  the  State  north  of  the  one  just  noted,  none  adequate 
to' prevent  the  southeast  passage  of  the  water. 

East-to-west  sections  are  less  uniform  in  the  inclination  of  strata  than 
the  north-to-south  sections.  Sections  across  the  northern  part  of  the  State 
present  two  blocks  of  strata,  each  dipping  gradually  to  the  east,  sejDarated 
by  an  abrupt  fold  or  line  of  disturbance  (see  fig.  9).  At  this  fold  the 
block  on  the  east  rises  abruptly  several  hundred  feet  above  the  neighboring 
portion  of  the  western  block.  It  is  along  this  line  of  disturbance  that  the 
St.  Peter  and  Lower  Magnesian  strata  are  brought  to  view  on  the  Illinois 
and  Rock  rivers  and  on  Elkhorn  Creek.  Its  trend  from  the  Illinois  River 
northward  is  about  southeast  to  northwest.  Sections  in  the  lead  region 
indicate  that  it  continues  in  subdued  form  some  distance  into  southwestern 
Wisconsin.  Its  southward  continuation  from  the  Illinois  is  readily  traceable 
as  far  as  Livingston  County  by  disturbances  shown  in  coal  shafts,  as  noted 
by  the  Illinois  survey.     Farther  south  its  course  is  less  definitely  known. 

There  is,  over  much  of  western  Illinois,  a  gradual  descent  from  the 
western  border  of  the  State  to  this  line  of  disturbance.     In  the  latitude  of 


554 


THE  ILLINOIS  GLACIAL  LOBE. 


Peoria  it  averages  about  7  feet  per  mile,  and  is  not  greatly  different  in  por- 
tions of  the   State  farther  north.     The   eastward  descent  across  western 


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Illinois   appears   to   rontinue    gradual    as   far   south   as   the   Cap   an   Gr^s 
uplieaval,  near  the  mouth  of  tlie  Illinois,  and,  so  far  as  known  to  the  writer, 


WELLS  OF  ILLINOIS.  555 

there  is  no  marked  disturbance  along-  the  Mississippi  north  from  that  point. 
From  the  Cap  au  Grfes  disturbance  southward  to  the  Ozark  Ridge,  in  south- 
ern HHnois,  a  diflPerent  field  is  found.  Disturbances  are  frequent  along-  the 
Mississippi.  There  is  also  in  this  disti-ict  a  more  abrupt  descent  in  the  floor 
of  the  Coal  Measures  within  a  few  miles  east  of  the  Mississippi.  Thus,  in 
passing  from  the  east  bluff"  of  the  river  in  western  St.  Clair  County  to 
Belleville  a  descent  of  650  feet  is  made  within  a  distance  of  10  miles. 

ESSENTIAL    CONDITIONS    FOR    ARTESIAN   WELLS. 

Since  the  essential  conditions  for  obtaining  artesian  wells  have  been 
discussed  at  some  length  by  Prof  T.  C.  Chamberlin  in  a  report  of  this  Sur- 
vey,^ only  a  brief  outline  of  their  conditions  is  here  attempted.  The  essen- 
tial conditions  for  artesian  wells  are:  (1)  A  suitable  exposure  of  a  porous 
rock  in  a  humid  region,  i.  e.,  a  favorable  absorbing  area;  (2)  the  extension 
of  the  porous  bed  from  the  absorbing  area  out  underneath  regions  havino- 
a  lower  altitude,  i.  e.,  a  favorable  transmitting  area;  (3)  a  partial  or  full 
obstruction  to  the  escape  of  the  waters  at  a  lower  level  than  the  absorbing 
area.  The  porous  rock  is  usually  confined  between  beds  which  are  less 
porous  and  which  act  as  a  partial  or  complete  obstruction  to  the  escape  of 
the  waters.  It  is  not  necessarj^,  however,  that  these  beds  should  be  per- 
fectly water-tight;  indeed,  such  is  rareh'  the  case.  It  is  only  necessary 
that  the  confining  beds  should  be  such  as  to  prevent  most  of  the  water  from 
escaping.  In  some  cases  the  water  contained  in  semiporous  beds  overlying 
the  porous  rock  aids  in  preventing  the  escape  of  water  from  the  porous  bed 
at  points  between  the  absorbing  area,  or  fountain  head,  and  the  well.  In 
connection  with  this  condition  Professor  Chamberlin  remarks:'^ 

I  conceive  that  one  of  the  most  favorable  conditions  for  securing  a  fountain  is 
found  where  thick,  semiporous  beds,  constantly  saturated  with  water  to  a  greater 
height  than  the  fountain  head,  lie  upon  the  porous  stratum  and  occupy  the  whole 
country  between  the  well  and  its  source.  This  is  not  only  a  good  but  an  advan- 
tageous substitute  for  a  strictly  impervious  confining  bed.  Under  these  conditions 
limestone  strata  reposing  on  sandstone  furnish  an  excellent  combination. 

This  condition  prevails  extensively  in  northern  Illinois.  The  absorbing 
area  for  the  artesian  waters  of  northern  Illinois  is  found  in  southern  Wis- 
consin, the  porous  rock  thence    dipping    southward  to  northern   Illinois. 

'Fifth  Ann.  Kept.  U.  S.  Geol.  Survey,  1885,  pp.  131-173. 
=  Loc.  cit.,  p.  140. 


556  THE  ILLINOIS  GLACIAL  LOBE. 

Between  this  absorbing  area  and  the  wells  is  a  district  in  which  the  porous 
bed  is  overlain  bv  limestone  or  semiporous  rock,  and  also  by  drift  beds, 
which  aftbrd  much  opportunity  for  absorption  of  water.  These  overljdng- 
beds,  however,  have  altitudes  fully  as  great  as  portions  of  tlie  absorbing- 
area,  and  hence,  when  filled  with  water,  the  downward  pressure  equals  or 
exceeds  that  of  the  upward  pressure  of  water  from  the  porous  beds,  and 
thus  they  prevent  escape  as  effectually  as  a  series  of  impervious  beds.  The 
-s-ariabilitv  of  head  displayed  by  wells  in  northern  Illinois  which  obtain 
their  main  supplj^  from  the  St.  Peters  formation  is  probably  largely  due  to 
the  influx  of  water  from  overlying  beds  in  the  district  between  the  fountain 
head  and  the  well.  The  main  absorbing  areas  for  the  Potsdam  and  St. 
Peter  formations  are  shown  in  PI.  XXII,  which  is  compiled  chiefly  from 
State  geological  maps  and  was  first  published  by  the  writer  in  the  Seven- 
teenth Annual  Report  of  this  Survey. 

A  topogTaphic  map  of  the  St.  Peter  sandstone,  showing  also  the  dis- 
tribution of  artesian  wells  and  deep  borings  and  of  the  principal  areas 
where  flowing  wells  are  obtained  from  the  drift,  is  presented  in  Pi.  XXIII, 
a  map  already  published  in  the  Seventeenth  Annual  Report.  The  three 
sections  in  figs.  20,  21,  and  22  illustrate  the  above  statements  concerning 
the  attitude  of  the  rock  formations  and  correspond  to  the  lines  A — A,  B — B, 
and  C — C  on  PI.  XXIII.  The  data  used  in  figs.  7  and  8  are  largel}' 
obtained  from  records  of  wells  collected  by  the  writer,  but  some  of  the 
data  are  from  a  report  by  Daniel  W.  Mead,  bearing  upon  the  liydrogeo- 
logy  of  the  Mississippi  Basin.^  The  data  in  fig.  9  are  largely  based  upon 
a  special  study  by  Prof.  J.  A.  Udden  of  a  line  leading  from  Rock  Island 
eastward  across  Illinois,  which  was  made  for  the  Illinois  Board  of  World's 
Fair  Commissioners.^  It  brings  out  clearly  the  monoclinal  fold  separating 
the  two  blocks  of  eastward-dipping-  strata  just  noted.  For  a  more  complete 
discussion  of  artesian-well  conditions  in  Illinois,  reference  may  be  made  to 
the  report  by  the  Avriter  contained  in  the  Seventeenth  Annual  Report  of 
this  Survey.  Many  records  of  wells  appear  in  the  detailed  discussion 
below. 

'  Hydiogeology  of  tlie  Upper  Mississippi  Valley  and  some  of  tlie  adjoiniug  Territory,  by  Daniel 
W.  Mead,  ('.  E. :  .lour.  Assoc.  Eng.  Soc,  Vol.  XIII,  No.  7,  July,  1894.     G8  pages,  with  G  maps. 
-See  Final  Report  Illinois  Board  of  World's  Fair  Commissioners,  1895,  pp.  115-1.'51. 


U.S. GEOLOGICAL  SURVEY. 


MONOGRAPH    XXXVIII  PL.  XXII 


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WELLS  OF  ILLINOIS.  557 

RELATION    OF    THE   DRIFT    TO    ORDINARY    WELLS. 

The  g-eneral  relation  of  the  drift  to  the  ordinary  wells  of  Illinois  and 
western  Indiana  i§  set  forth  in  PL  XXIV.  It  will  be  observed  that  with  the 
exception  of  a  few  counties  in  the  northern  and  southern  ends  of  Illinois 
the  wells  are  largely  obtained  from  the  drift.  This  relation  is  shown  in 
detail  in  the  discussion  which  follows. 

GAS    WELLS. 

Wells  which  yield  an  inflammable  gas  are  found  in  many  counties  of 
the  State,  instances  of  which  are  presented  in  connection  with  the  water 
wells.  This  gas  in  some  cajses  appears  to  be  derived  from  the  decay  of 
vegetal  matter  contained  in  the  drift,  either  in  the  form  of  peat  and  muck 
beds  or  as  timber  scattered  through  the  drift.  It  is  probable,  however,  that 
the  underlying  rocks  are  an  important  if  not  the  chief  contributor,  m  which 
case  the  pressure  of  the  g'as  within  the  drift  is  due  to  the  resistance  which 
compact  drift  beds  offer  to  the  escape  of  the  gas.  Not  only  the  shales  but 
certain  limestones  in  this  region  have  been  found  to  contain  gas.  But  it 
does  not  seem  to  have  accumulated  in  such  great  quantities  as  in  the  gas 
fields  of  the  neighboring  States  of  Indiana  and  Ohio.  It  rarely  reaches  a 
pressure  of  20  pounds  per  square  inch. 

TABUIiATIOIf  OF  SOURCES  FOR  CITY  AVATER  SUPPIiY. 

The  following  table  embraces  all  the  cities  and  villages  in  Illinois  hav- 
ing water  works  whose  source  of  supply  has  been  ascertained.  It  is  based, 
in  part,  upon  data  collected  by  the  writer,  and  in  part  upon  data  found  in 
the  Manual  of  American  Water  Works  for  1897.'  Through  the  aid  of  this 
publication  the  statistics  have  been  properly  rounded  out  and  brought  down 
to  date.  In  towns  with  the  letter  "M"  appended  the  Manual  of  Water 
Works  is  the  authority.  The  wells  are  classified  according  to  the  scheme 
above  outlined  (pp.  550-551).  Man^^  details  concerning  the  city  water 
supplies  appear  in  the  subsequent  discussion  by  counties. 

'  The  Manual  of  American  Water  Works,  1897,  edited  by  M.  N.  Baker,  Engineering  News  Pub.  Co., 
New  York.  Contains  the  history  and  descriptions  of  the  source  and  mode  of  supply,  pumps,  reser- 
voirs, standpipes,  distribution  sj'stems,  pressures,  consumption,  revenue  and  expenses,  cost,  debt,  and 
sinking  fund,  etc.,  of  the  water  works  of  the  United  States  and  Canada. 


55R 


THE  ILLINOIS  GLACIAL  LOBE. 
Sources  of  water  supply  for  towns  in  lUinois. 


Aleilo 

Alexis  (M) 

Algonquin 

Alton 

Amboy 

Areola 

Atlanta 

Aurora 

Austin 

Avon(M) 

Barry 

Batavia(M) 

Beardstowu 

Belleville 

Belvidere 

Bement 

Bloomingtou 

Buckley  (M) 

Buda 

Bushnell 

Cabery  (M)  

Cairo 

Cambridge  (M)... 

Canton 

Carbon  Hill  (M).. 

Carlinville 

Carlyle 

Carmi  (M) 

Carrollton 

Carthage 

Centralia 

Chadwick 

Champaign 

Charleston 

Chats  worth 

Chenoa 

Chicago 

Chicago  Heights 

Chillicothc 

Cissna  I'ark  (M). 

Clayton  (M) 

Clinton 

Collinsville 


Population  in 
1890. 

Source. 

1,601 

Kock,  class  7. 

562 

Drift,  class  3. 

300 

Spriug.s. 

10,  294 

River. 

2,257 

Rock,  class  7. 

1,733 

Drift,  class  3. 

1,178 

Drift,  class  3. 

19,  688 

Rock,  class  7. 

4,051 

Rock,  class  7. 

692 

Rock,  class  6. 

1,354 

Rock,  class  7. 

3,543 

River  (?). 

4,226 

Drift,  class  4. 

15, 361 

Creek. 

3,877 

Rock,  class  7. 

1, 129 

Drift,  class  3. 

20, 484 

Drift,  class  4. 

433 

Drift,  class  4. 

990 

Rock,  class  7. 

2,314 

Drift,  class  3. 

342 

Well,  240  feet,  class  3  ( ?). 

10, 324 

River. 

940 

Deep  well,  class  7  (?). 

5,604 

Rock,  class  7. 

(?) 

Rock,  class  7. 

3,293 

Creek. 

1,784 

River. 

2,785 

River. 

2,258 

Rock,  class  7. 

1,654 

Rock,  class  7. 

4,763 

Creek. 

(?) 

Rock,  class  6. 

5,839 

Drift,  class  4.                   ' 

4,135 

River. 

827 

Drift,  class  3. 

1,226 

Rock,  class  6. 

1, 099, 850 

Lake. 

(?) 

Rock,  class  6. 

1,632 

Alluvium,  class  2 

(?) 

Drift,  class  4. 

1,033 

Rock,  class  6. 

2,538 

Drift,  class  3. 

3,498 

Rock,  class  7. 

WELLS  OF  ILLIT^OIS. 
Sources  of  water  supply  for  towns  in  Illinois — Continued. 


559 


1^0  wn. 


Crescent  (M) 

Danvers 

Danville 

Decatur   

Dekalb  

Delavan  

Des  Plaines  (M) 

Dixon 

Downers  Grove  (M) 

Dundee 

DwiK-ht 


Earlville . 


East  Dubuque- - . 
East  St.  Louis-. - 

EfiHngUam 

Elgin 

Elnihurst  (M)  ... 
Elmwood  (M)  . . . 

Elpaso 

Eureka 

Evanston 

Fairbury 

Farmer  City 

Farmington  (M) . 
Flannigan  (M)  .. 

Forrest  

Forreston 


Freeport 

Fulton 

Galena 

Galesburg  - . . 

Galva  (M)... 

Geneseo   

Geneva  

Gibson 

Oilman 

Granite  (M)  , 
Grayville  ... 
Greenville.-. 
Harvev 


Popnlatlou  in 
1890. 

Source. 

(?) 

Drift,  class  4. 

50.5 

Drift,  class  3. 

11,  491 

River. 

16, 841 

Eiver. 

2,579 

Eock,  class  7. 

1,176 

Drift,  class  3. 

986 

Rock,  class  6. 

5, 161 

Rock,  class  7. 

960 

Deep  well,  class  (?). 

(?) 

Springs. 

1,354 

Drift,  class  4. 

1,058 

|Rock,  clnss  6. 
(.Drift,  class  4. 

1,069 

Rock,  class  7. 

15, 169 

River. 

3,260 

River. 

17,  823 

River. 

1,050 

Spring. 

1,548 

Rock,  class  7. 

1,353 

Drift,  class  3. 

1,481 

Drift,  class  3. 

12,  762 

Lake. 

2,324 

Rock,  class  7. 

1,367 

Drift,  class  4. 

1,375 

Rock,  class  7  (?). 

384 

'•Artesian  -well,"  class 

(?). 

1,021 

Drift,  class  3. 

1,  118 

Rock,  class  7. 

10, 189 

J  Alluvium,  class  2. 
•^Rock,  class  7. 

2,099 

Rock,  class  7. 

5,635 

Rock,  class  7. 

15, 264 

JRock,  class  7. 
^Drift,  class  4. 

2,409 

Well,  class  ( ?). 

3,182 

Eock,  class  7. 

1,692 

Rock,  class  7. 

1,803 

Drift,  class  3. 

1,112 

Drift,  class  4. 

(?) 

River. 

1,999 

River. 

1,868 

Drift,  class  3. 

(?) 

Rock,  class  7.. 

560  THE  ILLINOIS  GLACIAL  LOBE. 

Sources  of  water  supply  for  toiciis  in  Illinois — Coiitiimed. 


Town. 


Havana 

Henuepin 

Highland  Park 

Hillsboro 

Hinsdale 

Hoopestown. .. 

Ipava 

Jacksonville  .. 
Jerseyville  . . .  _ 

Joliet 

Kankakee 

Keitbsburg 

Kempton  (JI). . 

Ke  wanes 

Kirkwood  (M) . 

Kuiixville 

Lacon  (M) 

Lagrange 

Laliarpe 

Lake  Forest .  - . 
Lanark  

Lasalle . 

Lemont 

Lena  (M) 

Leroy 

Lewiston 

Lexington  (M). 

Lincoln 

Litchfield 

Lockport 

Macomb 

Macon 

Mackinaw 

Madison 

Marengo 

Maroa 

Masim 

MattooM 

May  wood  (M)  . 

Mcndou 

Meiidota 


Popnlation  in 

1890. 

Source. 

2,  525 

/Alluvium,  class  2. 
'Drift,  class  4. 

.->74 

Rock,  class  7. 

2, 163 

Lake. 

2,  500 

■Springs. 

1,  584 

Rock,  class  7. 

1,911 

Rock,  class  7. 

667 

Rock,  class  7. 

12,  935 

Rock,  class  7. 

3, 207 

Rock,  class  7. 

23,  264 

Rock,  class  7. 

9,025 

River. 

1,484 

Alluvium,  class  2. 

201 

Drift,  class  3. 

4,569 

Rock,  class  7. 

949 

Rock,  class  6  ( f ). 

1,728 

Rock,  class  7. 

1,649 

Well,  class  (f). 

2,314 

Rock,  class  7. 

1,  113 

Drift,  class  3. 

1,203 

Lake. 

1,295 

Drift,  class  3. 

9,855 

iRock,  class  7. 
ISprings. 

(n 

Rock,  class  7. 

1,270 

Deep  -n-ell,  class  (?). 

1,258 

Drift,  class  3. 

2,166 

Alluvium,  class  2. 

1,187 

Well,  class  ( ?). 

6,725 

Creek. 

5,811 

Creek. 

2,449 

Rock,  class  7. 

4,052 

Rock,  class  7. 

819 

Drift,  class  3. 

545 

Drift,  class  3. 

(?) 

River. 

1,445 

Drift,  class  4. 

1.164 

Drift,  class  3. 

1,  869 

Drift,  class  3. 

6,833 

Drift,  class  3. 

2,076 

Rock,  class  7. 

640 

Rock,  class  7 

3, 542 

Rock,  class  7. 

WELLS  OP  ILLINOIS. 

Sources  of  ivater  supply  for  towns  in  Illinois — Continued. 


561 


Town. 


Metamora 

Metropolis 

Milan 

Milford(M) 

Minonk 

Moline 

Monmouth 

Monticello 

Morgan  Park 

Morris 

Morrison 

Morrison  ville 

Morton 

Mount  Cariiiel 

Mount  Carroll 

Mount  Morris 

Mount  Pulaski  (M) 

Mount  Sterling 

Mount  Vernon 

Moweaqua  (M) 

Murphysboro 

Newton 

Nokomis 

Norwood  Park 

Oak  Park 

Ohio 

Oluey  

Onarga 

Orangeville 

Oregon  (M) 

Oswego  (M) 

Ottawa , 

Pana 

ParkEidge  (M) 

Paris 

Pawpaw 

Paxton 

Pecatonioa 

Pekin 

Peoria 

Peru 

Petersburg 

MON  XXXVIII 3(j 


Population  in 
1890. 

Source. 

758 

Drift,  class  3. 

3,593 

River. 

692 

Eock,  class  7. 

957 

Drift,  class  4. 

2,316 

Eock,  Class  7. 

12,  000 

River. 

5,936 

Eock,  class  7. 

1,643 

Drift,  class  3. 

1,027 

Eock,  class  7. 

3,653 

Eock,  class  7. 

2,088 

Springs. 

844 

Drift,  class  3. 

657 

Drift,  class  3. 

3,  376 

Alluvium,  class  2. 

1,836 

Eock,  class  7. 

895 

Eock,  class  6. 

1,357 

Well,  class  ( ?). 

1,655 

Drift,  class  3. 

3,233 

Impounded  water. 

848 

Well,  class  ( ?). 

3,880 

Eiver. 

1,428 

Eiver. 

1,305 

Drift,  class  3. 

(?) 

Eock,  class  7. 

4,771 

Eock,  class  7. 

360 

Drift,  class  3. 

3,831 

Eiver. 

994 

Drift,  class  4. 

347 

Eock,  class  6. 

1,566 

\Yell,  class  ( ?). 

641 

Well,  class  ( ?). 

9,985 

Eock,  class  7. 

5,077 

Drift,  class  3. 

987 

Eock,  class  7. 

4,966 

Drift,  class  3. 

(?) 

Eock,  class  7. 

2,177 

Drift,  class  4. 

1,059 

Springs. 

6,347 

Drift,  class  4. 

41,  024 

Drift,  class  4. 

5,550 

Eock,  class  7. 

2,342 

Alluvium,  class  2. 

562 


THE  ILLINOIS  GLACIAL  LOBE. 

Sources  of  icater  supply  for  towns  in  Illinois — Continued. 


Pinekneyville  . 

Pittsfield 

Piano  (M) 

Pontiac  (SI)  ... 

Princeton 

Quincy 

Rantoul  (M)... 

Riverside 

Rochelle 

Rock  Falls 

Rockford 

Rock  Island  ... 
Roseville  (M)  . 
Rossville  (M)  . 
Rushville  (M)  . 

Sandwich 

Savanna 

Shannon  

Sheffield  (M)  . 
Shelby ville  ... 
Somonauk(M) 
Springfield . . . . 

Staunton 

Sterling 

Stockton  (M) . 

Streator 

Sullivan 

Sycamore 

Taylorville.  ... 
Tolono(M).... 

Urbana 

Upper  Alton . . 

Vandalia 

Venice 

Walnut 

Warren 

Warsaw 

Washington  . . 

Waterloo 

Waterman  (M) 

Watseka 

Wankegaii  ... 


Population  in 
1890. 

Source. 

1,298 

Rock,  class  7. 

2,295 

Rock,  class  7. 

1,825 

Rock,  class  7. 

2,784 

River. 

3,396 

Rock,  class  7. 

31, 494 

River. 

1,074 

Drift,  class  3. 

(?) 

Rock,  class  7, 

1,789 

Springs. 

1,900 

Rock,  class  7. 

23,  584 

Rock,  class  7. 

13,  624 

River. 

788 

WeU,  class  ( ?). 

879 

Well,  class  ( ?). 

2,031 

Springs. 

2,516 

Drift,  class  4. 

3,097 

Rook,  class  7. 

591 

Rock,  class  6. 

993 

Well,  class  (f). 

3.162 

River. 

468 

Well,  class  ( ?). 

24,  963 

Alluvium,  class  2. 

2,209 

Impounded  water. 

5,824 

Rock,  class  7. 

379 

Well,  class  (?). 

11,  414 

River. 

1,468 

Drift,  class  3. 

2,987 

Drift,  class  4. 

2,829 

Drift.,  class  3. 

902 

Well,  class  (?). 

3,511 

Drift,  class  4. 

1,803 

Alluvium,  class  2. 

2,144 

River. 

932 

River. 

605 

Drift,  class  3. 

1,172 

Rock,  class  7. 

2,721 

Rock,  class  7. 

1,301 

Drift,  class  4. 

1,860 

Impounded  water. 

351 

Well,  class  ( <). 

2,017 

Drift,  class  4. 

4,915 

Lake. 

WELLS  OF  ILLIISrOIS. 

Sources  ofivater  supply  for  towns  in  Illinois — Continued. 


563 


Town. 


Population  in 
1830. 

Soi 

368 

Drift,  class  3. 

1,053 

Rock,  class  7. 

451 

Well,  class  (?) 

1,622 

Kock,  class  6. 

1,458 

Lake. 

1,576 

Elver. 

1,079 

Lake. 

1,683 

Rock,  class  7. 

375 

Springs. 

Waynesville  (M) 

Wenona 

Western  Springs  (M) 

Wheaton 

Wilmette 

Wilmington 

Winnetka 

Woodstock 

Yorkville 


From  the  above  table  it  appears  that  in  69  cities  and  villages,  or  about 
one-third  of  the  number  in  Illinois  now  having  waterworks,  the  supply  is 
obtained  from  rock  wells  either  flowing  (artesian)  or  with  strong  hydrostatic 
pressure.  Of  the  250,000  inhabitants  of  these  cities  and  villages  it  is  prob- 
able that  more  than  one-half  are  dependent  upon  the  public  water  supply. 
In  some  cities  and  in  many  of  the  villages  a  large  part  of  the  population 
prefer  to  obtain  their  supply  from  private  wells  or  cisterns,  a  preference 
which  is  due  in  part  to  inability  to  meet  the  city  water  tax  and  in  part  to 
objectionable  properties  of  the  water.  It  should  be  stated,  however,  that 
throughout  much  of  northern  Illinois  wells  of  this  class  furnish  wholesome 
and  very  palatable  water.  It  should  be  noted  that  wells  of  this  kind  are 
extensively  used  in  various  industries  in  the  city  of  Chicago  and  in  several 
other  cities  in  northern  lUinois,  the  aggregate  amouW  of  water  thus  obtained 
in  Chicago  approximating  that  furnished  by  the  city  waterworks. 

In  contrast  with  the  extensive  use  of  this  class  of  rock  wells  as  a  city 
supply  is  the  use  of  rock  wells  having  weak  hydrostatic  pressure.  Only 
twelve  villages,  with  a  combined  population  of  scarcely  10,000,  are  known 
to  depend  upon  the  latter  class  of  wells.  It  is  possible,  however,  that  a  few 
others  reported  in  the  Waterworks  Manual  may  be  of  that  class.  Such 
wells  rarely  furnish  an  adequate  supply  for  a  large  town. 

The  table  indicates  that  aside  from  Chicago,  with  its  population  of 
more  than  one  million,  there  are  52  cities  and  villages,  with  a  combined 
population  of  nearly  300,000,  in  which  surface  water  constitutes  the  public 
supply.     In  Chicago  the  population  is  mainly  dependent  upon  such  water. 


564  THE  ILLINOIS  GLACIAL  LOBE, 

In  the  other  cities,  aud  especially  in  the  villages,  private  wells  and  cisterns 
are  used  extensively. 

Turning  to  di'ift  wells,  it  is  found  that  22  cities  and  villages,  with  a 
combined  population  of  about  100,000,  obtain  their  public  supply  from 
wells  in  glacial  di-ift  which  have  strong  hydi'ostatic  pressiu-e,  many  of  them 
being  flowing  wells.  In  38  other  cities  and  villages,  with  a  population 
aggregating  about  60,000,  drift  wells  ai'e  in  use  which  display  no  marked 
hydrostatic  pressure.  There  are  only  three  cities  with  a  population  of  more 
than  2,000  in  which  this  class  of  wells  constitutes  the  public  supply,  namely, 
Mattoon,  Pana,  and  Paris.  There  are  9  cities  and  Aallages,  with  a  combined 
population  of  about  50,000,  in  which  the  public  supply  is  obtained  from 
beds  of  alluvium.  Among  these  cities  Springfield  has  been  included,  its 
supply  being  from  infiltration  wells  along  the  bank  of  the  Sangamon  River. 
The  supply  at  Freeport  is  from  wells  sunk  below  the  level  of  the  Pecatonica 
River,  and  these  may  possibly  be  referable  to  class  3  rather  than  to  tlais 
class.  However,  the  material  penetrated  appears  to  be  alluvial  rather  than 
glacial. 

DETAIIiEI)  DISCUSSION. 

With  this  brief  statement  concerning  the  sources  for  supply  in  the 
cities  of  Illinois,  we  pass  to  the  detailed  discussion  of  wells  by  counties. 
The  counties  are  taken  up  in  the  order  of  their  numbering  on  PL  XX. 
The  discussion  begins  in  the  northern  tier  of  counties  and  passes  back  and 
forth  in  successive  tiers,  terminating  at  the  southern  end  of  the  State.  The 
uuirlaciated  comities  at  the  southern  end  of  the  State  are  discussed  as  a 
single  district  and  very  briefly,  though  they  present  probably  a  greater 
variety  of  sources  for  water  supply  than  almost  any  other  area  of  equal 
size  within  the  State.  The  writer's  examination  of  that  district  has  been 
too  incomplete  to  enable  him  to  treat  adequately  of  its  water  resources. 

JO  DAVIESS  COUNTY. 
GENERAL   STATEMENT. 

This  county  is  situated  in  the  extreme  northwest  corner  of  the  State  and 
has  an  area  of  663  square  miles.  The  greater  part  lies  within  the  Driftless 
Area,  the  glaciated  portion  occupying  only  about  100  square  miles  on  the 
eastern  border.  The  cfriftless  portion,  however,  is  covered  with  a  nearly 
continuous  sheet  of  loess,  the  thickness  of  which  along  the  borders  of  tlie 


WELLS  OF  JO  DAVIESS  COUNTY,  ILLINOIS.  565 

Mississippi  will  average  about  20  feet,  but  the  average  for  the  county  will 
probably  not  exceed  10  feet.  Along  the  Mississippi  Valley  on  the  west 
borders  of  the  county  there  is  a  filling  of  sand  and  gravel  about  150  feet 
in  depth,  as  shown  by  wells  on  the  Iowa  side  at  Dubuque  and  Sabula.  The 
tributaries  of  the  Mississippi  in  this  county  have  been  silted  up  to  a  level 
corresponding  with  the  filling  in  the  Mississippi  Valley.  The  material  in 
these  tributaries  is  usually  a  rather  compact  clay. 

Wells  in  the  valley  of  the  Mississippi  obtain  water  at  depths  of  20  to 
40  feet  without  entering  the  rock.  In  the  tributaries  of  the  Mississippi  a 
few  wells  obtain  water  from  the  clay  deposits,  but  as  a  rule  the  residents 
depend  upon  either  springs  from  the  limestone  blufi"s  or  wells  sunk  into  the 
rock.  The  wells  on  the  uplands  in  the  unglaciated  part,  and  to  some  extent 
in  the  glaciated  part,  obtain  their  water  from  limestone  at  depths  ranging 
from  40  feet  to  150  feet  or  more.  Usually  a  good  supply  maybe  obtained 
at  less  than  100  feet.  In  the  glaciated  portions  of  the  county  the  drift  is 
generally  too  thin  to  afi'ord  strong  wells.  There  is,  however,  just  north  of 
Stockton  a  preglacial  valley  filled  to  a  depth  of  at  least  140  feet,  which 
furnishes  strong  wells,  some  of  which  overflow.  Tln-oughout  the  county  the 
water  is  of  excellent  quality,  although  very  hard.  The  expense  of  sinking- 
wells  to  rock  being  heavy,  many  of  the  residents  resort  to  cisterns  for  a 
water  supply.  Impounded  water  is  also  used  quite  extensively  to  supply 
the  stock  on  farms. 

INDIVIDUAL   WELLS. 

The  city  water  supply  at  Galena,  the  county  seat,  is  obtained  from  an 
artesian  well  sunk  to  a  depth  of  1,200  feet  and  obtaining  its  supply  from  the 
Potsdam  sandstone.  It  has  a  head  85  feet  above  the  surface  and  a  capacity 
estimated  a,t  166  gallons  per  minute.  An  analysis  made  by  the  State  Board 
of  Health  appears  in  the  Seventeenth  Annual  Report  of  this  Survey.^  Wells 
are  obtained  in  the  vicinity  of  Galena  from  the  limestone  at  depths  of  60 
to  200  feet. 

At  East  Dubuque  the  town  well  is  artesian  and  has  a  depth  of  940  feet. 
The  water  is  obtained  from  Potsdam  sandstone  and  has  a  head  nearly  100 
feet  above  the  surface  and  a  capacity  estimated  at  420  gallons  per  minute. 
Aside  from  the  artesian  well  there  are  a  few  shallow  wells  obtaining  their 
supply  from  the  gravel  and  sand  of  the  Mississippi  Valley. 

'Pnrt  IT,  pp.  820  and  827. 


566 


THE  ILLINOIS  GLACIAL  LOBE. 


At  Wan-en  and  in  that  ^-icinity  the  best  wells  are  50  to  150  feet  deep 
and  obtain  water  from  the  Galena  limestone.  The  altitude  being  high 
(about  1,000  feet  above  tide),  the  water  level  in  the  wells  is  so  low  that 
windmills  are  usuallv  employed  to  raise  the  water.  A  large  pi'oportion  of 
the  residents  of  the  village  depend  upon  cistern  water.  The  Manual  of 
American  Waterworks  (1897)  reports  that  a  well  has  recently  been  sunk 
to  a  depth  of  900  feet  which  furnishes  the  public  water  supply. 

No  data  were  obtained  concerning  wells  in  other  villages  of  the  county, 
but  a  few  records  were  obtained  of  wells  in  the  glaciated  poi-tion  between 
Stockton  and  Nora.  These  usually  enter  rock  at  20  to  30  feet,  but  occa- 
sionally the  di-ift  is  thicker.  In  the  preglacial  valley  referred  to  above, 
which  passes  in  an  east-west  coui'se  midway  between  these  villages,  several 
well  records  were  obtained  which  are  tabulated  below: 

Wells  in  a  preglacial  valley  north  of  Stockton. 


Owner. 


Altitude 
(above  tide). 


Deptli. 


Head  from  surface. 


Mr.  Keplinger 

A.  A.  Simmons 

Andrew  Simmons... 

Charles  Kappas 

Theodore  Hopkins.. 

W.  Legrand 

Mrs.  M.  L.  Grouse. . . 
Mrs.  M.  L.  Grouse. .. 

G.  W.  Curtis 

Frank  Weighers 

Mrs.  Emily  Goomler 

M.  Werkheiser 

Richard  Oliver 


Feet. 
930 
950 
950 
950 
940 
940 
940 
930 
950 
935 
970 
970 
970 


Feet 

50 

72 

77 

105 

134 

135 

40 

140 

96 

110 

135 

85 

60 


Overflows. 
10  feet  below. 
10  feet  below. 
10  feet  below. 
3  feet  below. 
3  feet  below. 
Ovex-flows. 
Overflows. 
15  feet  below. 
10  feet  below. 
35  feet  below. 
35  feet  below. 
35  feet  below. 


The  majority  of  the  wells  in  the  above  list  peneti'ate  50  to  70  feet 
of  compact  clay  before  entering  a  water-bearing  bed,  and  at  Mrs.  Grouse's 
deeper  well  130  feet  of  clay  was  penetrated.  The  last  thi-ee  wells  in  the 
list  are  situated  on  a  low  drift  ridge  and  their  sections  show  a  larger  propor- 
tion of  gi'avel  and  sand  than  the  wells  on  the  plane  sui-face.  The  strong 
hydrostatic  pressure  probably  results  from  an  absorption  of  water  on  the 

None  of  the  wells  in  this  list  entered   rock. 


neighboring 


higher  land. 


WELLS  OF  STBPHBFSON  COUNTY,  ILLINDIS.  567 

although  they  are  all  situated  within  5  miles  of  the  glacial  boundary,  and 
some  of  them  within  2  miles. 

STEPHENSON  COUNTY. 
GENERAL   STATEMENT. 

Stephenson  County  is  situated  immediately,  east  of  Jo  Daviess  County, 
on  the  north  border  of  the  State,  with  Freeport  as  its  county  seat,  and  has 
an  area  of  560  square  miles.  It  is  drained  chiefly  by  Pecatonica  River, 
which  traverses  its  northern  and  eastern  portions.  With  the  exception  of 
a  few  square  miles  in  the  northwest  corner,  this  coimty  is  covered  with 
glacial  drift.  The  thickness  of  the  drift  is  insufficient  to  conceal  the  main 
preglacial  valleys,  and  extensive  upland  tracts  have  rock  within  a  few  feet 
of  the  surface.  The  average  of  the  well  sections  reaching  rock  so  far  as 
collected  are  as  follows:  Forty-eight  wells  on  uplands  and  slopes,  31  feet; 
12  wells  along  preglacial  valleys,  130  feet.  Of  these,  17  wells  are  in 
Freeport  and  vicinity,  and  average  50  feet.^  The  drift,  as  already  noted, 
is  frequently  aggregated  in  small  knolls  and  ridges  having  a  gi-avelly  con- 
stitution. At  such  places  it  has  exceptional  thickness.  Aside  from  the 
preglacial  valleys  and  the  knolls  and  ridges  just  refen-ed  to,  the  drift  is 
usually  too  thin  to  be  depended  upon  as  a  supply  for  wells. 

Most  wells  in  this  county,  as  in  Jo  Daviess  County,  obtain  water  from 
the  Galena  limestone  at  depths  ranging  from  30  or  40  feet  up  to  about 
200  feet.  Their  average  depth  is  somewhat  less  than  in  Jo  Da^dess 
Coimty.  In  the  preglacial  valleys  and  in  some  of  the  drift  knolls  and 
ridges  strong  wells  are  obtained  at  convenient  depths — 25  to  50  feet. 

The  highest  portions  of  the  county  are  very  thinly  coated  with  drift, 
rock  usually  being  entered  at  15  to  20  feet  or  less.  A  few  instances,  how- 
ever, are  reported  in  which  the  drift  has  a  thickness  of  80  feet  or  more. 
The  lowlands  are  generally  covered  to  a  sufficient  depth  to  afford  an  ade- 
quate supply  of  water  without  entering  the  rock;  but  there  are  small  areas 
within  the  lowland  districts  in  which  rock  is  very  near  the  surface.  These 
contrasts  in  the  thickness  of  drift,  both  on  highland  and  lowland  tracts,  are 
set  forth  in  the  table  of  wells  given  below. 

'  Many  of  the  well  records  were  collected  by  Mr.  Oscar  Hershey  during  or  prior  to  his  connec- 
tion with  this  Survey. 


568 


THE  ILLINOIS  GLACIAL  LOBE. 


INDIVIDirAL   WELLS. 


The  public  water  supply  for  the  city  of  Freeport  is  obtained  mainly 
from  a  series  of  tubular  wells  sunk  to  a  depth  of  about  40  feet  through  the 
alluAaum  and  possibly  through  glacial  deposits  of  the  Pecatonica  Valley. 
The  supply  of  water  is  derived  fi-om  sand  just  above  the  rock.  The 
Manual  of  American  Waterworks  (1897)  reports  that  a  part  of  the  supply 
is  from  wells  about  200  feet  in  depth,  which  enter  the  St.  Peter  sandstone. 
This  sandstone  is  stated  by  Mr.  Hershey  to  .set  in  about  110-130  feet 
below  the  surface  of  the  Pecatonica  flood  plain  at  Freeport. 

Several  private  wells  in  Freepoi't  have  been  sunk  to  the  St.  Peter 
sandstone,  and  tliis  sandstone  is  occasionally  encountered  in  wells  in  the 
north  part  of  the  county.  Near  Orangeville  the  St.  Peter  sandstone  comes 
nearly  to  the  surface.  The  waterworks  supply  for  that  village  is  fi-om  a 
well  142  feet  in  depth,  which  is  mainly  through  St.  Peter  sandstone. 

The  public  water  supply  at  Lena  is  from  a  deep  well,  but  the  precise 
depth  has  not  been  ascertained.  E.ock  is  usually  entered  in  that  vicinity 
at  about  15  feet. 

In  the  vicinity  of  Kent  rock  is  entered  at  about  30  feet.  The  railway 
well  at  Kent  Station  is  275  feet  in  depth  and  obtains  its  supply  in  lime- 
stone. The  limestone  ridge  south  of  Kent  has  rock  at  surface,  there  being 
scarcely  enough  drift  to  form  a  soil. 

The  following  table  of  wells  is  made  up  largely  from  data  furnished 
by  Mr.  Hershey: 

Table  of  well  sections  in  Stephenson  County,  Illinois. 


Owner  or  location. 


Altitude       T^...v*i, 
(above tide).    ^"P"^' 


Baier  &  Ohiendorf,  .at  Free- 
port. 

J.  Wareham,  Freeport 

D.  Hoover,  Freeport 

Millner'B  Brewery,  Freeport. .. 
Klectric  light  plant,  Freeport . 
Stover  M'fg  Co.,  of  Freejiort. . 

V^inegar  Works,  Freeport 

Triple  Factories,  Freeport 

H.  S.  Gochenour,  Freeport 

I ).  Sweeny,  East  Freeport 


Feet. 
765 


770 


(?) 


780 
760 
7.55 
750 
770 
825 
760 


Feet. 
240 

212 

60 

57 

240 

112 

(?) 

(?) 

80 

50 


Remarks. 


Enters  St.  Peter  sandstone  at  167  feet ;  drift,  34  feet. 

St.  Peter  sandstone  at  186  feet ;  drift,  85  feet. 
Depth  of  drift,  35  feet. 

Strong  vein  of  water  in  limestone ;  drift,  30  feet. 
Drift,  mainly  loess,  30  feet. 
Enters  St.  Peter  sandstone ;  drift,  100  feet. 
Penetrates  drift  85  feet. 
Drift,  mainly  loess,  38  feet. 
Rock  entered  at  6  feet. 

Wells  in   lOast  Freeport  30  to  50  feet  in  depth  do 
not  ivacl]  rock. 


WELLS  OF  STEPHENSON  COUNTY,  ILLINOIS. 

Table  of  well  sections  in  Stephenson  Comity,  Illinois — Continued. 


569 


Owner  or  location. 

Altitude 
(above  tide) . 

Depth. 

Hemarks. 

Sec.  23,  T.  27,  E.  9  E 

Feet. 
750 
765 

(?) 
900 
825 

(?) 
820 
840 
785 
800 
800 
790 
770 
770 
900 
840 
850 
850 
850 
785 
775 
775 
800 
850 
850 
850 
825 
800 
900 
850 
850 
819 
900 

Feet. 

30 

82 

65 

80 

72 

80 

150 

100 

60 

72 

100 

31 

45 

60 

80 

90 

100 

85 

90 

104 

110 

161 

100 

192 

248 

128 

165 

128 

186 

87 

142 

70 

70 

Rock  not  entered. 

Sec.  30,  T.  27,  R.  9  E 

W.  H.  Fulton,  Rock  Grove 

Enters  rock  at  62  feet. 
Rock  entered  at  20  feet. 
Drift  in  places,  80  feet. 
Enters  rock  a.t  10  fpet 

Sec.  25,  T.  27,  R.  8  E 

Sec.  17,  T.  27,  R.  7  E 

On  a  low  gravel  ridge. 
Enters  rock  at  fi  fftpt 

Sec.  29,  T.  27,  R.  8  E 

Sec.  31,  T.  27,  E.  6  E 

No  rock  entered. 

Sec.  7,  T.  26,  E.  7  E 

Sec.  12,  T.  26,  R.  7  E 

Enters  rock  at  20  ffipt 

Sec.  12,  T.  26,  R.  7  E 

Enters  rock  at  98  feet ;  drift,  gravelly. 
Enters  rock  at  10  feet. 
Enters  rock  at  3.5  feet 

NE.  i  sec.  7,  T.  26,  R.  8  E 

Sec.  7,  T.  26,  R.  8  E 

Sec.  17,  T.  26,  R.  8  E 

Sec.  6,  T.  26,  R.  7  E 

Sec.  13,  T.  26,  R.  7  E 

No  rock  entered ;  drift,  mainly  clay. 

No  rock  entered;  over  old  valley  of  Yellow  Creek. 

Entirely  fine  gravel  and  sand. 

No  rock;  drift  mainly  sand. 

Enters  rock  at  .50  ft^t^i 

Sec.  14,  T.  26,  R.  7  E 

Sec.  19,  T.  26,  R.  8  E 

Sec.  30,  T.  26,  R.  8  E 

Sec.  5,  T.  26,  R.  8  E    

Sec.  8,  T.  26,  R.  8  E 

Enters  rock  at  7fi  fppit. 

County  Infirmary 

Enters  rock  at  1^1  ft^R-t 

Sec.  13,  T.  26,  R.  7  E 

Enters  rock  nt  fil  fppf 

Sec.  12,  T.  26,  R.  7  E 

Sec.  14,  T.  26,  R.  7  E 

Enters  rock  at  175  feet. 
Enters  rock  at  183  feet;  drift,  blue  till. 
Enters  rock  at  115  feet ;  drift,  variable. 
Enters  rock  at  141  feet;  drift,  variable. 
Enters  rock  at  112  feet;  drift,  variable. 
Enters  rock  at  140  feet;  drift,  variable. 
Enters  rock  at  70  feet;  drift,  variable. 
Enters  rock  at  120  feet;  drift,  mainly  blue  till. 
Mainly  blue  clay;  rock  at  bottom. 
Clay, 25  feet;  remainder  sand  and  gravel;  rock  at 
bottom. 

Sec.  14,  T.  26,  E.  7  E 

Sec.  13,  T.  26,  E.  7  E 

Sec.24,T.26,  R.7  E 

Sec.  36,  T.  26,  R.  7  E 

Sec.  20,  T.  26,  E.  8  E 

Sec.  21,  T.  26,  E.  8  E 

Mr.  Bolton,  Bolton  Station 

Sec.  31,  T.  26,  E.  7  E 

WINNEBAGO  COUNTY. 
GENERAL    STATEMENT. 


Winnebago  County  is  situated  on  the  north  border  of  the  State  midway 
between  the  Mississippi  River  and  Lake  Michigan,  with  Rockford  as  its 
county  seat,  and  has  an  area  of  5.52  square  miles.      The  eastern  portion  of 


570 


THE  ILLINOIS  GLACIAL  LOBE. 


the  county  is  traversed  from  north  to  south  by  Rock  River,  the  northwestern 
portion  is  traversed  from  west  to  east  by  the  Pecatonica,  and  the  southeast- 
ern portion  from  east  to  west  by  the  Kishwaukee  River. 

The  portion  of  the  county  west  of  Rock  River  has  generally  a  thin 
coating  of  drift,  except  in  the  preglacial  valleys.  The  majority  of  wells  on 
the  uplands  enter  rock  at  less  than  20  feet.  There  are,  however,  occasional 
wells  located  probably  over  tributaries  of  the  preglacial  Rock-  or  Pecatonica 
which  penetrate  75  feet  or  more  of  drift  without  reaching  the  rock.  Excel- 
lent exposures  of  the  drift  may  be  seen  along  the  line  of  the  Illinois  Central 
Railway  between  Rockford  and  Freeport.  Like  the  drift  of  Stephenson 
County,  it  is  generally  very  stony  and  contains  a  considerable  amount  of 
gravel  and  sand.  Much  of  this  portion  of  the  county  is  covered  with  a 
loess-like  silt  4  or  5  feet  in  tliickness,  which  furnishes  an  excellent  soil. 

The  portion  of  the  county  east  from  Rock  River  can-ies  a  heavy 
deposit  of  drift,  rock  seldom  being  found  at  less  than  100  feet,  and  it  is 
probable  that  along  the  valley  of  Rock  River  and  its  immediate  borders  the 
thickness  exceeds  300  feet,  for  borings  to  the  north  and  south  show  that  the 
rock  floor  of  the  preglacial  valley  stands  250  to  300  feet  below  the  present 
stream  bed.  The  drift  of  the  eastern  portion  of  the  county  embraces  a 
sheet  which  extends  but  little  west  of  Rock  River  and  which,  as  indicated 
above,  is  referred  to  the  lowan  stage  of  glaciation. 

INDIVIDTJAL   WELLS. 

A  lai-ge  number  of  well  sections  were  collected  by  Mr.  I.  M.  Buell 
during  his  investigation  of  the  drumlins  and  bowlder  distribution  of  Winne- 
bago and  Boone  counties.  But  few  records  have  been  obtained  by  the 
wi-iter.  Mr.  Buell  has  kindly  turned  over  these  well  records  for  presenta- 
tion in  this  report,  and  they  appear  in  the  table  below.  They  are  chiefly 
found  in  the  disti*ict  east  of  Rock  River. 


Table  of  well  sections  east  of  Rock  River  in  Witmebago  County,  Illinois. 


Owner  or  location. 

Altitude. 

Depth. 

Kemarks. 

Ser,  14  T  46  R  2  E      

Feet. 
900 
850 
900 

Feet. 
60 
60 
65 

Largely  sandy  cUift;  iio  rock. 
Drift  till;  strikes  rook. 

Brow  of  bluft';  uo  rock;  gravel,  20  feet;  bine  clay, 
35  feet. 

WELLS  OF  WII^NEBAGO  COUNTY,  ILLINOIS.  571 

Table  of  tvell  sections  east  of  Bock  Kiver  in  Winnebago  County,  Illinois — Continued. 


Owner  or  location. 

Altitude. 

Depth. 

Eemarks. 

Feet. 

Feet. 

Sec.  15,  T.  46,  R.  2  E 

800 

65 

Till  with  gravel  at  bottom. 

750 

30 

Foot  of  blufif ;  drift  till;  no  rocli. 

Sec.  1,  T.  45,  R.  2  E 

925 

107 

Eock  entered  at  40  feet. 

900 

120 

Till,  65  feet;  gravel,  16  feet;   till,  10  feet;  sand,  30 
feet;  no  rock  struck. 

Sec.  2,  T.  45,  R.  2  E 

900 

75 

Mainly  till ;  upper  part  stony ;  rock  at  bottom. 
Bottom  of  well  in  gravel. 

900 

100 

900 

110 

Till,  75  feet ;  remainder  sand. 

Sec.  3,  T.  45,  R.  2  E 

900 

50 

Eock  at  50  feet  or  less. 

850 

180 

Eock  struck  at  65  feet. 

Sec.  4,  T.  45,  E.  2  E 

850 

100 

Brow  of  blufif;  till,  80  feet;  gravel,  20  feet ;  no  rock. 
Foot  of  blufif;   gravel  (partly  cemented),  46  feet; 

750 

55 

clay  and  sand,  9  feet;  no  rock. 

750 

65 

Rock  river  bottom;  till, 43  feet;  sand, 22  feet;  no 
rock  struck. 

Sec.  15,  T.  45,  R.  2  E 

850 

55 

In  o^ravel  at  bottom 

850 

60 

Rock  struck  at  57  feet. 

850 

60 

Gravel  at  bottom. 

Sec.  22,  T.  45,  R.  2  E 

825 

35 

Gravel  at  bottom 

Churcli  N.  of  Arffyle -. 

900 

50 

Sec.  32,  T.  45,  R.  2  E 

825 

45 

Brow  of  blufif;  gravel  at  bottom. 

Brow  of  bluff;  ferruginous  drift  conglomerate. 

No  rock ;  drift  gravelly. 

Entirely  till ;  no  rock. 

Sec.  5,  T.  44,  R.  2  E 

800 

28 

Sec.  8,  T.  44,  R.  2  E 

825 

32 

825 

90 

825 

50 

Till;  no  rock. 

825 

40 

Till  with  cemented  gravel  at  bottom. 

825 

90 

Sand  at  bottom. 

Sec.  17,  T.  44,  R.  2  E 

825 

60 

Dug  through  till ;  drilled  through  cemented  gravel ; 
loose  gravel  at  bottom. 

825 

140 

Till,  100  feet;    cemented  gravel,  40  feet;    no   rock 
struck. 

825 

140 

Similar  to  preceding,  and  40  rods  distant. 

Sec.  19,  T.  44,  R.  2  E 

825 

80 

Till,  74  feet;  gravel  at  bottom. 
No  rock ;  mainly  gravel. 
Similar  to  preceding. 

Sec.  20,  T.  44,  R.  2  E 

825 

50 

825 

45 

Sec.  32,  T.  44,  R.  2  E 

850 

103 

Wood  in  gravel  below  till  at  75  feet ;  no  rock  struck. 
Till,  40  feet;  sand  at  bottom. 

850 

107 

850 

98 

Sand  at  bottom. 

850 

46 

Eock  struck  at  45  feet. 

Sec.  7,  T.  44,  E.  2  E 

800 

75 

No  rock  struck;  much  ferruginous  drift  conglom- 
erate in  that  vicinity. 

Sec.  18,  T.  43,  R.  2  E 

775 

30 

Drift,  30  to  40  feet  in  that  vicinity. 

572  THE  ILLINOIS  GLACIAL  LOBE. 

Table  of  well  sections  east  of  Bock  River  in  Winnebago  County,  Illinois — Continued. 


Owner  or  location. 

Altitude. 

Deptt. 

Hem  arks. 

Feet. 

Feet. 

Sec.  30,  T.  43,  R.  2  E           

800 

40 

Mainly  till;  no  rock. 

Largely  gravel ;  rock  at  bottom. 

Across  road  from  preceding  . .. 

800 

40 

Sec.  34,  T.  43,  E.  2  E 

775 

95 

No  rock ;  mainly  till.    Hills  at  higher  levels  in 
vicinity  have  thin  drift. 

that 

James    Rested,   SE.    part    of 

775 

100 

Drift,  mainly  till ;  rock  struck. 

county. 

Mr.  Davis,  SE.  part  of  county. . 

775 

60 

Drift  ranges  from  10  to  60  feet  on  the  farm. 

Mr.  Watson,  SE.  part  of  county 

800 

90 

No  rock  struck. 

W.  E.  Corlett,  S.  of  New  Mil- 

775 

140 

Bluff  of  Kishwaukee;  no  rock  struck;  quarries  at 

ford. 

a  higher  point  toward  the  east. 

Sec.  25,  T.  43,  E.  1  E 

800 

55 

On  gravel  knoll :  no  rock. 

The  waterworks  station  at  Rockford  is  located  near  the  base  of  the 
west  bluff  of  Rock  River  Valley  in  the  north  part  of  the  city.  Five  wells 
are  sunk  to  the  Potsdam  sandstone,  from  which  water  rises  barely  to  the 
surface  (719  feet  above  tide).  With  a  diameter  of  6  inches,  each  well  fur- 
nishes about  200  gallons  per  minute  by  pumping.  The  drift  ranges  from 
125  to  190  feet  in  depth.  The  upper  portion  is  sand  and  gravel,  but  the 
lower  portion  is  largely  blue  clay.  No  wells  have  been  sunk  in  the  midst 
of  the  valley  at  Rockford  of  sufficient  depth  to  reach  the  rock.  The  distance 
to  rock  is  probably  much  greater  than  in  the  wells  at  the  waterworks.^ 

At  Pecatonica  wells  usually  obtain  water  in  the  limestone  at  depths  of 
80  to  125  feet.  The  drift  in  that  vicinity  is  but  a  few  feet  in  depth.  The 
waterworks  is  supplied  from  springs. 

.  In  the  vicinity  of  Winnebago  Village  the  distance  to  rock  ranges  from 
20  to  at  least  80  feet.  Wells  are  usually  obtained  without  entering  rock, 
though  several  have  been  sunk  some  distance  into  the  rock. 

In  the  vicinity  of  Elida  the  drift  is  usually  about  50  feet,  and  a  few 
wells  pass  into  the  underlying  limestone.  West  from  Elida  and  also  north- 
west, over  an  area  of  perhaps  50  square  miles,  wells  usually  obtain  water  in 
the  rock  at  depths  ranging  from  40  to  100  feet.  The  drift  in  that  locality  is 
thin,  seldom  exceeding  20  feet.  Mr.  Buell,  however,  reports  two  wells  in 
sec.  3,  T.  26,  R.  10  PI,  50  and  60  feet  in  depth,  which  do  not  strike  rock. 
Another  well  in  the  same  section,  enters  rock  at  40  feet  and  is  cairied  to  a 
depth  of  110  feet.     Still  another  well  located  on  a  di'ift  knoll  enters  rock  at 

'The  data  from  Eockford  have  been  lurnished  by  Daniel  W.  Mead,  C.  E.,  of  that  city. 


WELLS  OF  BOONE  COUNTY,  ILLINOIS.  573 

30  feet.  In  the  neig-liboriug  section  on  the  north  there  are  several  outcrops 
of  limestone,  though  one  well  in  that  section  fails  to  reach  rock  at  106  feet. 
A  well  in  sec.  1,  T.  26,  R.  10,  114  feet  in  depth,  enters  rock  at  50  feet. 

In  the  northwestern  one-fourth  of  the  county  rock  is  usually  entered  at 
slight  depth  except  in  a  narrow  belt  along  the  Pecatonica  and  Sugar  rivers. 
But  here,  as  in  the  southwestern  portion  of  the  county,  occasional  wells  on 
the  iipland  reach  a  depth  of  80  feet  or  more  before  entering  rock. 

BOONE    COUNTY. 
GENERAL    STATEMENT. 

Boone  County  is  situated  immediately  eas't  of  Winnebago  County,  on 
the  north  border  of  the  State,  and  has  an  area  of  but  290  square  miles. 
Behddere,  the  county  seat,  is  situated  near  the  southern  edge  of  the  county_ 
It  is  drained  chiefly  by  the  Kishwaukee  and  its  tributaries,  which  occtipy 
gravel  plains  leading  westward  from'  the  moraines  of  the  "Wisconsin  drift 
sheet  in  McHenry  County.  These  gravel  plains  are  in  places  a  mile  or 
more  in  width  and  afli'ord  an  abundance  of  water  at  shallow  depth,  wells 
seldom  exceeding  25  feet. 

The  di'ift  is  thinnest  in  the  southern  portion  of  the  county,  there  being 
numerous  quarries  in  the  two  townships  on  its  south  border.  In  the  north- 
ern part  of  the  county  the  drift  is  probably  not  less  than  75  feet  in  average 
depth,  and  it  may  possibly  be  as  deep  as  in  the  neighboring  portion  of 
Winnebago  County,  from  which  the  list  of  wells  in  the  above  table  was 
prepared.  Water  is  usually  obtained  at  depths  of  30  or  40  feet  in  that 
portion  of  the  county  from  beds  of  gravel  or  sand  associated  with  the  till, 
the  greater  part  of  the  drift  being  a  typical  till.  In  this  county  the  glacial 
drift  with  its  bowlders  is  not  covered  by  deposits  of  loess  or  other  silt  as  in 
counties  to  the  west,  and  the  surface  sheet  of  drift,  like  that  of  eastern 
Winnebago  County,  is  referred  to  the  lowan  stage  of  glaciation. 

INDIVIDUAL    WELLS. 

The  city  of  Belvidere  obtains  its  public  water  supply  from  a  well 
sunk  to  a  depth  of  1,950  feet.  The  well  is  cased  only  to  the  limestone, 
58  feet,  and  water  is  found  at  several  horizons  above  the  Potsdam  (in  which 
the  well  terminates)  as  well  as  in  that  formation.  The  head  is  but  6  feet 
below  the  well  mouth,  or  757  feet  above  tide.  Though  only  4  inches  in 
diameter  in  its  lower  portion,  it  is  found  to  have  a  capacity  of  400  gallons 
per  minute.     The  hardness  of  the  water  suggests  that  it  is  largel}'  derived 


574  THE  ILLINOIS  GLACIAL  LOBE. 

from  limestone.  The  jjrivate  wells  in  this  city  usually  obtain  water  from 
gi-avel  at  a  depth  of  about  20  feet.  A  few  in  the  south  part  of  the  city, 
outside  the  limits  of  the  Kishwaukee  gravel  plain,  are  sunk  to  greater  depth, 
but  seldom  exceeding  40  feet. 

At  the  village  of  Caledonia,  wells  usually  obtain  water  from  beds  of 
gravel  beneath  till  at  a  depth  of  30  or  40  feet.  The  following  table  of  wells 
on  farms  in  the  neighborhood  of  Caledonia  will  serve  to  illusfrate  the  varia- 
tions in  depth  in  the  northern  part  of  the  county.  It  will  be  noted  that 
only  two  of  these  wells  enter  the  rock,  viz,  those  in  sec.  30,  T.  46,  R.  3  E., 
and  sec.  7,  T.  45,  R.  3  E.      . 

Depth  of  rcells  in  northern  Boone  County. 

Peet. 

John  Van  Aiithrop,  sec.  34,  T.  46,  R.  4  E  42 

William  Millard,  sec.  35,  T.  46,  R.  4  E  34 

William  Smith,  sec.  26,  T.  46,  R.  4  E 63 

James  Hinemau,  sec.  26,  T.  46,  R.  4  E 60 

Sec.  30,  T.  46,  R.  3  E.  (rock  at  50  feet) 150 

Sec.  7,  T.  45,  E.  3  E.  (rock  at  54  feet) 110 

Sec.4,T.45,  E.3E.  (several  wells) 30-40 

D.  S.  Kelly,  sec.  3,  T.  45,  R.  3  E 35 

J.  F.  Ramsey,  sec.  3,  T.  4,5,  R.  3  E 30 

John  Church,  sec.  2,  T.  45,  R.  3  E 35 

E.  F.  Bailey,  sec.  1,  T.  45,  R.  3  E 21 

Philip  Colieman ,  sec.  6,  T.  45,  R.  4  E :  -  24 

Peter  Mclntyre,  sec.  6,  T.  45,  R.  4  E 25 

Peter  Oleson,  sec.  5,  T.  45,  R.  4  E 22 

John  Stall,  sec.  4,  T.  45,  R.  4  E 76 

J.  Miller,  sec.  3,  T.  45,  R.  4  E 63 

Die  Nelson,  sec.  3,  T.  45,  R.  4  E 65 

T.  L.  Bowman,  eec.  3,  T.  45,  R.  4  E 48 

Herbert  Young,  sec.  3,  T.  45,  R.  4  E 35 

In  Bonus  Township,  situated  northeast  from  Belvidere,  the  wells  on 
the  upland  between  the  Kishwaukee  River  and  Piscasaw  Creek  in  several 
instances  reach  a  depth  of  about  60  feet  without  entering  rock. 

Although  rock  is  usually  struck  at  comparatively  slight  depth  in  the 
southeast  township  (T.  43,  R.  4  E.),  a  well  at  a  cheese  factory  in  sec.  15 
did  not  reach  rock  at  a  depth  of  83  feet.  Several  wells  in  sees.  8,  9,  16, 
and  17  of  this  township  enter  rock  at  depths  ranging  from  4  feet  to  20  feet 
on  an  upland  standing  about  900  feet  above  tide.  On  Coon  Creek  gravel 
plain,  in  sec.  3  of  this  township,  at  an  elevation  less  than  800  feet  above 
tide,  a  well  45  feet  in  depth  does  not  reach  rock.  A  well  at  Mr.  Rj^an's,  in 
sec.  33,  at  an  elevation  about  775  feet  above  tide,  is  86  feet  in  depth  and 
.strikes  rock  at  33  feet.  Wells  in  sec.  23  reach  a  depth  of  30  or  40  feet 
without  entering  rock. 


WELLS  OP  McHElSrEY  COUNTY,  ILLINOIS.  575 

In  the  soutliwest  township  of  the  connty,  in  the  vicinity  of  Irene,  wells 
are  usually  sunk  into  the  rock,  thoug-h  the  di'ift  in  places  exceeds  30  feet. 
The  Illinois  Central  Railway  cutting-,  immediately  west  of  Irene,  shows  an 
extensive  exposure  of  black  soil  containing  moUuscan  shells  underneath  a 
sheet  of  till.  The  soil  appears  to  separate  the  lowan  till  sheet  from  the 
lUinoian  in  which  case  it  is  referable  to  the  Sangamon  interglacial  stage. 

McHENRY  COUNTY. 
GENERAX,   STATBJEENT. 

McHenry  County  is  situated  immediately  east  of  Boone,  on  the  north 
border  of  the  State,  Woodstock  being  its  county  seat,  and  has  an  area  of 
624  square  miles.  Its  western  portion  is  di-ained  by  the  Kishwaukee  and 
tributaries  westward  to  Rock  River,  while  the  eastern  portion  is  drained 
southward  through  Fox  River,  which  has  its  course  near  the  eastern  border 
of  the  county  through  a  series  of  lakes  and  sloughs.  This  is  one  of  the 
■  most  elevated  counties  in  the  State,  several  square  miles  on  its  northern 
border  being  above  the  1,000-foot  contour,  while  much  of  the  county 
stands  above  900  feet. 

The  greater  part  of  the  county  is  occupied  by  a  system  of  moraines 
fonned  at  the  Wisconsin  stage  of  glaciation,  there  being  only  a  naiTOw 
sb-'ip  on  the  western  border  of  the  county,  scarcely  a  township  in  average 
width,  which  lies  outside  its  outer  morainic  system.  This  is  underlaid 
largely  by  a  gravel  overwash  from  the  moraine,  and  is  therefore  of  Wisconsin 
age.  There  are  a  few  outcrops  of  rock  near  the  Kishwaukee  in  the  western 
portion  of  the  county  at  an  altitude  about  800  feet  above  tide,  but  these 
appear  to  stand  above  the  general  level  of  the  rock  surface  and  represent 
probably  the  tops  of  j^reglacial  ridges  or  hills.  Several  deep  wells  scattered 
widely  over  the  coimty  have  shown  the  presence  of  a  very  thick  deposit  of 
drift.  It  is  probable  that  the  average  depth  is  not  less  than  200  feet,  or 
nearly  twice  the  average  depth  of  drift  for  the  State. 

The  wells  for  household  use  usually  obtain  water  at  moderate  depth 
(20  or  30  feet),  but  wells  for  stock  are  often  siink  to  depths  of  100  or  even 
200  feet.  Dairying  being  one  of  the  principal  industries  of  the  county,  a 
large  number  of  farmers  have  sunk  deep  wells  to  supply  their  cattle.  The 
records  of  only  a  few  of  these  were  obtained,  but  they  are  thought  to  be 
representative. 


576  THE  ILLINOIS  GLACIAL  LOBE. 

INDIVIDUAL    WELLS. 

The  northwestern  township  of  the  county  (Chemung)  is  occupied 
chiefly  by  a  gravel  plain,  in  which  wells  are  obtained  at  a  depth  of  25  to  35 
feet.  In  the  vicinity  of  Chemung,  however,  the  wells  encounter  till,  and 
their  depth  ranges  from  20  feet  to  70  or  more,  water  being  obtained  in  beds 
of  o-ravel  associated  with  the  till. 

The  railway  well  at  Harvard,  in  the  southeast  part  of  Chemung  Town- 
ship, is  sunk  to  a  depth  of  900  feet,  and  is  thought  to  terminate  in  the  lower 
portion  of  the  St.  Peter  sandstone.     The  following  strata  were  penetrated : 

Section  of  the  railway  well  at  Harvard,  Illinois. 

Peet. 

Yellow  and  blue  till 36 

Gravel  and  bowlders - 24 

Sand  and  loose  gravel 15 

Coarse  gravel 1^ 

"Hardpan" 12 

Limestone ^^° 

Shale 85 

Mainly  limestone 3*5 

Mainly  sandstone -^^ 

The  water  is  hard  and  is  apparently  largely  derived  from  the  limestone. 
It  rises  within  41  feet  of  the  surface,  or  to  an  altitude  894  feet  above  tide. 
The  well  is  cased  only  to  the  rock  (102  feet),  and  has  a  diameter  of  7  inches 
below  the  casing.  The  capacity  is  estimated  at  90  gallons  per  minute. 
Many  private  wells  are  obtained  in  Harvard  at  a  depth  of  about  25  feet. 
The  west  part  of  the  village  is  on  a  gravel  plain,  with  a  sheet  of  water  at 
20  to  25  feet  or  less.  The  railway  station  and  east  part  of  the  village  stand 
on  the  slope  of  a  moraine. 

In  the  township  east  of  Chemung  only  one  well  record  was  obtained — 
that  at  the  cheese  factory  in  the  village  of  Alden.  This  well  reached  a  depth 
of  150  feet  without  entering  rock,  and  has  the  following  section: 

Section  of  well  at  a  cheese  factory  in  Alden,  Illinois. 

reet. 

Gravel  and  sand 1" 

Blue  till ^"0 

Black  soil 

Till  of  bluish  color 33 

It  is  probable  that  the  soil  struck  at  the  base  of  the  blue  till  marks 
either  the  junction  between  the  "Wisconsin  drift  sheet  and  the  lowan,  or 
between  the  lowan  and  Illinoian.     The  well  is  on  a  moraine. 


WELLS  OP  McHENEY  COUXTY,  ILLmOIS.  577 

In  the  vicinity  of  English  Prairie  post-office,  in  the  northeast  part  of 
the  county,  there  is  an  extensive  gravel  plain  standing  at  an  elevation 
slightly  above  800  feet,  in  which  occasional  wells  have  been  sunk  to  a  depth 
of  150  feet  without  reaching  rock,  mainly  tlu-ough  gravel. 

At  Woodstock,  the  county  seat,  a  boring  was  made  some  years  ago 
which  struck  a  black  soil  at  about  160  feet,  beneath  which  was  till,  in  which 
the  well  terminated  at  a  depth  of  180  feet.  This  soil,  like  that  at  Alden, 
probably  marks  the  junction  between  the  Wisconsin  and  lowan  drift  sheet, 
or  possibly  between  the  lowan  and  Illinoian.  A  well  has  been  sunk  in  Wood- 
stock to  a  depth  of  1,014  feet,  but  no  accurate  record  of  the  strata  penetrated 
appears  to  have  been  kept.  The  drift  has  a  thickness  of  230  feet.  The  well 
is  said  to  terminate  in  sandstone,  probably  St.  Peter.  A  water-bearing  "sand 
rock"  was  entered  at  825  feet.  The  water  is  reported  to  be  soft  and  of  a 
pleasant  taste,  and  has  a  capacity  of  150  gallons  per  minute  from  a  j)ipe  6^ 
inches  in  diameter.  The  head  is  60  feet  below  the  surface.  Many  private 
wells  in  Woodstock  and  vicinity  obtain  water  at  depths  ranging  from  20  to  60 
feet.     They  are  mainly  through  till,  though  beds  of  sand  and  gravel  occur. 

At  Marengo  the  wells  vary  greatly  in  depth,  those  on  the  gravel 
plain  along  the  Kishwaukee  being  but  20  to  25  feet,  while  those  on  the  slope 
of  the  moraine  in  the  south  part  of  the  city  are  often  60  to  80  feet,  and 
occasionally  125  feet  or  more.  So  far  as  ascertained,  no  wells  reach  the 
rock.  The  drift  is  largely  of  gravelly  constitution.  A  well  belonging  to 
Mr.  P.  T.  Parkhurst,  100  feet  in  depth,  penetrated  a  black  muck  at  about 
60  feet,  from  which  inflammable  gas  issued.  This  muck  probably  underlies 
the  Wisconsin  drift  sheet.  A  similar  muck  was  struck  on  the  farm  of  James 
Smith,  3  miles  northwest  of  Marengo,  at  a  depth  of  only  28  to  30  feet.  The 
well  stands  on  the  slope  of  the  outer  moraine  of  the  Wisconsin  drift,  slightly 
above  the  level  of  the  older  sheet  of  drift  to  the  west.  The  soil  in  all  prob- 
ability is  at  the  base  of  the  Wisconsin  drift  and  above  the  lowan  di'ift.  At 
a  cheese  factory  south  of  Marengo,  in  sec.  11,  T.  43,  R.  5  E.,  a  well  struck 
a  black  muck  beneath  blue  till  at  a  depth  of  70  feet.  As  the  well  is 
situated  on  the  moraine  at  about  70  feet  above  the  lowan  drift  plain  to  the 
west,  the  soil  probably  caps  lowan  drift. 

At  the  village  of  Crystal  Lake  wells  usually  obtain  water  at  depths  of 
50  to  70  feet  and  are  largely  through  gravel.  A  well  about  4  miles  south- 
west of  this  village,  in  sec.  12,  T.  43,  R.  7  E.,  reached  a  depth  of  210  feet 

MON   XXXVIII 37 


578  THE  ILLINOIS  GLACIAL  LOBE. 

without  entering  rock.  Water  is  obtained  in  gi-avel  near  the  bottom,  the 
greater  part  of  the  well  section  being  till. 

In  the  vicinity  of  Cary  wells  are  60  to  100  feet  in  depth.  Thej^ 
usually  penetrate  about  50  feet  of  dry  gravel,  beneath  which  is  till,  having 
water-bearing  beds  associated  with  it. 

At  Algonquin,  in  the  southeast  corner  of  the  county,  an  artesian  well 
was  sunk  to  a  depth  of  2,527  feet  by  the  Illinois  Condensing  Company. 
Rock  is  struck  at  about  100  feet,  and  the  well  probably  terminates  in  Pots- 
dam sandstone.  At  last  reports  the  use  of  the  well  had  been  discontinued 
because  of  the  corrosion  of  the  pipes  by  the  water.  The  public  water  sup- 
ply for  this  village  is  from  springs.  Many  wells  on  the  low  ground  obtain 
water  at  about  12  feet.  A  few  have  been  bored  to  depths  of  60  or  80  feet. 
They  enter  till  after  penetrating  12  to  20  feet  of  gravel.  Occasional  flow- 
ing wells  are  obtained  in  this  vicinity.  One  in  the  valley  of  Crystal  Lake 
outlet,  about  a  half  mile  above  Algonquin,  has  a  depth  of  60  feet.  One  at 
a  blacksmith  shop  in  the  north  part  of  Algonquin  is  62  feet  in  depth,  and 
has  a  head  14  feet  above  the  surface.  The  bordering  uplands  rise  to  a  height 
of  aboutlOO  feet  above  the  level  of  the  wells,  and  thus  furnish  an  absorb- 
ing area  of  sufficient  height  to  give  a  strong  hydrostatic  pressure. 

At  South  Riley,  in  the  southwest  part  of  the  county,  rock  is  usually 
entered  below  blue  till  at  a  depth  of  about  60  feet,  or  at  an  elevation  not 
far  from  800  feet  above  tide.  Rock  is  also  struck  in  several  wells  on  the 
plain  northwest  from  Marengo,  in  the  southwest  part  of  T.  45,  R.  5  E.,  and 
northwest  part  of  T.  44,  R.  5  E.,  at  a  depth  of  about  60  feet.  The  general 
elevation  of  the  region  is  about  850  feet  above  tide.  A  short  distance  east 
from  these  wells,  however,  a  well  on  the  farm  of  Mr.  Alsing,  sec.  35,  T.  45, 
R.  5  E.,  reached  a  depth  of  100  feet  without  entering  rock. 

The  following  sections  of  farm  wells  are  of  interest  because  of  their 
depth.  They  are  located  on  or  among  the  moraines  of  the  Wisconsin  drift 
sheet  and  none  of  them  reach  the  rock: 

Deep  drift  boringn  in  xoutheastern  McHenry  Co  Kitty. 

Feet. 

Moses  Dinion,  2  miles  south  of  Mareugo 123 

K.  Cooney,  sec.  14,  T.  45,  E.  6  E 94 

Harmony  post-olBce 112 

IraCnrtiss,  near  center  of  T.  43,  R.  6  E 180 

Well  80  rods  east  of  preceding 86 

W.  Whitteinoie,  T.  43,  K.7  E  ..; .■ 100 

Mr.  C^unuuings,  near  Hnntley 108 

George  Bunker,  T.  44,  Iv.  7  E 84 


WELLS  OF  LAKE  COUNTY,  ILLINOIS.  579 

The  well  at  Mr.  Cummings's  overflows,  although  at  an  altitude  about 
900  feet  above  tide,  and  that  at  Mr.  Whittemore's  rises  nearly  to  the  sur- 
face. The  absorbing  area  is  probably  on  a  moraine  south  of  the  wells, 
which  rises  to  a  higher  elevation  than  that  of  the  well  sites.  All  the  wells 
in  the  above  list  are  mainly  through  till.  In  this  connection  it  may  be 
remarked  that  the  moraines  of  this  county  appear  to  be  composed  chiefly  of 
till,  the  principal  exception  being  a  gravelly  area  occupying  a  few  square 
miles  in  the  vicinity  of  Crystal  Lake  and  thence  eastward  to  Fox  River. 

LAKE    COUNTY. 
GENERAL    STATEMENT. 

Lake  County  is  situated  in  the  extreme  northeast  comer  of  the  State,  on 
the  border  of  Lake  Michigan.  It  has  an  area  of  490  square  miles,  and  the 
county  seat  is  Waukegan.  The  eastern  portion  of  the  county  is  traversed 
from  north  to  south  by  the  Des  Plaines  River,  while  the  western  portion 
is  touched  by  Fox  River.  There  are  numerous  lakes  in  the  western  half 
of  the  county,  situated  among  the  knolls  and  ridges  of  the  Valparaiso 
morainic  system.  There  are  also  extensive  marshes  and  sloughs  bordering 
these  lakes  and  Fox  River.  The  Valparaiso  morainic  system,  which  occu- 
pies much  of  the  western  half  of  the  county,  stands  200  to  300  feet  above 
Lake  Michigan.  Other  moraines,  occupying  a  narrow  belt  between  the  Des 
Plaines  and  Lake  Michigan,  stand  100  feet  or  more  above  the  lake. 

The  drift  of  this  county  probably  has  an  average  thickness  of  more 
than  200  feet.  The  few  wells  which  enter  rock  find  a  rock  surface  lower 
than  the  level  of  Lake  Michigan,  and  several  other  deep  borings  penetrate 
below  the  level  of  Lake  Michigan  without  entering  rock.  It  is  scarcely 
probable  that  the  rock  surface  will  average  an  elevation  as  great  as  the 
level  of  the  lake  (580  feet  above  tide).  The  upper  portion  of  the  drift,  to 
a  depth  of  about  150  feet,  is  chiefly  a  soft  blue  till,  thought  to  be  of  Wis- 
consin age.  Beneath  this  occasional  borings  in  Lake,  as  in  neighboring 
counties  on  the  south  and  west,  enter  a  hard  till,  thought  to  belong  to  the 
earlier  stages  of  glaciation. 

The  wells  in  this  county  usually  obtain  water  at  moderate  depths,  from 
gravel  or  sand  associated  with  the  till.  Such  wells,  however,  are  often 
weak,  and  farmers  have  occasionally  sunk  to  depths  of  200  feet  or  more  in 
order  to  obtain  a  larger  supply. 


580  THE  ILLINOIS  GLACIAL  LOBE. 


INDIVIDUAL   "WELLS. 


At  Waukegan  the  public  water  supply  was  formerly  obtained  from 
artesian  wells,  but  since  1895  it  has  been  obtained  by  pumping  from  Lake 
Michigan.  Three  wells  were  sunk  to  depths  of  1,135,  1,600,  and  2,005 
feet,  respectively.  The  tu-st  well  is  reported  by  Mayor  De  Wolf  to  have 
obtained  water  of  fair  quality,  though  rather  heavily  charged  with  iron. 
The  second  well  obtained  an  unpleasant  water  with  bad  odor,  thought  to 
be  sulphurous.  The  wells  were  discontinued  because  of  the  hardness  of 
the  water,  it  being  unfit  for  boiler  use.  The  water  also  was  found  unsuit- 
able for  sprinkling  lawns,  it  being  destructive  to  grass.  The  Lake  Michigan 
water  is  not  too  hard  for  boiler  use  and  in  other  ways  is  more  satisfactory 
than  the  artesian  water.  The  present  intake  is  at  a  distance  of  1,700  feet 
from  the  shore,  but  it  is  proposed  to  extend  the  tunnel  to  a  distance  of 
about  a  mile. 

At  Lake  Forest,  wells  which  will  yield  30  barrels  per  day  are  usually 
obtained  at  a  depth  of  40  feet  or  less.  An  artesian  well  at  the  residence 
of  Hon.  C.  B.  Farwell  reached  a  depth  of  960  feet  and  obtained  a  flow  of 
water  whose  head  was  originally  50  feet  above  the  surface,  or  about  125 
feet  above  Lake  Michigan.  The  drift  at  this  well  has  a  thickness  of  160 
feet. 

At  Highland  Park  there  are  four  artesian  wells  with  depths  of  1,800  to 
2,200  feet.  Mr.  P.  T.  Dooley,  a  well  driller,  residing  at  this  village,  reports 
that  wells  5  inches  in  diameter  yield  about  150  gallons  per  minute.  A 
strong  flow  of  water  is  obtained  at  about  900  feet  and  also  at  about  1,300 
feet,  as  well  as  at  lower  horizons.  The  wells  all  flowed  when  first  made, 
but  at  present  scarcely  reach  the  surface.  The  elevation  of  the  well  mouths 
is  110  to  115  feet  above  Lake  Michigan,  or  690  to  695  feet  above  the  sea. 
The  thickness  of  the  drift  is  about  175  feet. 

At  Milburn,  in  the  north  part  of  the  county,  on  a  plain  between  the 
Valparaiso  moraine  and  Des  Plaines  River,  several  flowing  wells  have  been 
obtained,  and  the  wells  on  this  plain  usually  show  marked  hydrostatic 
pressure.  In  some  cases  they  are  but  20  feet  in  depth,  and  rarely  exceed 
75  feet. 

Near  Wauconda,  in  the  western  part  of  the  county,  several  wells 
reach  a  depth  of  70  or  80  feet,  though  shallower  wells  are  common. 


WELLS  OF  LAKE  AND  COOK  COUNTIES,  ILLINOIS.  581 

Near  Lake  Zurich,  in  the  southwestern  part  of  the  count  j,  a  few  wells 
have  been  sunk  to  depths  of  over  200  feet  without  entering  rock.  One  in 
the  village  of  Lake  Zurich  reached  a  depth  of  240  feet;  one  on  the  Fletcher 
farm  in  sec.  32,  a  depth  of  230  feet,  and  one  about  a  mile  east  of  the  village 
reached  a  depth  of  297  feet.     The  latter  has  the  following  section : 

Section  of  loell  near  Lake  Zurich^  Illinois. 

Feet. 

Yellow  till 12 

Blue  till -- 88 

Fine  sand 197 

Total '. 297 

Gravel  at  bottom. 

A  well  driller  states  that  much  sand  is  found  at  de23ths  of  100  feet  or 
more  beneath  the  crest  of  the  Valparaiso  moraine  in  the  vicinity  of  Lake 
Zurich. 

At  Barrington,  on  the  south  line  of  the  county,  two  wells  enter  rock 
at  254  and  258  feet,  respectively.  They  encounter  considerable  coarse 
gravel  and  cobble  at  about  160  feet  The  remainder  of  the  section  is  mainly 
till.  It  is  thought  that  this  cobble  bed  occupies  the  junction  between  the 
Wisconsin  and  earlier  sheets  of  drift,  there  being  a  change  to  a  harder  till 
beneath  it. 

At  Hainesville,  in  the  north  central  part  of  the  county,  good  wells  are 
usually  obtained  at  80  or  90  feet,  but  one  boring  is  reported  to  have  reached 
a  depth  of  287  feet  without  obtaining  water  or  entering  rock.  Another 
unsuccessful  boring  is  reported  to  have  been  made  at  Grilmer,  in  the  south 
central  part  of  the  county.  It  reached  a  depth  of  213  feet  without  entering 
rock.  At  Deans  Corners  rock  was  struck  at  290  feet.  At  Ravinia,  in  the 
southeast  corner  of  the  county,  a  well  186  feet  in  depth  entered  rock  at 
164  feet. 

COOK    COUNTY. 
GENERAL    STATEMENT. 

Cook  County,  of  which  Chicago  is  the  county  seat,  has  a  wide  frontage 
on  Lake  Michigan  and  extends  back  to  distances  of  15  to  30  miles  from 
the  lake,  there  being'  much  irregularity  in  the  western  border.  It  is  one  of 
the  largest  counties  of  the  State,  the  area  being  960  square  miles.  The 
Chicago  River,  whose  main  branch  heads  near  the  north  line,  flows  south- 
ward near  the  eastern  edge  of  the  county  and  enters  the  lake  through  the 


582  THE  ILLINOIS  GLACIAL  LOBE. 

midst  of  the  city  of  Chicago.  Calumet  River  enters  the  county  from 
Indiana,  and  after  running  westward  to  Blue  Island,  a  distance  of  about 
12  miles,  it  turns  abi-uptly  eastward.  As  previously  noted,  it  formerly 
returned  into  Indiana  and  discharged  at  the  head  of  the  lake,  but  the 
present  mouth  of  the  river  is  at  Soutli  Chicago,  in  Illinois.  The  Des 
Plaines  River  flows  southward  from  the  north  line  of  the  county  to  Summit, 
having-  an  averagre  distance  of  about  10  miles  from  the  lake.  It  there  turns  " 
southwestward,  leaving  the  county  near  the  village  of  Lemont.  The 
extreme  northwestern  portion  of  the  county  is  tributary  to  Fox  River. 
Drainage  lines  are  poorly  developed  in  both  the  elevated  and  the  low-lying 
portions  of  the  county,  a  feature  which  is  characteristic  of  several  counties 
in  northeastern  Illinois. 

The  eastern  portion  of  the  county  is  a  plain  rising  gradually  westward 
to  the  borders  of  the  Valparaiso  morainic  system.  A  large  part  of  this  plain 
stands  only  10  or  15  feet  above  Lake  Michigan,  but  on  the  western  border 
its  elevation  is  40  to  60  feet  or  more.  The  plain  is  inteiTupted  by  a  small 
drift  ridge  leading  north  a  few  miles  from  Blue  Island.  There  are  also 
drift  ridges  near  the  border  of  Lake  Michigan,  in  the  north  part  of  the 
county,  which  rise  to  a  height  of  75  or  100  feet  above  the  lake.  The  \)oy- 
tion  of  the  plain  standing  within  60  feet  of  lake  level,  as  already  noted, 
has  been  occupied  by  Lake  Chicago,  whose  discharge  was  southwestward 
through  the  "Chicago  Outlet." 

The  Valparaiso  morainic  system  passes  across  the  northwestern  part  of 
Cook  County  in  a  southward  course,  and,  after  crossing  Dupage  County, 
again  enters  Cook,  occupying  the  southwestern  borders  of  the  county. 
This  system  stands  in  its  higher  parts  fully  200  feet  above  the  lake,  and  a 
small  area  in  the  extreme  northwest  part  of  the  county  reaches  an  elevation 
more  than  300  feet  above  the  lake. 

The  drift  is  comparatively  thin  on  much  of  the  plain  in  Chicago  and 
to  the  south  and  also  along  the  Chicago  Outlet,  rock  quarries  being  numer- 
ous and  many  instances  of  wells  encountering  rock  at  slight  depth  being 
found.  There  are,  however,  occasional  wells  which  reach  a  level  100  feet 
or  more  below  Lake  Michigan  before  encountering  rock.  The  available 
data  seem  to  indicate  that  a  buried  valley  enters  the  lake  near  Lincoln 
Park,  whose,  course  can  be  followed  for  several  miles  back  from  the   lake 


WELLS  OF  COOK  COUNTY,  ILLINOIS.  583 

in  a  westward  direction.     Wells  along  this  valley  reach  a  level  115  to  125 
feet  below  the  lake  before  encountering  rock.^ 

In  the  northern  part  of  the  county  the  rock  surface  appears  to  be  gen- 
erally lower  than  in  the  southern,  though  the  di-ift  surface  is  higher.  The 
thickness  of  drift  is  found  to  be  in  places  250  or  even  300  feet,  wliile  the 
average  probably  exceeds  200  feet.  Well  sections  reaching  the  rock  have 
been  obtained  in  all  parts  of  the  county  at  frequent  intervals,  except  in 
the  portion  occupied  by  the  Valparaiso  moraine  on  the  southwest  border, 
or  in  about  800  square  miles  of  the  960  embraced  in  the  county.  Sixty-two 
wells  are  found  to  show  an  average  of  83  feet  to  rock,  while  47  fail  to  enter 
rock  at  an  average  depth  of  79  feet.  The  drift  is  largely  a  compact 
till,  except  in  the  northwest  part  of  the  county,  where  thick  deposits  of 
sand  and  gravel  are  frequently  found  beneath  a  sheet  of  blue  till.  Beds  of 
sand  or  gravel  are,  however,  associated  with  the  till  in  sufficient  amount  to 
furnish  a  fair  supply  of  water  for  wells.  In  a  few  instances  wells  in  the 
northwest  part  of  the  county  have  penetrated  a  black  soil  below  till  at 
depths  in  some  cases  of  over  100  feet.  It  is  thought  that  the  drift  above 
such  soils  should  be  referred  chiefly  to  the  Wisconsin  stage  of  glaciation. 
The  soil  may,  however,  in  some  instances  be  found  below  the  lowan  drift. 

INDIVIDUAL    WELLS. 

In  the  city  of  Chicago  several  sources  have  been  drawn  upon  for  wells, 
but  the  public  water  supply  is  pumped  from  Lake  Michigan.  Since  the  drift 
is  generally  thin,  there  are  onl}^  small  areas  where  wells  or  rather  where 
pure  water  may  be  obtained  above  the  rock.  The  north  part  of  the  city, 
however,  obtained  water  from  the  drift  in  the  early  days  of  settlement. 
The  danger  of  contamination  of  such  wells  by  sewage  or  otherwise  is  so 
great  that  their  use  is  largely  discontinued. 

The  Lockport  (Niagara)  limestone,  which  underlies  the  city,  has  been 
drawn  upon  for  water  from  the  early  days  of  settlement,  but  the  use  of  water 
from  this  source  is  decreasing,  in  part  because  of  danger  from  contamina- 
tion, and  in  part  because  of  a  sulphurous  odor  which  often  characterizes 
the  water. 

Artesian  wells  have  come  into  extensive  use  within  the  past  thirty 

'  The  position  of  this  valley  was  noted  first  by  Mr.  Samuel  Artingstall  about  1886,  while  city 
engineer  of  Chicago. 


584  THE  ILLINOIS  GLACIAL  LOBE. 

years.  The  first  well  was  sunk  in  1864  in  the  northwest  part  of  the  city, 
on  the  hig-hest  ground  then  within  the  city  limits,  and  at  an  altitude  of  31  feet 
above  Lake  Michigan,  the  precise  location  being-  at  the  corner  of  Chicago 
and  Western  avenues.  This  well  was  sunk  by  a  band  of  Spiritualists  with 
a  -saew  to  ^prospecting  for  petroleum,  and  it  is  reported  that  the  site  of  the 
well  was  determined  by  Mr.  James,  a  so-called  medium,  while  entranced. 
Onl}-  a  small  amount  of  oil  was  found,  but  at  a  depth  of  711  feet  a  strong 
flow  of  water  was  struck,  which  rose  to  a  height  of  80  feet  above  the 
surface,  or  111  feet  above  Lake  Michigan.  A  second  well  only  a  few  feet 
distant  was  sunk  the  following  jem;  which  obtained  a  flow  of  water  at  a 
depth  of  694  feet.  The  history  of  these  wells  is  set  forth  in  an  interesting 
manner  in  a  pamphlet  entitled  "History  of  the  Chicago  artesian  well," 
by  George  A.  Shufeldt,  jr.,  issued  by  the  Religio-Philosophical  Publishing 
Association  of  Chicago  in  1867.  Mr.  W.  T.  B.  Read,  who  drilled  the  wells, 
still  resides  in  the  city.^  He  reports  that  the  head  has  decreased  to  such  an 
amount  that  the  water  now  stands  15  or  20  feet  below  the  surface,  or  nearlj^ 
100  feet  below  its  original  head,  and  that  the  wells  are  not  in  use.  These 
wells  apparently  obtained  their  supply  of  water  from  the  Galena  limestone, 
the  depth  being  insufficient  to  touch  the  St.  Peter  sandstone. 

Within  a  few  years  after  the  drilling  of  the  wells  just  noted,  several 
deeper  ones  were  sunk  in  the  city  and  strong  flows  were  obtained.  The 
earlier  ones  usually  reached  the  St.  Peter  sandstone,  but  it  is  probable  that 
much  of  then*  supply  came  from  hig-her  strata.  At  the  present  time  there 
are  several  hundred  wells  Avithin  the  city  used  by  the  various  industries 
which  demand  large  quantities  of  water.  A  large  part  of  them  penetrate 
only  to  the  St.  Peter  sandstone,  but  many  enter  the  underlying  limestone 
and  not  a  few  reach  the  Potsdam  sandstone.  The  deepest  ones  are  about 
2,700  feet.  At  this  depth  water  is  much  more  saline  than  in  the  St.  Peter 
sandstone  or  Galena  limestone.  The  disadvantage  resulting  from  salinity 
will  probably  restrict  the  boring  of  wells  in  the  future  to  depths  of  not  more 
than  2,500  feet.  The  boring  of  so  many  wells  within  a  limited  area  has 
led  to  such  an  excessive  drain  upon  the  rock  strata  that  the  head  is  ke^Jt 
below  the  normal,  and  an  ovei-flow  is  now  rarely  obtained. 

The  deepest  drift  encountered  in  Cook  County,  so  far  as  known  to  the 
writer,  is  in  a  well, at  Samuel  Church's,  near  the  center  of  the  northwest 

'  At  950  West  CliicMyd  iivoniie. 


WELLS  OF  COOK  COUiTTY,  ILLII^OIS.  585 

township  (sec.  22,  T.  42,  R.  9  E.).  This  boring  reached  a  depth  of  315  feet 
without  encountering  rock  or  obtaining  water.  As  the  altitude  there  is 
about  825  feet,  the  boring  reached  a  level  only  70  feet  below  that  of  Lake 
Michigan.  Another  boring  5  rods  distant  obtained  a  strong  well  from 
glacial  gravel  at  a  depth  of  170  feet.  Between  this  well  and  the  city  of 
Elgin  several  wells  are  found  to  enter  rock  at  depths  of  220  to  240  feet. 

Two  wells  east  of  Elgin  are  reported  to  have  passed  through  an  old 
soil  beneath  the  till.  In  one  well  the  soil  occurs  at  the  base  of  the  drift  at 
a  depth  of  67  to  70  feet.  In  the  other  it  occurs  at  about  165  feet,  while  the 
rock  is  entered  at  192  feet.  The  wells  in  that  vicinity  penetrate  a  bluish 
till,  but  on  the  borders  of  Fox  River  a  brown  or  reddish  till  is  reported  to 
extend  to  considerable  depth. 

A  well  one-half  mile  west  of  Spaulding  Station,  137  feet  in  depth, 
enters  rock  at  120  feet.     The  drift  is  mainly  blue  till. 

At  Bartlett  several  wells  reach  a  depth  of  90  or  100  feet,  mainly 
through  till.  At  Ontarioville  the  wells  of  greatest  strength  are  found  at 
depths  of  60  feet  or  more,  and  occasionally  reach  140  feet  without  entering 
rock. 

In  Palatine  Township  a  large  number  of  deep  wells  have  been  sunk, 

partly  because  of  the  difficulty  in  obtaining  water  at  shallow  depths  and 

partly  for  the  purpose  of  obtaining  an  overflow.    At  the  time  of  the  writer's 

visit  to  that  township,  in  1887,  there  were  not  less  than  25  flowing  wells. 

They  are  located  principally  in  the  central  portion,  near  the  village  of 

Palatine,  but  occasional  flows  are  obtained  in  other  parts  of  the  township  as 

well  as  in  neighboring  townships.     In  the  southwest  part  the  altitude  is  too 

great  for  a  flow,  but  several  wells  have  been  sunk  there  to  depths  of  150 

to  180  feet  without  reaching  rock.     The  following  wells  in  the  village  of 

Palatine  serve  to  show  the  differences  in  depth  of  the  wells  and  the  relation 

to  rock  strata: 

Flowing  wells  at  Palatine,  Illinois. 

Feet. 

Palatine  town  well,  enters  rock  at  152  feet 160 

Palatine  railroad  well,  crust  of  rock  at  bottom 165 

Palatine  deep  artesian  well,  enters  rock  at  147  feet 1,  656 

Palatine  Flax  Mill,  does  not  reach  rock , 170 

One  block  north  of  Flax  Mill,  not  to  rock 70 

Palatine  Cheese  Factory,  crust  of  rock  at  bottom 163 

The  well  at  the  cheese  factor}^,  when  first  made,  would  rise  into  the 
second  story,  and  that  at  the  flax  mill  to  a  level  10  feet  above  the  surface. 


586  THE  ILLINOIS  GLACIAL  LOBE. 

The  other  wells  show  a  rise  scarcely  so  high,  though  their  mouths  are  at 
an  equally  low  elevation.  The  well  70  feet  in  depth  has  a  strong  flow  of 
chalybeate  water.  The  strongest  flow  is  from  the  cheese  factory  well — 60 
gallons  per  minute.  The  crust  of  rock  reported  in  these  wells  is  perhaps  a 
ferruginous  incrustation  of  gravelly  drift,  such  as  is  often  formed  above 
water  beds  in  the  (h'ift.  In  the  deep  artesian  -well  a  strong  flow  of  water  is 
reported  from  a  depth  of  800  feet  as  well  as  from  near  the  base  of  the  drift. 
The  collecting  area  for  the  shallow  wells  is  thought  to  be  in  the  portion  of 
the  Valparaiso  moraine  west  and  north  of  Palatine,  which  attains  an  altitude 
of  100  to  120  feet  above  the  station.  The  superficial  draiuag-e  is  very  jjoor 
along  this  moraine,  and  much  of  the  water  must  evaporate  or  find  outlet 
by  underground  passages.  The  collecting  area  seems  adequate  for  supply- 
ing the  flowing  well  distinct.  The  following  section  of  a  well  at  the  flax 
mill  will  illusti-ate  the  character  of  the  deposits  penetrated  in  each  of  the 

wells : 

Section  of  well  at  Flax  Mill,  in  Palatine,  Illinois. 

Feet. 

Yellow  till - 10-12 

Blue  till - 25-30 

Water-bearing  gravel 3-4 

Blue  till,  with  occasional  thin  beds  of  sand  and  gravel,  yielding  water 125 

The  lower  portion  of  the  till  is  said  to  be  more  sandy  than  the  upper. 
In  the  north  part  of  Palatine  Township  there  are  several  wells  ranging  in 
depth  from  80  to  165  feet,  which  show  strong  hydi'ostatic  pressure.  On  the 
lowest  ground  they  occasionally  rise  within  5  or  10  feet  of  the  top,  and  in 
two  or  more  instances  they  ovei-flow. 

In  the  township  adjoining  Palatine  on  the  south  (T.  41,  R.  10  E.) 
flowing  wells  have  been  obtained  along  a  tributary  of  Salt  Creek  in  sections 
23,  25,  and  26,  at  depths  of  27  to  45  feet.  Being  so  shallow  they  differ  Init 
little  from  springs  which  occur  in  that  ^'^cinity.  A  few  deep  wells  have 
been  made  in  the  western  part  of  this  township.  The  following-  section  is 
from  one  in  its  northwest  corner,  at  an  altitude  about  825  feet: 

Section  of  a  icell  in  northwest  jyart  of  T.  41,  R.  10  E. 

Feet. 

Yellow  till 10-15 

Blue  till 125 

Black  soil 4 

Sandy  till 50 

Gravel  with  water 2 

Total  depth 195 


WELLS  OF  COOK  COUNTY,  ILLINOIS.  587 

At  Arlington  Heights  a  well  drilled  to  a  depth  of  800  feet  penetrates 
128  feet  of  drift.  No  further  data  concerning  the  well  were  obtained.  A 
well  in  this  village  penetrated  a  black  soil  beneath  blue  till  at  a  depth  of  70 
to  75  feet,  beneath  which  it  entered  another  sheet  of  till.  A  well  2^  miles 
north  of  Arlington  Heights  entered  rock  at  a  depth  of  195  feet. 

At  Des  Plaines  Village,  which  is  situated  on  a  gravelly  plain,  wells 
penetrate  about  12  feet  of  gravel  before  entering  till.  Some  obtain  their 
supply  in  this  gravel,  others  from  gravel  associated"  with  the  till.  The 
depth  seldom  exceeds  30  feet.  The  public  sup^jly  is  from  an  8-inch  well 
200  feet  in  depth.^ 

A  well  on  the  farm  of  John  Back,  near  Schermerville,  162  feet  in 
depth,  enters  rock  at  147  feet.  In  the  Adllage  of  Schermerville  wells  are 
often  60  feet,  and  in  some  instances  over  100  feet  in  depth,  and  obtain  water 
from  gravel  beneath  the  till. 

At  the  village  of  Oak  Gt-len  several  flowing  wells  have  obtained  water 
either  near  the  base  of  the  drift  or  in  the  upper  part  of  the  underlying 
limestone  at  depths  of  90  to  120  feet.  Mr.  F.  N.  Hoffman's  well,  118  feet  in 
depth,  struck  one  water  vein  in  gravel  at  78  to  80  feet  and  another  at  the 
top  of  the  limestone  at  114  to  118  feet.  Water  in  this  well  rises  4  feet 
above  the  surface.  A  well  near  Oak  Glen,  in  sec.  25,  160  feet  in  depth, 
does  not  reach  rock,  though  its  mouth  is  scarcely  60  feet  above  Lake 
Michigan. 

At  Park  Ridge,  at  an  altitude  660  feet  above  tide,  an  artesian  well 
enters  rock  at  103  feet.  The  drift  is  mainly  till.  No  further  data  Avere 
obtained.  A  well  about  3  miles  north  of  Park  Ridge  at  slightly  higher 
altitude  enters  rock  at  110  feet. 

At  Winnetka,  at  the  residence  of  Mr.  Lloyd,  a  well  1,570  feet  in  depth 
enters  rock  at  150  feet.  The  water  rises  to  a  level  nearly  40  feet  above 
Lake  Michigan.  Wells  are  obtained  in  this  callage  at  depths  of  20  to  50 
feet  in  beds  of  gravel  associated  with  the  till. 

At  Wilmetterock  is  entered  at  about  140  feet,  or  nearly  100  feet  below 
the  level  of  Lake  Michigan.  A  deep  well  has  a  head  about  20  feet  above 
the  lake  level.     No  further  data  were  obtained. 

An  artesian  well  at  Evanston,  1,602  feet  in  depth,  enters  rock  at  72 
feet,  or  about  42  feet  below  the  level  of  Lake  Michigan.      Water  rises  to  a 


'  Manual  of  American  Waterworks,  1897. 


588  THE  ILLINOIS  GLACIAL  LOBE. 

height  34  feet  above  lake  level,  or  Gl-t  feet  above  tide.  The  well  reaches 
the  Potsdam  sandstone.  An  analysis  of  the  water  is  presented  in  the 
Seventeenth  Annual  Report  of  this  Survey.-^  The  temperature  of  the  water 
is  61.7  degrees  Fahr.  ]\Iany  wells  are  obtained  in  this  city  at  a  depth  of 
35  feet  or  less  near  the  bottom  of  the  beach  sand.  The  peaty  deposits 
which  occur  at  that  horizon  in  some  cases  g'ive  the  water  an  unpleasant 
odor.  The  use  of  private  wells  is  decreasing,  being  supplanted  by  the 
public  supplj"  which  is  pumped  from  Lake  Michigan. 

In  the  vicinity  of  Niles  Center  several  wells  strike  rock  at  depths 
ranging  from  85  to  over  100  feet.  T^e  gravel  and  sand  of  the  lake  beach 
is  8  to  12  feet  in  depth.     The  underlying  glacial  di'ift  is  mainly  till. 

At  Morton  a  well  115  feet  in  depth  enters  rock  at  about  100  feet.  The 
di'ift  is  mainly  blue  till. 

In  Bowman-sdlle  and  vicinity  several  wells  near  the  Chicago  River 
reach  a  depth  of  80  feet  Avithout  striking-  rock.  In  some  instances  they 
penetrate  about  20  feet  of  beach  gravel.  A  well  at  Rose  Hill  Cemetery, 
near  Bowman ville,  strikes  rock  at  100  feet.  The  upper  30  feet  is  gravel 
and  sand,  beneath  which  is  a  compact  till  extending  to  the  rock. 

In  sevei'al  suburbs  in  the  northwest  part  of  Chicag'O  rock  is  struck  in 
artesian  wells  at  60  to  100  feet,  as  follows: 

Drift  in  artesian  wells  in  northtcest  part  of  Chicago. 

Feet. 

Jeflerson  Park 68 

Irving  Park 79 

Montrose 60 

Norwood  Park 90 

Near  County  Infirmary 71 

Same  locality 101 

Oak  Park 65,  85,  and  45 

Near  Cragin 20 

111  all  of  these  wells  the  greater  part  of  the  drift  is  blue  till.  The 
beach  gravel  and  sand  seldom  amount  to  more  than  5  or  10  feet. 

A  well  at  River  Park,  near  the  Des  Plaines  RiA^er,  115  feet  in  depth, 
enters  rock  at  100  feet.  A  well  at  Turner  Park  obtains  Avater  from  sand 
below  till  and  just  above  the  rock  at  a  depth  of  80  feet.  Mr.  Koch,  near 
Dunning,  has  a  Avell  114  feet  in  depth  which  did  not  reach  rock.  "Wells  in 
the  vicinity  of  Galewood,  60  feet  in  depth,  are  mainly  through  till  and  do 
not  reach  rock.     Wells  at  MayAA'Ood,  40  feet  in  depth,  do  not  reach  rock, 

'Part  II,  p.  827. 


WELLS  OF  COOK  COUNTY,  ILLINOIS.  589 

but  within  2  miles  west  of  Maywood  rock  is  struck  at  about  30  feet.  The 
Manual  of  American  Waterworks  (1897)  reports  that  the  public  supply  is 
from  an  artesian  well.  A  well  in  the  Des  Plaines  valley  near  the  Twelfth 
street  bridge  does  not  reach  rock. 

At  Riverside  the  water  supply  is  obtained  from  artesian  wells  about 
2,200  feet  in  depth,  which  reach  the  Potsdam  sandstone.  The  supply  is 
partly  from  the  St.  Peter  and  other  strata  above  the  Potsdam.  The  wells 
originally  overflowed,  but  the  head  is  now  20  feet  below  the  surface,  or 
about  600  feet  above  tide.  With  a  diameter  of  but  3J  inches,  the  capacity 
of  one  of  these  wells  is  estimated  to  be  more  than  one  million  gallons  per 
day. 

At  Lagrange  the  public  supply  is  from  artesian  wells,  but  no  data  were 
obtained  concerning  their  depths  and  capacities.  In  the  east  part  of  the 
village  a  flowing  well  is  obtained  from  the  drift  at  a  depth  of  21  feet.  Rock 
outcrops  within  the  limit  of  this  village  at  a  higher  elevation  than  the  mouth 
of  this  well.  On  the  plain  east  of  Lagrange  rock  is  frequently  struck  at 
about  20  feet.  The  drift  there  is  mainly  a  blue  clay,  there  being  only  5  or 
6  feet  of  yellow  clay  at  surface.  In  some  cases  sand  and  gravel  occur  just 
above  the  rock.  West  of  Lagrange,  in  the  vicinity  of  Western  Springs, 
wells  often  reach  a  depth  of  40  or  50  feet  without  entering  rock. 

Borings  in  the  vicinity  of  Summit  show  the  depth  to  rock  to  range  from 
10  feet  or  less  to  fully  40  feet.  The  beach  gravel  in  the  south  part  of  the 
village  is  shown  by  a  gravel  pit  to  have  a  depth  of  20  feet.  Beneath  this 
gravel  is  blue  till.  On  the  plain  southeast  from  Summit  several  wells  are 
sunk  45  to  55  feet  without  reaching  rock. 

At  Washington  Heights  a  well  at  Klein's  Hotel  enters  rock  at  70  feet, 
penetrating  the  following  beds: 

Section  of  icell  at  a  hotel  in  Washington  Heights. 

Feet. 

Gravel 3 

Yellow  till 5 

Blue  till 63 

Limestone 3 

Other  wells  are  obtained  in  that  vicinity  at  shallower  depths.  The 
public  water  supply  is  from  a  deep  well.^ 

A  well  at  Morgan  Park,  on  the  crest  of  the  Blue  Island  till  ridge,  1,046 
feet  in  depth,  has  a  head  594  feet  above  tide.     Limestone  is  entered  at  a 

'  Manual  of  American  Waterworks. 


590  THE  ILLINOIS  GLACIAL  LOBE. 

depth  of  163  feet,  or  about  100  feet  below  the  level  of  Lake  Michigan. 
The  well  record  indicates  a  soft  till  extending-  fi'om  the  surface  to  a  depth 
of  86  feet,  beneath  which  there  is  a  harder  material  called  shale,  but  perhaps 
a  till,  77  feet  in  depth.  Another  well  in  Morgan  Park  is  reported  to  have 
struck  limestone  at  a  depth  of  only  90  feet. 

At  Riverdale  rock  is  entered  at  about  45  feet,  at  Dolton  at  35  or  40 
feet,  and  in  the  vicinity  of  Harvey  at  20  or  25  feet.  The  public  water 
supply  at  Harvey  is  obtained  from  deep  wells,  one  of  which  derives  its 
water  from  the  St.  Peter  at  1,300  feet  and  another  terminates  in  Potsdam  at 
2,075  feet. 

At  Blue  Island  wells  usually  reach  water  in  sand,  connected  with  the 
lake  occupancy,  at  a  depth  of  about  25  feet. 

On  "Lanes  Island,"  in  the  Sag  outlet,  several  wells  reach  a  depth  of 
30  feet  without  entering  rock.  After  penetrating  4  to  8  feet  of  sand  they 
are  mainly  through  till. 

At  the  village  of  Worth  wells  usually  obtain  water  at  about  16  feet 
in  sand  below  till.  Rock  is  exposed  along  the' Sag  outlet  in  that  vicinity  at 
abotit  the  level  of  Lake  Michigan.  A  well  4  miles  east  of  Worth,  in  sec. 
23,  T.  27,  R.  13  E.,  reaches  rock  at  55  feet.     The  drift  is  mainly  till. 

On  the  island-like  tract  of  moraine  between  the  Sag  outlet  and  Des 
Plaines,  northwest  of  Worth,  several  wells  reach  a  depth  of  about  80  feet 
without  entering  rock.     They  are  mainly  through  blue  till. 

On  the  Valparaiso  moraine,  in  the  south  part  of  Cook  County  near 
Alpine,  several  wells  have  a  depth  of  80  feet  without  entering  rock.  Small 
amounts  of  inflammable  gas  have  been  found  in  some  of  these  wells. 

In  the  vicinity  of  Matteson  and  northward  in  T.  35,  R.  13  E.,  wells 
frequently  reach  depths  of  50  to  65  feet  without  entering-  rock.  In  the 
vicinity  of  New  Bremen,  in  T.  36,  R.  13  E.,  the  wells  are  frequently  75 
feet  in  depth  and  obtain  water  in  gravel  beneath  the  till. 

In  the  vicinity  of  Gleuwood  wells  along  the  beach  penetrate  8  to  12 
feet  of  gravel  before  entering  till,  and  strike  rock  at  about  30  or  35  feet. 

A  flowing  well  was  obtained  by  Mr.  Winterhofli'e  on  his  farm  in  sec.  6, 
T.  35,  R.  15  E.,  at  a  depth  of  75  feet  without  reaching  rock.  It  was  through 
till  the  entire  depth.  A  neighboring  well  at  Lewis  Peter's  enters  rock  at  85 
feet,  but  the  water  level  is  14  feet  below  the  surface.  Another  well,  in  sec. 
12,  T.  35,  R.  14  E.,  strikes  rock  at  85  feet  and  there  obtains  water,  which 


WELLS  OF  DUPAGE  COUNTY,  ILLINOIS.  591 

rises  within  2  feet  of  the  surface.  Still  another  well,  in  sec.  7,  T.  35,  R.  15 
E.,  only  60  feet  in  depth,  encountered  rock  at  the  bottom,  which  may  possibly 
have  been  a  bowlder. 

The  public  water  supply  for  Chicago  Heights  is  obtained  from  four 
wells  about  200  feet  in  depth  located  on  the  plain  north  of  the  village.  The 
head  is  not  sufficient  to  cause  an  overflow.  The  drift  in  the  vicinity  of  this 
village  is  but  20  or  30  feet  in  depth  and  some  of  the  private  wells  enter  the 
rock;  occasionally  they  are  sunk  to  a  depth  of  80  or  90  feet.  In  the  dis- 
trict east  of  Chicago  Heights,  as  far  as  the  State  line,  wells  are  usually 
obtained  at  a  depth  of  about  35  feet,  from  g-ravel  below  till. 

DUPAGE  COUNTY. 
GENERAL    STATEMENT. 

Dupage  County  is  situated  west  of  the  middle  portion  of  Cook 
County,  and  has  an  area  of  but  340  square  miles.  Wheaton,  the  county 
seat,  is  situated  near  its  g-eographic  center.  Its  di-ainage  is  southward,  the 
eastern  border  being  tributary  to  Salt  Creek  and  the  middle  and  western 
portions  to  the  East  and  West  Dupage  rivers,  respectively.  Like  the 
portion  of  Cook  County  on  the  north,  it  is  poorly  drained,  although  stand- 
ing much  above  the  bordering  plain  on  the  east.  The  eastern  two-thirds  of 
the  county  is  occupied  by  the  Valparaiso  moraine,  which  carries  numerous 
sloughs  and  basins  among  its  knoHs  and  ridges.  It  affords  excellent  pas- 
ture lands  and  is  extensively  used  in  dairying,  the  leading  pursuit  of  the 
county. 

On  the  dairy  farms  wells  are  frequently  sunk  to  depths  of  100  feet  or 
more.  The  thickest  drift  section  obtained  is  162  feet,  and  20  wells  which 
reach  rock  show  an  average  depth  of  86  feet,  while  17  of  the  deep  wells 
which  fail  to  reach  rock  show  an  average  depth  of  94  feet.  From  these 
sections,  which  are  distributed  widely  over  the  county,  the  thickness  of  the 
drift  may  be  inferred  to  average  not  less  than  100  feet.  The  drift  is  thin- 
nest in  the  southwestern  portion,  on  the  borders  of  the  West  Dupage 
Kiver,  where  numerous  quarries  of  limestone  have  been  opened.  Rock  also 
comes  to  the  surface  near  Elmhurst,  in  the  southeast  part.  The  drift  in  this 
county,  as  in  northwestern  Cook  County,  consists  mainly  of  a  blue  till,  but 
beds  of  sand  and  gravel  are  associated  with  the  till  at  various  levels  and 
supply  the  water  for  wells. 


592  THE  ILLINOIS  GLACIAL  LOBE. 


INDIVIDUAL    AVELLS. 


Ill  the  northwestern  township  of  the  county,  sections  of  thi-ee  deep 
wells  were  obtained  near  Wayne,  one  of  which  in  sec.  7,  105  feet,  and  one 
in  sec.  8,  150  feet,  in  depth,  do  not  reach  rock,  but  one  in  sec.  33  enters 
rock  at  162  feet.  In  the  first  two  wells  a  large  amount  of  sandy  material 
was  penetrated,  but  the  third  well  penetrated  nothing  but  till. 

In  the  middle  township  of  the  north  tier  several  wells  have  been  sunk 
near  Roselle  to  a  depth  of  100  feet  or  more  without  entering  rock.  The 
majority  of  them  are  mainly  through  till. 

In  the  northeast  township  several  flowing  wells  have  been  obtained  in 
the  vicinity  of  Itasca  at  shallow  depths  along  a  tributary  of  Salt  Creek. 
The  depths  are  but  20  to  30  feet,  and  the  water  rises  scarcely  5  feet  above 
the  surface.  There  are  also  numerous  shallow  flowing  wells  along  Salt 
Creek  between  Salt  Creek  Station  and  Elmhurst.  It  should  be  noted  that 
this  flowing-well  district  is  adjacent  to  that  of  Cook  County,  discussed 
above.  The  altitude  is  75  feet  or  more  lower  than  at  Palatine,  being 
scarcely  more  than  650  feet  along  Salt  Creek  Valley,  and  about  690  feet 
at  Itasca.  Neighboring  portions  of  the  Valparaiso  morainic  system  on  the 
west  rise  fully  100  feet  above  the  wells  at  Itasca,  and  it  is  probable  that 
this  moraine  constitutes  the  absorbing  area. 

A  well  at  Benson ville,  about  2,000  feet  in  depth,  penetrates  97  feet  of 
di-ift.     No  further  data  concerning  the  well  were  obtained. 

At  Elmhurst  records  were  obtained  of  two  wells  which  strike  rock  at 
70  and  98  feet  respectively.  Within  a  mile  west  of  these  wells  a  limestone 
quarry  is  opened  at  a  level  only  15  or  -20  feet  Delow  the  well  mouths. 
About  3  miles  south  also  a  quany  is  opened  on  the  blutf  of  Salt  Creek. 
The  public  water  supply  is  pumped  from  a  spring  about  3  miles  distant 
from  the  town.^ 

Along  the  valley  of  Salt  Creek,  south  from  Elmhurst,  wells  are  in 
jjlaces  sunk  to  a  depth  of  50  feet,  mainly  through  gravel.  At  the  village 
of  FuUersburg,  however,  wells  obtain  their  supply  of  water  in  gravel  at  a 
depth  of  but  12  feet. 

At  Hinsdale  the  public  water  supply  is  obtained  from  a  well  864  feet 
in  depth..  This  is  reported  by  the  Manual  of  Ameiican  Waterworks  to 
aff'ord  1,000,000  gallons  per  day.     The  last  edition  of  this  manual  reports  a 

'  Manual  of  American  Waterworks,  1897. 


WELLS  OF  DUPAGE  COUNTY,  ILLINOIS.  593 

second  deep  well  in  use.  The  drift  in  the  vicinity  of  Hinsdale  is  about 
100  feet  in  depth  and  is  mainly  till.  On  the  moraine  west  and  northwest 
from  this  village  several  wells  show  the  drift  to  be  over  150  feet  in  thick- 
ness. One  at  a  brickyax-d,  in  sec.  10,  T.  38,  K.  11,  190  feet  in  depth, 
enters  rock  at  159  feet;  another  near  Clarendon  Hills,  160  feet  in  dejath, 
does  not  enter  rock.  In  each  of  these  wells  and  in  all  the  wells  in  that 
vicinity  the  drift  is  mainly  a  blue  till.  In  the  well  near  Clarendon  Hills  a 
very  hard  till  was  entered  at  a  depth  of  130  feet,  which  is  perhaps  an  older 
deposit  than  the  soft  till  above  it. 

In  the  vicinity  of  Downers  Grove  several  wells  have  been  sunk  to  a 
depth  of  over  100  feet  without  entering  rock.  One  well  enters  rock  at  a 
depth  of  130  feet.  In  these  wells  sand  is  usually  found  below  the  blue  till 
at  depths  of  100  to  120  feet.  The  Manual  of  American  Waterworks  (1897) 
reports  that  the  public  water  supply  is  from  two  10-inch  deep  wells. 

Near  Lisle  the  drift  is  of  gravelly  constitution,  and  wells  are  usually 
obtained  at  about  50  feet.  A  well  south  of  the  village,  in  section  12,  is  157 
feet  in  depth  and  entered  rock  at  aboiit  100  feet.  This  well  was  mainly 
through  till. 

At  Wheaton  the  public  water  supply  is  from  a  well  178  feet  in  depth 
and  10  inches  in  diameter,  which  is  estimated  to  yield  300  gallons  per 
minute.  The  limestone  was  entered  at  a  depth  of  116  feet.  About  2  miles 
northeast  of  Wheaton,  at  an  equally  high  elevation  (750  feet),  rock  was 
entered  at  a  depth  of  only  70  feet. 

Several  wells  have  been  sunk  in  the  vicinity  of  Prospect  Park  and 
Lombard,  which  obtained  water  from  gravel  at  about  50  feet.  The  di-ift  in 
that  vicinity  is  gravelly. 

In  the  vicinity  of  Turner  Junction  wells  are  occasionally  sunk  to  a 
depth  of  about  100  feet  without  encountering  rock.  A  well  3  miles  south- 
west of  the  village  entered  rock  at  a  depth  of  116  feet.  A  deep  well  has 
been  sunk  by  the  Chicago  and  Northwestern  Eailway  Company  at  Turner 
Junction,  but  no  data  concerning  it  have  been  obtained. 

At  Naperville  wells  usually  reach  water  in  gravel  at  a  depth  of  about 
30  feet.  The  drift  east  and  south  from  this  village  is  gravelly.  It  ranges 
in  thickness  from  a  few  feet  up  to  100  feet  or  more.  In  several  places  near 
Naperville  limestone  quarries  have  been  opened.  West  from  Naperville  in 
the  vicinity  of  Eola  the  drift  is  about  100  feet  in  depth,  mainly  till. 

MON  XXXVIII 38 


594  THE  ILLINOIS  GLACIAL  LOBE. 


KANE  COUNTY. 
GENERAL   STATEMENT. 


Kane  County  is  situated  west  of  Cook  and  Dupage,  and  lias  an  area  of 
540  square  miles.  It  includes  the  tlll•i^^ng•  cities  of  Elgin  and  Aurora,  and 
its  countv  seat  is  Geneva.  Fox  River  flows  in  a  southerly  course  tlu-ough 
the  eastern  part  of  the  county  and  is  the  line  of  discharge  for  most  of  the 
drainage.  The  greater  part  of  the  count}''  has  such  imperfect  drainage  that 
large  areas  have  been  artificially  drained.  It  is  in  the  center  of  the  great 
dairy  district  of  northeastern  Illinois,  and  the  greater  part  of  the  county  is 
devoted  to  dair^^ng^  Numerous  deep  wells  have  been  sunk  on  the  farms, 
some  of  them  reaching  depths  of  over  200  feet  before  encountering  rock, 
but  in  the  southeastern  part  of  the  county  rock  is  exposed  extensively 
in  the  bluffs  of  Fox  River  and  is  struck  at  comparatively  shallow  depths 
in  the  wells.  The  portion  of  the  county  north  from  the  latitude  of  Geneva 
is,  as  previously  described,  largely  occupied  by  a  complicated  system  of 
morainic  belts,  but  the  southern  portion  of  the  county  has  generally  a 
nearly  plane  surface.  These  moraines  were  formed  at  the  Wisconsin  stage 
of  glaciation  and,  like  the  Valparaiso  morainic  sj^stem  to  the  east,  consist 
largely  of  a  soft  blue  till.  In  several  of  the  deep  wells  a  black  soil  has  been 
found  beneath  the  blue  till,  and  under  this  soil  a  hard  till  is  penetrated. 
This  liard  till  is  apparenth'  of  much  earlier  age  than  the  di-ift  of  the  Wis- 


consui  stage. 


INDIVIDUAL    WELLS. 


In  the  northwest  township  records  were  obtained  of  several  wells  near 
the  village  of  Hampshire  Avhich  reach  a  deptli  of  over  100  feet  without 
entering  rock.  A  well  at  the  brick  yards  in  Hampshire  is  102  feet,  and  one 
at  the  Warner  Lock  Company  factory  is  118  feet,  each  being  mainly 
tlu-ough  blue  till.  ( )u  a  farm  near  Hampshire  one  well  reached  a  depth  of 
180  feet.  On  the  crest  of  a  moraine  east  of  Hampshire,  near  Briar  Hill 
Station,  at  an  elevation  975  feet  above  tide,  a  Avell  175  feet  in  depth  is 
entirely  tlu-ough  till  except  one  foot  of  sand  at  the  bottom.  On  this  same 
moraine  records  of  several  wells  were  obtained  which  find  water  in  abiui- 
dance  at  a  depth  of  20  to  35  feet,  and  the  great  majority  of  wells  in  the 
township  are  less  than  40  feet  in  deptli. 


WELLS  OF  KANE  COUNTY,  ILLINOIS.  595 

In  the  middle  township  of  the  north  tier  the  following-  records  of  deep 
wells  were  obtained: 

Deep  drift  wells  in  northern  Kane  County. 

Feet- 
Mr.  Kelly,  sec.  32 130 

Mr.  Roch,  sec.  20 , 161 

Mr.  Huuter,  sec.  21 106 

Near  Gilbert  Station,  in  sec.  14 293 

In  the  last  of  these  wells  an  old  soil  was  penetrated  at  the  base  of  the 
blue  till,  at  a  depth  of  180  to  183  feet,  beneath  which  was  a  hard  till 
extending  to  the  rock,  which  was  entered  at  217  feet. 

At  Dundee,  in  the  northeast  township  of  the  county,  wells  on  the  gravel 
terrace  along  Fox  River  are  about  60  feet  in  depth-  The  public  water  supply 
is  obtained  from  springs,  but  in  the  part  of  the  village  east  of  Fox  River 
private  wells  are  still  in  use.  Mr.  Francis  Perry  obtained  a  flowing  well  in 
Fox  River  Valley  north  of  Dundee,  near  the  top  of  the  limestone,  at  a  depth 
of  181  feet.  An  old  soil  was  struck  at  about  155  feet.  Water  will  flow 
from  a  pipe  16  feet  above  the  surface.  This  well  is  but  a  short  distance 
from  the  flowing  wells  in  McHemy  County,  near  Algonquin,  reported  above. 

The  city  of  Elgin  obtains  its  public  supply  by  pumping  from  Fox 
River.  There  are,  however,  many  private  wells  within  the  city,  and  a  few 
deep  artesian  wells.  The  wells  usually  obtain  water  without  entering  rock 
at  depths  of  50  feet  or  less.  The  thickness  of  the  drift  in  a  well  at  the 
Elgin  Shoe  Factory  is  123  feet,  and  an  old  soil  was  struck  at  108  to  113  feet. 
The  drift  above  the  soil  is  mainly  gravel  and  cobble,  but  below  it  is  a  red- 
dish till.  Usually  rock  is  struck  at  a  depth  of  less  than  100  feet.  The 
following'  data  concerning-  artesian  wells  were  furnished  by  W.  S.  Gamble, 
city  engineer.  A  well  at  the  Elgin  Watch  Factory,  at  an  elevation  715 
feet  above  tide,  has  a  depth  of  2,026  feet  and  a  diameter  of  6  inches.  It 
obtains  sulphurous  water  from  St.  Peter  sandstone  at  650  to  700  feet,  and 
soft  water  from  Potsdam  at  2,024  feet.  A  well  at  the  Plospital  for  the 
Insane,  at  an  altitude  735  feet  above  tide,  has  a  depth  of  2,230  feet.  This 
also  obtains  water  both  from  the  St.  Peter  and  the  Potsdam  sandstone. 
The  Elgin  Creamery  Company  have  a  well  1,400  feet  in  depth,  which 
obtains  water  from  the  Galena  limestone  at  487  to  514  feet,  and  from  sand- 
stone at  650  to  700,  972,  1,208,  and  1,398  feet.  The  upper  veins  are  more 
sulphurous  than  the  lower.     The  Illinois  Condensing  Company  have  a  well 


596  THE  ILLINOIS  (JLAOIAL  LOBE. 

1,876  feet  in  depth,  which  aijparently  obtains  the  greater  part  of  its  water 
from  the  St.  Peter  sandstone  at  650  to  700  feet.  The  heads  at  the  several 
wells  vary  from  716  to  742  feet  above  tide,  the  lowest  head  being  at  the 
creamery  and  the  higliest  at  the  watch  factory  well.  An  analysis  of  the 
water  from  the  well  at  the  Hospital  for  the  Insane  is  published  in  the 
Seventeenth  Annual  Report  of  this  Survey.^ 

A  well  on  the  farm  of  Judge  Wilcox,  northwest  of  Elgin,  in  sec.  4, 
T.  41,  R.  8  E.,  127  feet  in  depth,  passed  through  an  old  soil  at  111  to  114 
feet  and  obtained  water  without  entering  rock.  The  altitude  at  the  well  is 
about  125  feet  above  Fox  River  Valley  at  Elgin,  or  850  feet  above  tide. 

Sections  of  thi-ee  deep  wells  were  obtained  in  the  township  west  of 

Elgin,  as  follows : 

Deep  drift  wells  west  of  Elgin,  Illinois. 

Feet. 

Mr.Eussell,  sec.  12,  altitude  825  feet 100 

T.  Read,  see.  32,  altitude  925  feet 219 

Well  in  sec.  35;  altitude  900  feet 146 

None  of  the  wells  enter  rock,  and  in  each  well  the  drift  is  mainly  a 
blue  till.     In  the  last  one  an  old  soil  w^as  passed  through  at  131  to  137  feet. 

In  the  next  township  to  the  west,  T.  41,  R.  6  E.,  several  flowing  wells 
have  been  obtained  on  a  plain  between  morainic  ridges  at  an  altitude  about 
865  to  880  feet,  and  at  depths  ranging  from  56  to  86  feet,  as  follows: 

Floioing  icellsfrotn  drift  in  western  Kane  Comity. 

Feet. 
Sec.  3,  altitude  875  feet 75 

C.  B.  Godfrey,  sec.  15,  altitude  880  feet 72 

G.H.Brown,  sec.  22,  altitude  875  feet 64 

D.  AV.  Pierce,  sec.  27,  altitude  875  feet 70 

E.  E.  Barry,  see.  27,  altitude  865  feet 56 

S.  R.  Ellithorp,  sec.  27,  altitude  875  feet 86 

A  well  at  John  McDonough's,  in  sec.  26  of  this  townshij),  125  feet 
in  depth,  strikes  an  old  soil  at  40  feet.  This  soil  is  probably  referable  to 
the  Peorian  or  post-Iowan  interglacial  stage.  The  altitude  is  not  greatly 
different  from  that  of  the  flowing  wells,  yet  a  flow  was  not  obtained. 

A  well  at  the  mill  in  the  village  of  Burhngton,  165  feet  in  depth,  is 
in  rock  a  few  feet.  A  well  at  a  hotel  in  the  village  reaches  a  deptli  of 
100  feet  and  obtains  water  in  gravel  below  blue  till.  In  the  vicinity  of 
Burlington  several  wells  exceed  100  feet  in  depth.  One  in  sec.  5  is  114 
feet  and  another  99  feet.     One  in  sec.  17  is  117  feet  in  depth. 

'  Part  II,  p.  827. 


WELLS  OF  KANE  COUNTY,  ILLINOIS.  597 

In  the  vicinity  of  Richardson  several  wells  have  been  sunk  to  depths 
of  80  to  120  feet,  mainly  throug-h  till,  and  obtain  water  in  sand  and  gravel 
without  entering-  rock.  Mr.  Richardson  has  two  wells,  one  84  feet,  the  other 
87  feet;  Mr.  Dayton,  one  well,  117  feet;  Mr.  Frank  Paul  a  well  120  feet. 
Other  deep  wells  in  that  township  range  from  50  to  100  feet  or  more,  with 
an  average  about  75  feet.  Such  wells  are  much  stronger  than  those  obtained 
at  shallow  depths. 

In  T.  40,  R.  7  E.,  there  is  an  elevated  morainic  belt  in  which  the  drift 
probably  averages  over  200  feet.  Each  of  the  wells  which  enter  rock  pene- 
trate more  than  200  feet  of  di'ift,  and  one  well  reaches  a  depth  of  336  feet 
without  striking-  rock.  In  several  wells  an  old  soil  is  found  at  the  depth  of 
about  200  feet,  which  in  some  instances  is  probably  between  the  lowan  and 
Illinoian  drift  or  the  Sangamon  interglacial  stag'e.  The  following  wells  serve 
to  illustrate  the  above  statement.  At  J.  Powell's,  in  sec.  7,  altitude  about 
950  feet,  buried  soil  is  struck  at  195  to  200  feet  and  rock  is  entered  at  250 
feet.  The  well  is  continued  about  200  feet  into  the  rock.  At  M.  W.  Powell's, 
in  sec.  8,  on_ nearly  as  elevated  a  point  as  the  preceding,  a  well  about  500 
feet  in  depth  penetrates  234  feet  of  drift.  At  a  cheese  factory  in  section  19, 
at  an  elevation  of  950  feet,  is  a  well  336  feet  in  depth  which  did  not  reach 
rock.  An  old  soil  is  found  below  the  blue  till  at  198  to  200  feet,  with  a 
greenish  subsoil  beneath  it.  A  hard  till  of  light  gray  color  sets  in  at  240 
feet  and  extends  to  the  bottom  of  the  well.  Mr.  Beith,  in  sec.  28,  has  a 
well  228  feet  in  depth,  which  is  thought  to  strike  rock  at  the  bottom.  The 
altitude  is  probably  925  feet.  Mr.  L.  R.  Read,  in  sec.  32,  has  a  well  226 
feet  in  depth,  which  passed  through  an  old  soil  at  about  180  feet  and  entered 
rock  at  214  feet.     The  altitude  of  the  well  is  about  925  feet. 

In  the  \dcinity  of  St.  Charles  in  T.  40,  R.  8  E.,  several  wells  have  been 
sunk  to  a  depth  of  75  feet  or  more.  One  in  sec.  1  strikes  a  black  soil  below 
blue  till  at  a  depth  of  72  to  74  feet,  and  one  on  Mr.  Dunham's  farm,  in  the 
east  part  of  the  township,  passes  through  a  buried  soil  at  75  to  78  feet. 
The  altitude  at  these  wells  is  about  750  feet,  or  nearly  200  feet  below  that 
of  the  deep  wells  in  the  township  on  the  west  just  noted. 

At  Greneva  a  well  at  the  court-house  was  sunk  to  a  depth  of  2,500  feet, 
and  the  Glucose  Company  have  a  well  2,000  feet  in  depth ;  this  company 
also  has  a  well  400  feet  in  depth.  No  further  data  concerning  these  wells 
have  been  obtained.     The  village   stands   on  a  gravelly  plain  at  a  level 


598  THE  ILLINOIS  GLACIAL  LOBE. 

about  40  feet  above  Fox  River.  Wells  are  usually  obtained  without  sink- 
ing- below  tlie  river  level.  In  the  A-icinity  of  this  -^-illage  rock  is  often 
encountered  at  depths  of  but  15  or  20  feet.  The  di-ift  contiiuies  thin  south- 
ward past  Batavia,  and  many  wells  in  that  ^^llag■e  enter  the  rock.  Upon 
passing  westward  from  Fox  River  the  drift  increases  markedly  in  thickness 
witliin  the  township  limits,  though  the  elevation  remains  about  the  same. 
Several  instances  of  the  occun-ence  of  a  buried  soil  were  found  in  this 
townsliip  and  the  one  adjoining  it  on  the  west.  The  following  represent 
the  deepest  wells  in  T.  39,  R.  8  E.,  of  which  sections  were  obtained;  they 
are  all  at  an  altitude  of  about  750  feet: 

Wells  near  Batavia,  Illinois. 

In  sec.  4,  old  soil  at  120  to  126  feet,  gravel  at  bottom. 

East  part  of  Batavia  on  liluff,  rock  at  60  feet. 

Sec.  2i,  good  -n-ells  at  72,  81,  and  112  feet  in  drift. 

Mr.  Carr,  sec.  20,  well  strikes  rock  at  43  feet. 

Jlr.  Davenport,  sec.  19,  three  wells  in  drift  at  about  100  feet. 

Daniel  Frydendall,  sec.  31,  old  soil  at  80  feet;  depth  of  well  90  feet. 

In  T.  39,  R.  7  E.,  wells  are  usually  obtained  at  40  to  75  feet,  but  a  few 
exceed  100  feet.  The  following  embrace  the  deepest  of  which  sections 
wei-e  obtained: 

Wells  in  T.  39,  B.  7  E. 

Cheese  factory  at  La  Fox;  depth,  126  feet;  rock  at  65  feet. 

C.  G.  Morse,  sec.  3;  depth,  83  feet;  no  rock  struck;  lower  half  a  harder  till  than  the  upper. 

Mr.  Outhouse's  well,  north  of  Elbum;  altitude,  about  900  feet;  depth,  100  feet. 

Tile  factory  well  at  Elburn;  altitude,  850  feet;  depth,  70  feet;  old  soil  at  60  feet. 

C.  F.  Field,  sec.  10;  altitude,  800  feet;  depth,  96  feet;  rock  at  85  feet. 

P.  Washburn,  sec.  14 ;  altitude,  825  feet ;  depth,  169  feet.  The  well  is  on  a  gravel  knoll  50  feet  in 
height  and  penetrates:  Gravel  and  sand,  50  feet;  brown  till.  97  feet;  black  muck,  with  log 
embedded,  2i  feet ;  yellow  till,  7  feet;  sand  and  gravel,  with  water,  10  feet. 

Mr.  Sheets,  sec.  20 ;  altitude,  750  feet ;  depth,  47  feet ;  soil,  with  wood,  at  40  feet. 

Blackberry  P.  O.,  sec.  21 ;  well  from  gravel  below  till  at  70  feet. 

F.  S.  Morrill,  sec.  21;  altitude,  750  feet;  depth,  60  feet;  mainly  blue  till. 

Mr.  Kigling.  sec.  22;  altitude,  750  feet;  depth,  50  feet;  rock  at  bottom. 

D.  C.Greene,  sec. 22;  altitude,  750  feet;  depth,  40  feet;  wood  near  bottom. 

Johnson's  Mound,  sec.  15;  .altitude,  800  feet;  depth,  180  feet.  The  well  is  on  the  slope  of  a  knoll 
80  feet  above  bordering  plain.  Another  well  passed  through  a  bed  of  leaves  and  muck  at 
about  the  level  of  the  base  of  the  mound.     Neither  well  entered  rock. 

William  Beler,  sec.  17;  altitude,  750  feet;  depth,  46  feet;  rock  at  bottom. 

Annis  estate,  sec.  29;  altitude,  700  feet;  depth,  66  feet;  mainly  blue  till;  wood  and  black  nnick 
at  64  feet.     Well  is  thought  to  have  struck  rock  at  bottom. 

Russell  Benton,  sec.  30;  altitude,  700  feet:  depth,  75  feet;  entirely  in  gravel. 

In  the  vicinity  of  Kaneville,  as  noted  above,  there  is  a  delta-shaped 
jjlain  of  gravel  formed  at  the  western  end  of  an  esker  (see  PI.  XR^).  Near 
the  western  border  the  gravel  is  but  20  feet  in  depth,  but  at  the  eastern 
border,  near  the  esker,  wells  60  feet  in  depth  do  not  reach  the  bottom.     At 


WELLS  OP  KANE  COUNTY,  ILLINOIS.  599 

Kaneville  wells  liave  a  depth  of  35  or  40  feet  and  penetrate  both  gravel 
and  till.  At  Charles  Benton's,  east  of  Kaneville,  in  sec.  25,  a  well  54  feet 
in  depth  is  thonght  to  have  struck  rock.  It  penetrates  clay  25  feet,  sand 
25  feet,  gravel  4  feet.  Near  the  center  of  the  township,  in  sec.  15,  a  well 
on  a  knoll  is  entirely  in  gravel  to  a  depth  of  44  feet. 

In  Sugar  Grove  Township  the  thickness  of  drift  varies  from  16  feet  or 
less  up  to  fuU}^  75  feet.  In  the  village  of  Sugar  Grove  the  deepest  wells  are 
50  to  70  feet  without  entering  rock.  In  some  instances  they  are  through 
gravel  and  in  others  mainly  through  till.  A  well  at  Mr.  Hatch's,  in  sec.  7, 
70  feet  in  depth,  obtains  water  in  gravel  at  bottom  and  penetrates  alterna- 
tions of  clay  and  fine  sand.  Mr.  Dorr,  in  sec.  8,  has  a  well  in  a  basin  at 
the  side  of  an  esker  which  is  entirely  in  clay  to  a  depth  of  20  feet.  On 
the  borders  of  the  basin  the  drift  is  gravelly,  like  that  of  the  esker.  Mr. 
S.  E.  Sheppardson,  in  sec.  16,  has  a  well  75  feet  in  depth,  which  is  entirely 
through  sand  and  cemented  gravel.  Mr.  Chapman,  near  Sugar  Grove,  has 
a  well  90  feet  in  depth,  which  entered  rock  at  60  feet.  It  was  mainly 
through  till.  Mr.  Potter,  in  sec.  32,  has  a  well  on  a  knoll,  which  reaches  a 
depth  of  70  feet  without  entering  rock.  The  upper  40  feet  is  gravel  and 
sand;  the  remainder  is  sandy  till. 

At  Aurora  the  public  water  supply  is  from  a  series  of  deep  artesian 
wells  1,388,  2,270,  and  2,255  feet  in  depth.  The  first  obtains  water  from 
the  St.  Peter  and  the  others  from  the  Potsdam  sandstone.  The  water  has  a 
head  about  60  feet  above  the  surface,  or  710  feet  above  tide.  An  analysis 
of  the  water  from  each  well  appears  in  the  Seventeenth  Annual  Report  of 
this  Survey.^  The  water  from  the  St.  Peter  sandstone  contains  a  remarka- 
bly small  amount  of  saline  matter  and  is  of  excellent  quality  for  domestic 
use.  The  Potsdam  water  is  more  saline  than  the  water  from  the  St.  Peter 
sandstone.  Private  wells  are  obtained  in  Aurora  and  vicinity  at  about  40 
feet  in  gravel.  Rock  is  extensively  exposed  along  Fox  River  in  the  city 
and  below  as  far  as  the  county  limits. 

DEKALB  COUNTY. 
GENERAL    STATEMENT. 

Dekalb  County  is  situated  immediately  west  of  Kane  and  near  the 
middle  of  the  second  tier  of  counties  from  the  north.  It  has  an  area  of 
650  square  miles,  and  Sycamore  is  the  county  seat.     The  greater  portion  of 

I  Part  ir,  p.  820. 


600  ^  THE  ILLINOIS  GLACIAL  LOBE. 

the  county  drains  northward  through  the  south  fork  of  Kishwaukee  River. 
The  southeastern  jjart  is  tributary-  to  Fox  River.  Like  the  counties  to  the 
east,  it  is  so  imperfectly  drained  that  much  artificial  drainage  has  been  made, 
both  by  surface  ditches  and  by  tiling. 

The  Bloomington  morainic  system  which  crosses  the  central  portion  in 
a  northeast-southwest  direction  rises  about  100  feet  above  the  district  on  the 
outer  border.  There  is  on  the  imier  border  a  gTadual  descent  to  the  valley 
of  Fox  River  across  a  plain  dotted  with  only  occasional  knolls. 

The  di-ift  is  probably  as  heavy  as  in  any  of  the  counties  of  northern 
Illinois  (except  perhaps  Bureau  County),  there  being  in  22  borings  which 
reach  rock  an  average  thickness  of  151  feet,  while  68  other  deep  wells  which 
do  not  reach  rock  show  an  average  of  101  feet.  The  jaortion  on  the  north 
border  of  the  county  outside  the  morainic  system  has  scarcely  50  feet  of  drift, 
and  as  it  comprises  an  area  of  fully  100  square  miles  it  materiallv  reduces 
the  average  for  the  county.  As  in  the  counties  to  the  east,  the  drift  is  largely 
a  blue  till,  and  occasional  instances  of  the  occurrence  of  a  buried  soil  near 
or  perhaps  below  the  level  of  the  base  of  the  Wisconsin  di'ift  have  come  to 
notice. 

In  a  large  part  of  the  county  dairying  is  the  principal  pm-suit,  and 
many  deep  wells  have  been  sunk  to  supply  the  stock  or  to  furnish  water  for 
the  creameries  and  cheese  factories.  Many  of  these  wells  exceed  100  feet 
in  depth,  and  wells  200  feet  or  more  in  depth  are  not  I'are. 

INDIVIDUAL    ATELLS. 

In  the  northwest  townsliip  of  the  county  there  are  few  deep  wells, 
water  usually  being  obtained  at  25  to  40  feet.  A  well  in  sec.  36,  however, 
reached  a  depth  of  75  feet  without  entering  rock.  At  several  points  within 
the  township  the  rock  outcrops  at  a  level  not  more  than  25  feet  below  this 
well  mouth,  or  about  800  feet  above  tide.  A  flowing  well  in  sec.  35  is  sup- 
jjlied  from  gi-avel  below  till  at  a  depth  of  22  feet. 

In  T.  42,  R.  4  E.,  rock  outcrops  are  nearly  continuous  along  the  Kish- 
waukee  Bluft's  up  to  an  altitude  about  750  feet  above  tide.  A  few  wells  in 
the  vicinity  of  the  river  penetrate  40  feet  or  more  of  drift.  On  the  south 
border  of  the  township  there  is  a  rise  of  100  feet  or  more  to  the  niorainic 
system  refen-ed  to  above,  and  wells  here  exceed  100  feet  in  depth  without 
reaching  rock.     One  at  Mr.  Leander  Roberts's,  in  sec.  32,  has  a  depth  of  132 


WELLS  OF  DEKALB  COUNTY,  ILLmOIS.  601 

feet.  Another  in  the  same  section,  at  Mr.  Keague's,  has  a  depth  of  110 
feet. 

At  Genoa,  in  the  northeast  township  of  the  comity,  the  wells  are  25  to 
60  feet  in  depth  and  obtain  their  supply  from  gravel  below  till.  A  well  in  sec. 
26,  near  New  Lebanon,  at  an  altitude  about  850  feet  above  tide  enters  rock 
at  90  feet,  and  has  a  depth  of  122  feet.  The  south  border  of  this  township 
is  occupied  by  the  outer  moraine  of  the  Wisconsin  drift,  but  no  records  of 
deep  wells  were  obtained.  In  the  township  to  the  south,  however,  records 
of  several  wells  were  obtained  which  show  the  di'ift  to  reach  a  thickness  of 
150  to  200  feet  or  more. 

For  example,  in  sec.  9.,  T.  41,  R.  5  E.,  a  well  156  feet  in  depth  does  not 
reach  rock  and  is  mainly  through  blue  till.  The  altitude  is  about  900  feet. 
At  Mr.  Marshall's,  in  sec.  11,  at  a  similar  altitude,  a  well  has  a  depth  of  111 
feet.  At  John  Haine's,  in  sec.  2,  a  well  is  obtained  at  86  feet.  Near  the 
center  of  the  township,  in  sec.  15,  Mr:  E.  Devine  made  three  unsuccessful 
borings  for  water  to  a  depth  of  about  200  feet  without  reaching. the  bottom 
of  the  drift.  The  altitude  at  the  wells  is  about  875  feet.  Four  wells  in  sec. 
25  each  have  a  depth  of  about  125  feet,  and  a  fifth  well  has  a  depth  of  170 
feet.  They  are  all  mainly  through  blue  till,  and  none  enter  the  rock.  In 
sees.  35  and  36  three  wells  have  a  depth  of  about  100  feet,  a  fourth  has 
a  depth  of  148  feet,  and  a  fifth  a  depth  of  151  feet,  all  mainly  tlu'ough 
blue  till. 

In  T.  41,  R.  4  E.,  records  of  wells  show  the  depth  of  dt-ift  to  exceed 
100  feet,  while  one  well  in  sec.  31  reaches  a  depth  of  113  feet  without 
reaching  rock.  This  well  is  thought  to  have  passed  through  an  old  soil  at 
about  80  feet.  Another  well  in  the  same  section  has  a  depth  of  112  feet. 
The  wells  of  this  township  are  mainly  through  blue  till,  but  one,  in  sec.  11, 
is  reported  to  have  passed  tlnough  35  feet  of  yellow  till  and  10  feet  of  sand 
before  entering  blue  till.  The  well  has  a  depth  of  98  feet,  and  terminates 
in  a  cemented  gravel. 

A  portion  of  township  41,  R.  3  E.,  is  outside  the  above-mentioned 
morainic  system  and  wells  there  are  seldom  more  than  80  feet  in  depth.  A 
well  at  Dustin  post-office,  77  feet  in  depth,  is  reported  to  have  struck  rock 
near  the  bottom.  Another,  in  sec.  8,  76  feet  in  depth,  penetrates  about  2  feet 
of  rock  at  bottom.  At  a  schoolhouse  in  this  section,  however,  a  well  strikes 
rock  at  12  feet.     The  altitude  at  each  of  these  wells  is  about  825  feet 


602  THE  ILLINOIS  GLACIAL  LOBE. 

above  tide.  At  Deerfield  post-office  an  old  soil  was  found  beneath  the  blue 
till  at  a  depth  of  35  or  40  feet.  As  this  stands  outside  the  Wisconsin  drift 
sheet,  the  soil  is  to  be  refen-ed  to  an  earlier  interg-lacial  stage  than  that 
immediately  preceding  the  Wisconsin  stage  of  glaciation,  probably  the 
Sangamon  stage.  A  well  on  the  moraine  in  sec.  27,  about  75  feet  higher 
than  Deei-field,  enters  a  black  soil  at  a  depth  of  125  to  130  feet,  or  at 
nearly  the  same  level  as  that  at  Deei'field,  and  perhaps  to  be  refen-ed  also 
to  the  Sangamon  interglacial  stage.  The  following  records  of  deep  wells 
were  obtained  along  the  moraine  in  the  southeast  part  of  this  township: 

Wells  in  T.  41,  B.  3  E. 

Feet. 

Mr.  Casey,  sec.  13,  altitude  87.5  feet 130 

John  Lloyd,  sec.  27,  altitude  TOO  feet 130 

Sergis  Lloyd,  sec.  34,  altitude  900  feet 190 

James  Gibson,  sec.  23,  altitude  850  feet .♦. 90 

James  Renwick,  sec.  28,  altitude  900  feet,  enters  rock  at  230  feet 230 

In  T.  40,  R.  3  E.,  a  well  in  sec.  3,  183  feet  in  depth,  enters  rock  at 
176  feet.  The  altitude  of  the  well  mouth  is  about  900  feet.  A  well  in 
sec.  20,  109  feet  in  depth,  is  reported  to  have  passed  tlu-ough  a  black  soil 
near  the  bottom.  The  altitude  is  about  875  feet.  A  well  a  mile  east  from 
this  reached  a  depth  of  123  feet. 

In  T.  40,  R.  4  E.,  records  of  several  wells  which  reach  rock  were 
obtained.  One  at  Mr.  Barlow's,  in  sec.  31,  153  feet  in  depth,  enters  rock  at 
140  feet.  One  at  Mi*.  Gui-ler's,  in  sec.  32,  also  enters  rock  at  about  140 
feet.  The  altitude  at  these  wells  is  860  to  875  feet.  A  well  at  William 
Barr's,  in  sec.  31,  at  similar  altitude,  failed  to  reach  rock  at  183  feet.  At 
Dekalb  one  of  the  artesian  wells  reaches  rock  at  126  feet,  another  at  195 
feet,  and  another  at  309  feet.  South  of  Dekalb,  in  sec.  33,  a  well  enters 
rock  at  225  feet.  The  altitude  of  these  wells  in  the  vicinity  of  Dekalb  is 
between  865  and  900  feet.  Records  were  obtained  of  seven  wells  between 
Dekalb  and  Malta  having  a  depth  of  about  100  feet  each,  and  one  well 
having  a  depth  of  150  feet,  none  of  which  enter  rock. 

The  city  water  supply  of  Dekalb  is  obtained  from  a  well  890  feet  in 
depth,  wliich  terminates  in  the  St.  Peter  sandstone.  Several  other  deep 
wells  have  been  made  in  the  city  wliicli  terminate  in  that  sandstone.  A 
well  at  the  public  square  was  drilled  to  a  depth  of  2,470  feet  and  terminated 
in  the  Potsdam  sandstone.  Mr.  Elwood  sunk  a  well  neai*  Dekalb  to  a 
depth  of  700  feet.     None  of  the  wells  mentioned  overflow.     The  well  at 


WELLS  OF  DEKALB  COUNTY,  ILLmOIS. 


603 


the  city  waterworks  stands  about  65  feet  below  the  surface.  It  is  prob- 
able that  all  obtain  water  from  horizons  above  the  St.  Peter  as  well  as  from 
that  sandstone.  The  well  at  the  public  square  penetrated  till  145  feet, 
below  which  there  was  50  feet  of  sand  and  gravel.  The  well  in  sec.  33, 
noted  above,  penetrated  a  till,  mainly  of  bluish  color,  145  feet;  sand,  20 
feet;  blue  till,  59  feet.  Mr.  El  wood's  well  had  about  100  feet  of  till  at 
surface;  the  remaining  200  feet  was  mainly  sand  and  gravel. 

The  city  water  supply  at  Sycamore  is  obtained  from  several  flowing 
wells,  which  obtain  water  at  a  depth  of  about  65  feet,  from  gravel  beds 
below  blue  till.  There  are  several  other  flowing  wells  of  similar  depth  along 
the  Kishwaukee  River  Valley  in  the  vicinity  of  Sycamore.  Wells  are  usu- 
ally obtained  in  this  township  at  depths  of  50  to  85  feet,  there  being  appar- 
ently a  sheet  of  gravel  and  sand  below  blue  till  at  this  honzon. 

In  the  western  part  of  Dekalb  County,  in  T.  39,  Rs.  3  and  4  E., 
several  wells  have  been  sunk  to  the  rock,  as  follows: 

Wells  in  western  JDelcalb  County  that  reach  rock. 


Locality. 


Altitude. 

Depth. 

Feet. 

Feet. 

875 

224 

900 

170 

900 

260 

925 

228 

925 

200 

890 

162 

925 

175 

925 

199 

860 

140 

In  sec.  1,  T.  39,  K.  3  E 

Wm.  Keast,  sec.  4,  K.  3  E 

Holton  Brue,  sec.  11,  R.  3  E 

Theodore  Burgh,  sec.  19,  K.  3  E  . . . 
Theodore  Burgh,  sec.  19,  E.  3  E  . . , 

John  Watson,  sec.  28,  R.  3  E , 

A.  W.  Howard,  sec.  20,  R.  3  E 

Andrew  Nicholson,  sec.  20,  R.  3  E 
H.  Gerler,  sec.  5,  T.  39,  R.  4  E 


All  these  wells,  with  the  exception  of  Mr.  Nicholson's,  terminated  after 
penetrating  rock  less  than  10  feet.  But  Mr.  Nicholson's  had  penetrated  25 
feet  of  rock  at  the  depth  above  given.  A  boring  in  sec.  7,  T.  39,  R.  3  E., 
at  an  altitude  about  925  feet,  reached  a  depth  of  230  feet  without  entering 
rock  or  obtaining  water.  Another  boring  on  the  same  farm  obtained  water 
in  gravel  at  a  depth  of  192  feet.  A  well  in  sec.  9  obtained  water  in  gravel 
at  a  depth  of  172  feet. 

In  T.  38,  R.  3  E.,  a  well  in  sec.  8  strikes  rock  at  152  feet,  though 
located  on  an  elevated  jDart  of  the  moraine  nearly  950  feet  above  tide. 
Several  other  tubular  wells  in  that  vicinity  reach  rock  at  depths  of  less 


604  THE  ILLINOIS  GLACIAL  LOBE. 

than  200  feet,  but  one  well  reached  a  depth  of  212  feet  without  encoun- 
teiing  rock.  Two  wells  in  the  west  pai-t  of  the  township,  on  the  farms  of 
Taylor  Thompson  and  William  Storey,  at  altitudes  about  9.50  feet,  struck 
an  inflammable  gas  in  gravel  at  depths  of  125  to  150  feet.  The  drift  is 
mainly  till  above  this  gravel.  Strong  wells  are  obtained  from  gravel  in 
that  vicinity  at  100  to  150  feet. 

On  the  plain  in  the  southeast  part  of  the  county  wells  are  usually 
obtained  at  depths  of  30  or  40  feet.  The  railroad  well  at  Hinckley,  how- 
ever, was  sunk  to  a  depth  of  190  feet  and  entered  rock  at  about  100  feet. 
The  altitude  is  750  feet  at  this  well.  At  Sandwich,  where  the  altitude 
is  only  655  feet,  the  wells  for  the  public  water  supply  are  sunk  to  a  depth 
of  113  feet  without  entering  rock.  Several  tubular  wells  are  driven  in  the 
bottom  of  a  large  well.  Private  wells  in  Sandwich  and  vicinity  usually 
obtain  an  abundant  supply  at  about  30  feet. 

In  the  southwest  part  of  the  county  several  flowing  wells  have  been 
obtained  from  the  drift  at  depths  of  less  than  30  feet.  Ten  such  wells  have 
been  made  on  sec.  32,  T.  37,  R.  3  E.,  whose  depths  are  but  22  to  27  feet. 
A  well  in  sec.  31  is  24  feet.  The  altitude  at  these  wells  is  about  725  feet 
above  tide.  This  flowing  well  district  extends  southward  to  Earlville  in 
Lasalle  County.  The  absorption  area  is  probably  from  the  moraine  on 
the  northwest.  A  well  in  sec.  2,  T.  37,  R.  3  E.,  67  feet  in  depth,  passed 
throus'h  an  old  soil  at  55  to  60  feet.  The  altitude  at  the  well  is  about 
800  feet. 

OGLE    COUNTY. 
GENERAL   STATEMENT. 

Ogle  County  is  situated  west  of  the  northern  part  of  Dekalb  County, 
and  south  of  Winnebago  and  Stephenson  counties.  It  has  an  area  of  780 
square  miles,  and  Oregon  is  the  county  seat.  Rock  River  traverses  the 
county  nearly  centrally  in  a  course  west  of  south,  and  the  county  is  drained 
by  small  tributaries  of  that  stream.  The  greater  part  of  the  county  is 
covered  but  thinly  with  drift,  and  preglacial  ridges  and  valleys  are  in  many 
cases  readily  traced.  The  outer  moraine  of  the  Wisconsin  drift  touches  the 
southeast  corner  of  the  county,  and  the  drift  there  is  250  feet  or  more  in 
thickness.  The  large  jjreglacial  ^■alle3•,  thought  to  be  the  old  course  of 
Rock  River,  traverses  the  eastern  part  of  the  county  in  a  north  to  south 


WELLS  OF  OGLE  COUNTY,  ILLINOIS.  605 

direction.  It  is  filled  nearly  to  the  level  of  the  bluffs,  and  judging  by  the 
distance  to  rock  in  portions  of  the  valley  to  the  north  and  south,  thei-e  is 
probably  not  less  than  400  feet  of  drift  filling.  Along  the  present  course 
of  Eock  River  there  are  continuous  bluffs  rising  to  heights  varying  from 
75  up  to  fully  200  feet. 

On  the  uplands,  in  fully  three-fourths  of  the  countj^,  wells  commonly 
enter  the  rock  at  10  to  40  feet,  and  obtain  water  at  depths  ranging  from  50 
feet  up  to  about  300  feet.  Along  the  lines  of  preglacial  valleys  water  is 
usually  obtained  at  a  shallow  depth  in  gravel.  There  are  belts  of  gravelly 
drift  of  esker  type  in  the  western  part  of  this  county  similar  to  those  in 
Stephenson  County  on  the  north,  and  with  a  similar  east  to  west  trend. 
Aside  from  these  gravelly  strips  the  drift  is  usuall}^  a  compact  till.  There  are,- 
however,  as  in  Stephenson  and  Winnebago  counties,  many  places  where  it 
is  made  up  largely  of  coarse  stony  material.  In  the  portion  outside  the 
Wisconsin  drift  there  are  two  drift  sheets  of  widely  different  age.  The 
later  of  these,  the  lowan,  appears  to  extend  but  little  west  of  Eock  Eiver, 
thus  leaving  only  the  lUinoian,  in  the  western  part  of  the  county,  unless  a 
sheet  older  than  Illinoian  is  found  to  be  present. 

INDIVIDUAL   WELLS. 

In  the  northwest  part  of  the  county,  in  the  vicinity  of  Foreston,  a  till 
sheet  30  to  40  feet  in  thickness  is  generally  present.  Some  of  the  wells  are 
obtained  without  entering  the  rock,  but  the  stronger  wells  are  usually 
drilled  into  the  limestone.  The  public  water  supply  at  Foreston  is  obtained 
from  a  well  300  feet  in  depth,  in  which  water  rises  within  20  feet  of  the 
surface.     The  private  wells  are  35  to  80  feet  in  depth. 

At  Mount  Morris  the  public  supply  is  from  a  well  502  feet  in  depth, 
whose  head  is  nearly  200  feet  below  the  surface  and  near  the  top  of  the  St. 
Peter  sandstone. 

At  Adeline  the  drift  is  gravelly,  the  village  being  situated  on  a  plexus 
of  knolls  and  ridges  associated  with  an  esker  which  leads  westward  along 
Leaf  Eiver.     Wells  here  obtain  water  at  depths  of  30  to  75  feet  in  gravel. 

At  Hazelhurst,  on  the  west  border  of  the  county,  there  is  an  esker  in 
which  a  well  was  sunk  to  a  depth  of  135  feet  before  striking  rock,  though 
the  well  mouth  is  50  feet  below  the  highest  part  of  the  esker.     Between 


606  THE  ILLINOIS  GLACIAL  LOBE. 

Hazellmrst  and  Polo  rock  is  usualh-  entered  at  2U  feet  or  less  and  the  drift 
is  of  ^•ariable  constitution,  there  being  abrupt  changes  from  gravel  or  sand 
to  till.  There  is  a  general  capping  of  loess  in  that  vicinity  6  or  7  feet  in 
depth. 

The  public  water  supply  at  Polo  is  obtained  from  a  well  2,100  feet 
in  depth,  which  terminates  in  the  Potsdam  sandstone.  It  is  situated  in 
a  creek  valley,  and  has  but  37  feet  of  drift.  The  water  is  of  pleasant 
taste  and  is  obtained  in  sufficient  quantity  for  the  needs  of  the  town.  A 
well  at  French's  tile  yard  at  Polo  penetrates  about  80  feet  of  drift.  The 
upper  13  feet  is  loess  and  sandy  material,  but  the  remainder  is  a  compact 
till.  East  of  Polo,  on  the  divide  between  Elkhorn  and  Pine  creeks,  there 
are  several  wells  which  penetrate  about  60  feet  of  di-ift.  The}"  are  in  a 
blue  till  from  20  feet  downward  to  the  rock. 

At  Stratford  the  village  well  is  45  feet  in  depth  without  entering  rock. 
The  railway  cuttings  immediately  east  of  this  village  expose  two  sheets  of 
till  separated  b}'  a  fossiliferous  silt.  The  upper  sheet  as  stated  above  (p.  138) 
is  apparentl}"  much  younger  than  the  lower  and  is  probabl}"  of  lowan  age. 
Within  a  mile  east  of  Stratford  rock  ledofes  occur  at  an  elevation  as  hig-h  as 
the  railway  station  (820  feet). 

At  Oregon  the  wells  range  in  depth  from  20  to  fully  200  feet,  but  are 
usually  about  30  feet.  The  public  water  supply  was  pumped  from  Eock 
River  until  recently,  but  the  Manual  of  American  Waterworks  (1897) 
reports  the.  present  supply  to  be  from  wells.  A  railway  cutting-  between 
Oregon  and  Mount  Morris  exposes  a  buried  soil  below  till  at  a  depth  of 
about  25  feet.  This  probably  separates  the  lowan  from  the  lUinoian  till 
sheet. 

At  the  village  of  Grand  Detom*  wells  on  a  terrace  in  the  ^'allev  of 
Rock  River  obtain  water  in  g-ravel  at  a  depth  of  20  feet. 

At  the  village  of  Byron,  which  is  situated  on  a  terrace  standing  about 
50  to  55  feet  above  Rock  River,  wells  are  usually  sunk  through  a  gravelly 
sand  to  the  level  of  the  ri^-er. 

In  the  vicinity  of  Stilhuan  Valley  the  drift  is  gravelly,  and  wells  are 
usually  obtained  at  a  depth  of  25  feet  or  less.  On  the  uplands  bordering 
the  valley  in  which  this  village  is  situated  rock  is  usually  struck  at  a  depth 
of  10  or  15  feet. 


WELLS  OF  OGLE  COUNTS,  ILLINOIS.  607 

At  Davis  Junction  a  town  well  53  feet  in  depth  enters  rock  at  18  feet, 
and  the  rock  outcrops  in  many  places  toward  the  south.  West  and  north 
from  Davis  Junction  wells  usually  penetrate  50  to  80  feet  of  drift.  A  well 
made  by  F.  H.  Baker,  1^  miles  west  of  Davis  Junction,  is  190  feet  in  depth 
and  strikes  rock  at  about  80  feet.  Northeast  and  east  from  this  village  wells 
reach  a  depth  of  over  100  feet  without  entering  rock,  this  being  the  position 
of  the  old  valley  of  Rock  River  referred  to  above.  The  deepest  well  noted 
is  at  Mr.  Kerr's,  in  sec.  11,  which  obtains  water  from  gravel  at  a  depth  of 
120  feet.  There  appears  to  be  a' heavy  sheet  of  till  along  this  preglacial 
valley,  wells  80  to  120  feet  in  depth  being  mainly  tln-ough  that  deposit. 

At  Monroe,  which  is  situated  on  the  east  side  of  the  old  Rock  River 
Valley,  rock  is  usually  struck  at  5  or  10  feet,  but  Mr.  Tyler's  well  pene- 
trated 44  feet  of  di-ift  before  entering'  rock.  The  railway  cutting  immediately 
west  of  Monroe  also  exposes  drift  to  a  depth  of  over  30  feet. 

Records  of  sevei'al  wells  were  obtained  in  sees.  27,  28,  29,  30,  31,  32, 
33,  and  34,  T.  42,  R.  2  E.,  which  are  about  30  feet  in  depth,  and  but  one 
well  enters  rock.  East  from  these  sections  as  far  as  the  county  line  rock  is 
usually  entered  at  a  depth  of  10  to  20  feet. 

Two  wells  in  sec.  2,  T.  41,  R.  2  E.,  enter  an  old  soil  below  till  at  a 
depth  of  20  to  22  feet,  which  is  thought  to  separate  the  lowan  sheet  from 
an  underlying  older  one.  This  soil  in  all  probability  represents, the  Sanga- 
mon interglacial  stage.  About  2  miles  south  from  these  wells,  at  James 
Ashbrook's,  a  black  muck  was  struck  at  67  feet,  which  yields  an  inflammable 
gas.  The  altitude  at  each  of  these  wells  is  about  780  feet  above  tide  and 
the  biu-ied  soils  are  probably  all  referable  to  the  same  stage. 

In  the  vicinity  of  Lindenwood  rock  is  struck  at  slight  depth  (12  to  25 
feet).  The  preglacial  valley  of  Rock  River  appears  to  lie  entirely,  north 
and  east  of  this  village.  A  well  at  William  Stocking's,  near  this  village,  in 
sec.  1,  T.  41,  R.  1  E.,  reached  a  depth  of  100  feet  without  entering  rock. 
It  is  probably  over  the  line  of  a  tributary  of  the  Rock  River  Valley,  for 
neisrhborino-  wells  enter  rock  at  12  to  30  feet. 

In  the  vicinity  of  Kings  Station,  and  thence .  westward  past  Paines 
Point,  wells  usually  enter  rock  at  about  10  feet  and  obtain  water  at  30  to 
50  feet. 

At  Rochelle  the  public  water  supply  is  obtained  from  springs  issuing 
from  an  old  rock  quarry.     Wells  are  usually  obtained  at  30  or  40  feet  and 


608  THE  ILLIISrOIS  GLACIAL  LOBE. 

enter  limestone  at  about  10  feet.     The  old  valley  of  Rock  River  passes  east 
of  tliis  city. 

At  Creston,  which  is  situated  on  the  outer  moraine  of  the  Wisconsin 
drift,  a  well  at  the  tile  factory,  256  feet  in  depth,  enters  rock  at  250  feet. 
Several  other  wells  in  this  village  and  vicinity  are  150  feet,  but  probably 
the  majorit}"  of  wells  average  not  more  than  50  feet.  They  are  mainly 
through  a  soft  blue  till. 

LEE  COUNTY. 
GENERAL    STATEMENT. 

Lee  County  is  situated  south  of  Ogle  and  west  of  the  southern  portion 
of  Dekalb.  It  has  an  area  of  740  square  miles,  and  Dixon  is  the  county 
seat.  Rock  River  crosses  the  northwest  corner,  but  drains  by  direct  tribu- 
taries only  a  small  portion  of  the  county.  The  central  and  southwestern 
portions  drain  into  Green  River,  the  main  southern  tributary  of  Rock  River. 
The  southeastern  portion  of  the  county  is  drained  by  Bureau  Creek,  a 
tributary  of  the  Illinois.  The  portion  drained  by  Green  River  is  largely  a 
marsh,  but  artificial  drainage  has  brought  much  of  it  under  cultivation. 

The  outer  morainic  system  of  the  Wisconsin  drift  occupies  the  eastern 
and  southern  borders  of  the  county,  and  stands  100  to  150  feet  or  more 
above  the  neighboring  portions  of  the  Green  River  marsh  on  its  outer 
border.  The  preglacial  Rock  River  apparently  passed  tln-ough  this  portion 
of  the  county.  It  is  probable  that  where  the  elevated  portions  of  the 
moraine  coincide  with  this  old  valley  there  is  not  less  than  600  feet  of  drift, 
the  rock  floor  of  the  old  valley  being  known  to  be  at  a  level  that  much 
Ijelow  the  crest  of  the  moraine.  Northwestward  from  the  Green  River 
marsh  the  drift  is  generally  of  slight  depth,  many  wells  entering  rock 
at  25  feet  or  less,  while  outcrops  of  the  limestone  are  common  on  nearly 
all  the  streams  in  that  part  of  the  county. 

Wells  are  usually  obtained  at  moderate  depths  in  the  rock,  seldom 
more  than  50  feet.  On  the  moraine  in  the  eastern  and  southern  portion  of 
the  county  the  wells  in  several  instances  exceed  200  feet  in  depth  without 
entering  rock,  and  in  portions  of  the  Green  River  marsh  the  drift  is  known 
to  exceed  200  feet.  The  usual  depth  of  wells  on  the  moraine  is,  however, 
not  more  than  100  feet,  there  being  considerable  sand  and  gravel  associated 
with  the  till  which  forms  the  body  of  the  drift. 


WELLS  OF  LEE  COUNTY,  ILLINOIS.  609 

INDIVIDTIAL    WELLS. 

At  Dixon  the  public  water  supply  is  obtained  from  three  artesian  wells, 
1,637,  1,710,  and  1,810  feet  in  depth,  which  terminate  in  the  Potsdam 
sandstone.  The  wells  overflow  into  a  reservoir,  from  which  the  water  is 
pumped  to  a  standpipe.  An  analysis  of  the  water,  published  in  the  Seven- 
teenth Annual  Report  of  this  Survey,^  shows  a  very  small  amount  of  salt 
and  a  moderate  degree  of  hardness.  The  water  is  considered  of  pleasant 
taste  and  excellent  quality.  The  wells  are  cased  only  about  50  feet.  The 
water  in  each  well  has  a  temperature  55°  F. 

At  Nachusa  wells  are  usually  obtained  at  about  30  feet  without  entering 
rock.  A  well  one  mile  northwest  of  the  village  reached  a  depth  of  95  feet 
without  striking  rock.  Within  a  half  mile  of  this  well,  however,  rock 
outcrops  at  a  higher  elevation  than  the  well  mouth. 

At  Franklin  Grove,  and  also  at  Ashton,  wells  usually  enter  rock  at  30  or 
40  feet,  and  there  are  numerous  outcrops  of  rock  in  that  vicinity.  In  several 
instances  coal  has  been  found  in  the  drift  in  the  vicinity  of  Ashton.  As  this  point 
is  north  of  the  border  of  the  coal  field,  it  suggests  a  noi'thwestward  movement 
of  the  ice  in  this  region,  though  the  occurrence  of  coal  here  may  perhaps  be 
due  to  the  presence  of  outliers  north  of  the  main  coal  field.  As  indicated 
below,  coal  apparently  underlies  the  southeast  corner  of  this  county. 

The  drift  is  thin  over  the  southern  half  of  T.  39,  R.  1  E.,  and  northern 
half  of  T.  38,  R.  1  E.,  but  north  and  east  from  this  locality  wells  occasion- 
ally reach  depths  of  50  and  even  100  feet  without  entering  rock.  The 
deepest  section  of  such  a  well,  noted  in  T.  39,  is  that  of  Robert  Peile,  in 
sec.  23,  which  reached  a  depth  of  108  feet.     The  well  has  the  following 

section : 

Section  of  Peile  well  in  T.  39,  R.  1  E. 

Feet. 

Soil  and  brown  till 10 

Gravel 1 

Blue  till 20 

Gravel 5 

Brownish  till,  with  occasional  gravellj'  beds 72 

The  upper  36  feet  of  this  section  should  perhaps  be  referred  to  the 
lowan  stage  of  glaciation.  Blue  till  is  occasionally  entered  in  that  vicinity 
at  only  6  or  7  feet  below  the  surface,  or  at  a  much  shallower  depth  than  in 
the  drift  of  the  Illinoian  stage. 

I  Part  II,  p.  827. 
MON  XXXVIII 39 


610 


THE  ILLINOIS  GLACIAL  LOBE. 


At  Amboy  shallow  wells  are  obtained  at  12  to  20  feet,  many  of  which 
enter  the  rock.  At  the  waterworks  the  supply  is  obtained  from  an  artesian 
well  2,000  feet  in  depth.  Water  veins  which  ovei-flow  were  struck  at  390, 
1,100,  and  1,700  feet.  The  lower  veins  do  not  increase  the  head,  but  evi- 
dently increase  the  quantity,  for  the  upper  flows  could  be  readily  lowered 
by  pumping,  while  the  lower  ones  can  not. 

The  discussion  of  wells  on  the  moraine  which  •follows  begins  in  the 
northeast  jjart  of  the  county,  from  which  point  the  moraine  is  followed 
southwestward. 

Table  of  deep  wells  in  eastern  and  southern  Lee  County,  Illinois. 


Location. 


Sec.  3,  T.  39,  R.  2  E 

Sec.  34,  T.  39,  K.  2  E 

Sec.  32,  T.  39,  R.  2  E 

Sec.  15,  T.  38,  R.  2  E 

Sec.  12,  T.  38,  R.  2  E 

Sec.  16,  T.  38,  R.  2  E 

Sec.  14,  T.  38,  R.  2  E 

Sec.  36,  T.  38,  R.  2  E 

Sec.  33,  T.  38,  R.  1  E 

Sec.  18,  T.  37,  R.  2  E 

3  miles  S.  of  Pawpaw  . . . 


Sec.  36,  T.  37,  R.  2  E 

Sec.  35,  T.  37,  R.  2  E 
Sec.  19,  T.  37,  R.  2  E 


Sec.  32,  T.  37,  R.  2  E  . . . . 
Sec.  30.  T.  38,  R.  1  E  . . . . 
Sec.  29,  T.  38,  R.  1  E  . . . . 
Sec.  12,  T.  19,  R.  HE  ... 

Sec.2,T.  19,R.8E 

Sec.  36,  T.  19,  R.  8  E  . . . . 


Sec.  14,  T. 20,  R.  8  E  .... 

Sec.  28,  T.  20,  R.  8  E  .... 


Altitude    ;    r,„„*v 
(above tide).!    ^'^P*''- 


Feet. 


800 

775 
950 


t. 

Feet. 

925 

168 

925 

200 

875 

45 

950 

200 

950 

50 

875 

40 

875 

60 

950 

217 

820 

114 

800 

115 

800 

100 

Remarks 


155 

100 
287 


925 

200 

800 

84 

800 

90 

935 

218 

660 

200 

800 

200 

700 

105 

690 

166 

In  gravel  below  till. 

Old  soil  at  100  feet ;  no  rock  struck. 

Gravel  below  till. 

Gravel  below  till. 

Gravel  below  till. 

Entirely  in  gravel. 

Mainly  sandy  drift. 

In  gravel  belovr  till;  no  rock. 

No  rock ;  old  soil  at  80  feet. 

Driller  reports  coal  at  bottom. 

Driller  reports  buried  soil  at  80  feet,  sandstone  at 

90  feet,  and  coal  at  about  100  feet. 
Old  soil  at  78  to  81  feet;  drift  mainly  till;  no  rock 

struck. 
Mainly  sand  and  gravel ;  no  rock. 
Old  well,  45  feet;  sand,  5  feet;  blue  till,  190  feet; 

greenish  clay,  19  feet;  rock  (?),  6  feet;  blue  till, 

15  feet;  cemented  gravel,  li  feet;  loose  gravel  at 

bottom. 
Not  known  whether  rock  was  struck. 
Soil  and  wood  near  bottom. 
Wood  ami  leaves  at  bottom. 
Little,  if  any,  rock  penetrated. 
No  rook  struck. 
Terminates  in  sand.     Wood,  with  inflamniablo  gas, 

at  110  feet. 
No  rock;  beds  of  sand  and  gravel  in  blue  till. 
No  rock  struck;  sand,  25  feet;  remainder  blue  till. 


WELLS  OF  CARROLL  COUKTY,  ILLINOIS,  611 

The  last  edition  of  the  Manual  of  American  Waterworks  (1897)  reports 
that  the  village  of  Pawpaw,  in  the  southeast  part  of  the  county,  obtains  its 
public  supply  from  an  artesian  well  1,018  feet  in  depth. 

CARROLL    COUNTY. 
GENERAL    STATEMENT. 

Carroll  County  borders  the  Mississippi  River  in  the  second  tier  of 
counties  from  the  north  and  has  an  area  of  440  square  miles,  with  Mount 
Carroll  as  the  county  seat.  The  northwestern  portion  is  drained  by  Plum 
River  and  Carroll  Creek,  its  main  tributary,  directly  to  the  Mississippi 
Valley  at  Savanna.  The  southeastern  portion  is  di-ained  southward 
through  Rock  and  Elkhorn  creeks  into  Rock  River.  The  surface  is  rolling 
and  drainage  good  throughout  the  upland  portion  of  the  county. 

With  the  exception  of  the  northwest  corner,  which  is  ung-laciated,  this 
county  is  covered  with  a  sheet  of  drift  of  moderate  depth.  Records  of  14 
wells  on  the  uplands,  distributed  widely  over  the  county,  show  an  averag-e 
of  54  feet  to  the  rock,  the  greatest  depth  being  about  100  feet.  In  the 
Mississippi  Valley  below  Savanna  there  is  probably  150  feet  or  more  of 
drift,  as  indicated  by  borings  at  Sabula,  Iowa,  and  Fulton,  Illinois,  which 
reach  a  level  nearly  150  feet  below  the  Mississippi  before  entering  rock. 
The  valley  di-ift  is  lai'gely  sand  or  fine  gi-avel.  The  drift  on  the  uplands  is 
in  places  a  gravelly  or  stony  material,  but  usually  has  a  large  clay  admix- 
ture, such  as  characterizes  the  typical  till. 

In  every  township  of  the  uplands  numerous  wells  enter  the  rock,  but 
a  still  larger  number  obtain  water  from  gravel  or  sand  associated  with  till 
at  various  depths  from  20  feet  or  less  up  to  about  100  feet. 

INDIVIDUAL   WELLS. 

At  Savanna  the  public  water  supply  is  from  an  artesian  well  1,430 
feet  in  depth,  which  terminates  in  the  Potsdam  sandstone.  It  discharges  at 
the  rate  of  500  gallons  per  minute  and  has  a  pressure  of  35  pounds  per 
square  inch  at  the  level  of  the  well  mouth,  about  600  feet  above  tide.  The 
head  is,  therefore,  about  675  feet. 

At  Mount  Carroll  the  public  water  supply  is  from  a  well  2,502  feet 
in  depth,  which  has  a  head  sufficient  to  rise  nearly  to  the  well  mouth, 
about  700  feet  above  tide.     Water  was  struck  in  the  limestone  at  65  to  100 


612  THE  ILLINOIS  GLACIAL  LOBE. 

feet,  but  a  much  stronger  supply  was  struck  at  about  1,200  feet.     The  drift 

is  largely  gravel  aud  has  a  depth  of  61  feet      The  well  is  situated  in  a 

valley  about  100  feet  below  the  bordering  uplands,  and  rock  appears  in  the 

uplands  near  by  at  a  level  fully  50  feet  above  the  well  mouth.     A  well  at 

the  railway  station  in  Mount  CaiToll  reaches  rock  at  a  depth  of  60  feet. 

The  altitude  there  is  816  feet  above  tide.     This  well  penetrated  a  complex 

series  of  beds  of  gravel,  sand,  and  till.     A  boring  at  William  Petty's,  4 

miles  southwest  of  Mount  Carroll,  is  reported  to  have  penetrated  about  300 

feet  of  drift.     On  the  farm  of  R.  Hostetter,  3  miles  southeast  of  Mount 

CaiToll,  a  well  strikes  rock  at  the  depth  of  72  feet;  the  drift  is  mainly  a 

blue  clay.     Hon.  James  Shaw  reports  a  well  section  near  Mount  Carroll, 

which  sti'uck  a  black  mucky  clay,  apparently  a  soil,  at  a  depth  of  about  50 

feet;  another  well  at  the  farm  of  F.  O'Neal,  3  miles  from  Mount  Can-oil, 

passed  through  a  soil  and  wood  at  15  to  20  feet.     The  latter  is  perhajDS  at 

the  junction  of  the  loess  with  the  underlying-  glacial  di'ift,  but  the  former 

penetrated  a  sheet  of  glacial  di'ift  above  the  soil,   and  its   section  is  as 

follows :  ^ 

Section  of  a  well  near  Mount  Carroll,  Illinois. 

Feet. 

Soil,  yellow  and  blue  clays 15 

Eeddish  clay  and  gravel 15 

Tough  blue  clay 2 

Coarse  gravel •- 3 

Yellow  sand 11 

Black  mucky  clay 5 

A  deep  artesian  well  has  been  sunk  in  a  creek  valley  about  4  miles 
south  of  Mount  Carroll,  which  overflows  with  considerable  force.  No 
further  data  have  been  olitained. 

At  Lanark  the  public  water  supply  is  from  a  well  obtained  near  the 
top  of  the  limestone  at  about  100  feet.  The  following  drift  beds  were 
penetrated:  Clay,  12  or  15  feet;  gravel  and  sand,  12  or  15  feet;  blue  clay, 
with  few  pebbles,  75  feet.  A  well  at  L.  Sprecher's,  1  mile  west  of  Lanark, 
enters  rock  at  about  100  feet  and  there  obtains  water.  In  the  township 
east  of  Lanark  wells  are  reported  to  differ  greatl}^  within  short  distances  in 
the  amount  of  drift  penetrated,  some  entering  rock  at  about  20  feet  while 
others  penetrate  100  feet  or  more  of  drift. 

'  Geology  of  lUinois,  Vol.  V,  p.  80. 


WELLS  OF  CARROLL  COUNTY,  ILLIN31S.  613 

At  Shannon  wells  near  the  railway  station  enter  rock  at  15  or  20  feet, 
but  on  a  rock  ridge  in  the  sonth  part  of  the  village,  at  an  elevation  proba- 
bly 30  feet  higher  than  the  railway  station,  or  950  feet  above  tide,  rock 
is  entered  at  8  or  10  feet.  The  public  water  supply  is  reported  by  Manual 
of  American  Waterworks  (1897)  to  be  from  a  drilled  well. 

In  the  south  part  of  the  county,  in  the  vicinity  of  Ideal,  several  wells 
enter  rock  at  30  or  40  foot.  The  loess  in  that  locality  is  about  15  feet  in 
thickness.  At  Argo,  in  Johnson  Creek  Valley,  125  feet  of  sand  and  gravel 
were  penetrated  before  striking'  rock. 

At  Fair  Haven  (altitude  about  875  feet)  the  creamery  well  has  the 
following  section,  furnished  by  the  driller,  Mr.  J.  Schlemming,  of  Chad  wick: 

Section  of  well  at  Fair  Haven,  Carroll  County,  Illinois. 

Feet. 

Drift 40 

Niagara  limestone  and  chert 60 

Mainly  shale 210 

Gray  limestone 15 

Total 325 

Mr.  Schlemming  states  that  the  wells  in  the  south  part  of  Fair  Haven 
Township  often  obtain  water  in  the  cherty  beds  above  the  shale ;  otherwise 
they  must  be  sunk  to  limestone  beds  beneath  the  shale. 

At  Chadwick  the  public  water  supply  is  from  a  well  215  feet  in  depth, 
which  enters  rock  at  59  feet.  The  rock  is  entirely  a  gray  limestone  and 
appears  to  be  the  same  formation  which  was  entered  near  the  bottom  of 
the  Fair  Haven  well.  The  drift  is  mainly  clay,  there  being  "but  little  sand 
or  gravel.  The  head  is  about  40  feet  below  the  level  of  Chadwick  railway 
station,  or  735  feet  above  tide.  The  well  has  a  diameter  of  5|  inches  and 
is  estimated  to  furnish  400  barrels  per  hour. 

In  the  vicinity  of  Milledge^dlle  the  best  wells  are  about  180  feet  in 
depth  and  are  probably  from  Galena  limestone.  The  town  well  has  a 
depth  of  only  80  feet  and  enters  Galena  limestone  at  12  feet.  Many  wells 
obtain  weak  veins  of  water  at  about  30  feet  near  the  top  of  the  limestone. 


614  THE  ILLINOIS  GLACIAL  LOBE. 


WHITESIDE    COUNTY. 
GENERAL   STATEMENT. 


Whiteside  County  borders  the  Mississippi  River  in  the  third  tier  of 
counties'  from  the  north  line '  of  the  State  and  has  an  area  of  700  square 
miles,  with  Morrison  as  its  county  seat.  Rock  River  leads  through  the 
county  from  the  eastern  border  to  the  southwest  comer  and  receives  the 
drainage  of  the  greater  part  of  the  county,  only  a  narrow  belt  on  the  north- 
west being  directly  tributary  to  the  Mississippi.  The  southern  half  of  the 
county  is  a  lowland  tract  standing  but  little  above  the  level  of  Rock  River, 
its  general  elevation  being  about  650  feet  above  tide.  The  northern  and 
western  portions  have  an  altitude  corresponding  with  that  of  the  uplands 
in  Carroll  and  Ogle  counties,  the  altitude  of  a  considerable  part  being 
above  800  feet  and  in  places  reaching  nearly  900  feet.  Two  narrow  low- 
land tracts,  resembling  river  valleys,  connect  the  Mississippi  River  with 
the  lowland  bordering  Rock  River,  one  of  which,  on  the  southwest  border 
of  the  county,  is  known  as  Meredosia  Slough,  and  one,  leading  from  near 
Fulton  to  Fenton,  as  Cattail  Slough  (see  PI.  XVIII).  These  sloughs  stand 
so  little  above  the  level  of  the  Mississippi  and  Rock  rivers  that  they  are 
occupied  in  flood  stages  of  either  stream,  and  the  direction  of  flow  depends 
upon  the  stream  which  chances  to  have  the  higher  stage. 

On  the  uplands  the  drift  is  of  variable  thickness,  but  is  generally 
thinner  in  the  northern  and  northeastern  portions  than  in  the  western  por- 
tion of  the  county.  The  general  thickness,  however,  seldom  falls  below 
50  feet  even  on  ridges.  In  the  western  portion,  from  near  Fulton  south- 
ward past  Garden  Plain  to  Erie,  there  appears  to  be  an  average  thickness 
of  fully  150  feet.  Were  this  drift  removed,  the  elevation  would  differ  but 
little  from  that  of  the  lowland  tracts  bordering  Rock  River,  for  rock  is 
often  found  at  slight  depth  beneath  these  lowlands  except  in  the  southeast 
portion  of  the  county.  In  the  uplands  of  the  northern  portion  of  the 
county  some  wells  are  sunk  to  considerable  depth  in  the  rock.  In  the  west- 
!,  em  portion  they  usually  obtain  water  in  the  drift  or  at  slight  depth  in  the 

j,i  rock.     On  the  lowlands  north  of  Rock  River  the  wells  are  generally  shal- 

ji  low  and  often  enter  the  rock  a  few  feet.     In  the  southeastern  part  of  the 

county  much  of  the  land  has  not  been  brought  under  cultivation,  the  sur- 


WELLS  OF  WHITESIDE  COUNTY,  ILLINOIS.  "  615 

face  being  either  sandy  or  marshy,  and  comparatively  few  deep  wells  have 
been  sunk.  Deep  wells  in  the  neighboring  portions  of  Lee  and  Bureau 
counties  penetrate  over  200  feet  of  drift,  and  it  is  probable  that  a  similar 
depth  extends  over  three  or  four  townships  in  the  southeast  part  of  this 
county. 

INDIVIDUAL    WELLS. 

At  Fulton,  in  the  Mississippi  Valley,  in  the  northwest  comer  of  the 
county,  the  city  water  suppl}^  is  from  an  artesian  well  1,246  feet  in  depth, 
which  terminates  in  the  Potsdam  sandstone.  A  flow  of  sulphurous  water 
was  struck  at  about  475  feet.  Another  flow  was  obtained  from  the  Potsdam 
at  940  to  1,050  feet.  The  head  is  sufficient  to  carry  the  water  60  feet  above 
the  surface,  or  about  655  feet  above  tide.  The  well  has  a  diameter  of  5 
inches  and  an  estimated  capacity  of  300  gallons  per  minute.  The  drift  at 
this  well  is  reported  by  the  engineer  of  waterworks  to  be  125  feet,  but  Prof. 
J.  A.  Udden  obtained  a  record  which  is  thought  to  be  more  reliable  in  which 
the  drift  is  rejDorted  to  be  aboiit  200  feet.  Shallow  wells  in  the  valley  in 
the  vicinity  of  Fulton  are  obtained  at  a  depth  of  about  25  feet.  Wells  on 
an  island-like  upland  in  the  north  part  of  the  city,  standing  100  feet  more 
or  less  above  the  river,  are  sunk  to  depths  of  60  or  75  feet.  They  enter 
rock  at  the  base  of  the  loess  at  about  25  to  30  feet,  thei-e  being  but  little 
glacial  drift. 

Near  Ustick  rock  is  usually  entered  on  ridges  at  about  50  feet  and  in  i 

places  at  much  less  depth,  but  occasionally  a  greater  depth  is  found.     A  ' 

well  on  a  ridge  one-fourth  mile  south  of  Ustick  did  not  reach  rook  at  200 
feet.  Farther  east,  in  the  elevated  part  of  the  county,  wells  enter  rock  at 
50  to  75  feet  and  not  infrequently  reach  depths  of  100  to  150  feet  or  more. 

In  the  vicinity  of  Garden  Plain,  in  T.  21,  R.  3  E.,  wells  enter  a  bed  of  jj 

black  muck  containing  wood  at  a  depth  of  30  or  40  feet.  The  material 
above  the  muck  is  usually  free  from  pebbles  and  is  of  the  coarseness  of  sand 
rather  than  of  loess.  '  There  appears  to  be  no  till  or  other  strictly  glacial 
material  above  the  soil  Beneath  this  muck  a  blue  till  is  entered,  which 
extends  usually  to  the  rock  at  a  level  65  to  100  feet  or  more  below  the  sur- 
face. East  and  south  from  Garden  Plain  the  distance  to  the  blue  till  varies 
from  25  feet  or  less  up  to  about  50  feet.     A  well  in  sec.  24  enters  blue  till 


616  THE  ILLINOIS  GLACIAL  LOBE. 

at  25  feet  and  rock  at  67  feet.     A  well  in  sec.  26  entered  rock  at  78  feet 
without  jjenetrating  any  bine  cla j,  the  following  being  its  section : 

Section  of  a  well  near  Garden  Plain,  Illinois. 

Feet. 

Loess 15 

Fine  sand 15 

Coarse  sand,  becoming  gravelly  near  bottom 48 

Rock 5 

A  well  in  sec.  11,  106  feet  in  depth,  enters  rock  at  about  100  feet.  Pro- 
fessor Udden  reports  that  in  sees.  1  and  2  of  this  township  rock  is  stmck  at 
a  depth  of  only  30  feet. 

In  the  vicinity  of  Union  Grove  and  thence  east  to  Morrison  the  wells 
usually  enter  rock  at  less  than  30  feet,  but  a  well  in  sec.  18,  70  feet  in  depth, 
peueti-ates  rock  only  2  feet.  It  is  entirely  tln-ough  sand,  and  is  reported  to 
have  peneti'ated  snail  shells  near  the  base  of  the  sand.  A  well  near  the 
center  of  sec.  12  enters  rock  at  63  feet,  and  is  reported  to  be  entirely  through 
loess  and  sand,  except  3  feet  of  gravel  at  the  top  of  the  rock  (Udden). 

The  public  water  supply  for  the  city  of  Momson  is  obtained  from 
springs  in  Rock  Creek  Valley.  An  artesian  well  was  sunk  at  this  city  to  a 
depth  of  1,190  feet.  Mr.  S.  D.  Gossert,  editor  of  the  Whiteside  Sentinel, 
reports  that  the  head  is  sufficient  to  carry  the  water  15  feet  above  the  sur- 
face, but  the  well  was  not  in  use  at  the  time  his  communication  was  received 
(August,  1895).  Mr.  Gossert  reports  that  the  wells  in  the  ^dcinity  of  Mor- 
rison range  from  35  to  about  80  feet  in  depth,  and  are  in  nearly  all  cases 
obtained  fi-om  the  rock.  Southeast  of  Morrison,  near  the  south  border  of 
the  township,  the  present  writer  obtained  records  of  several  wells  which  do 
not  enter  rock  at  depths  of  40  or  50  feet,  but  other  wells  in  that  vicinity 
enter  rock  at  about  20  feet. 

Rock  outcrops  extensively  in  the  vicinity  of  Rock  Falls  and  Sterling. 
But  a  well  in  sec.  33  of  this  township  is  repoited  by  Professor  Udden  to 
penetrate  drift  84  feet  and  to  terminate  in  limestone  at  313  feet.  With  the 
exception  of  5  feet  near  the  bottom  of  the  drift,  there  was  no  clay  in  this 
well  section,  the  greater  part  being  sand  and  fine  gravel. 

The  public  water  supply  at  Sterling  and  also  at  Rock  Falls  is  obtained 
fi'om  an  artesian  well  1,450  feet  in  depth,  which  terminates  in  the  Potsdam 
sandstone.^     The  well  ovei-flows  at  an  elevation  about  670  feet  above  tide 

'The  Manual  of  American  Waterworks,  1897,  reports  a  depth  of  1,600  feet. 


WELLS  OF  WHITESIDE  COUNTY,  ILLINOIS. 


617 


and  has  an  estimated  capacity  of  350  gallons  per  minute.  An  analysis  is 
given  in  the  Seventeenth  Annual  Report  of  this  Survey/  which  shows  it  to 
be  a  moderately  hard  water  with  veiy  little  salinity.  Private  wells  in  the 
vicinity  of  Sterling  range  in  depth  from  25  to  100  feet,  with  an  average 
about  35  feet.  Only  the  shallowest  ones  are  obtained  in  gravel,  the 
remainder  being  from  limestone. 

In  the  vicinity  of  Prophetstown  wells  are  usually  obtained  at  less  than 
50  feet  without  entering  rock  and  are  mainly  through  gravel.  A  short  dis- 
tance northwest  from  Prophetstown,  on  the  north  side  of  Rock  River,  rock 
is  found  at  slight  depth  and  it  occasionall}^  outcrops.  But  east  from 
Prophetstown  as  far  as  the  county  limits  (16  miles)  no  records  of  wells 
reaching  rock  were  obtained. 

In  T.  20,  R.  3  E.,  which  is  situated  near  the  western  border  of  the 
county,  the  following  sections  of  deep  wells  were  obtained: 

Wells  in  T.  30,  B.  3  U.,  Whiteside  County,  Illinois. 


Owner  or  location. 

Altitude 
(above  tide). 

Depth. 

Eemark3. 

Feet. 

Feet. 

F.  S.  Huntj  sec.  3 

750 

85 

Loess  and  sand,  20  feet ;  fine  blue  sand,  25  or  30  feet ; 

blue  till,  35  or  40  feet ;  gravel  and  Tvater,  5  feet. 

Chester  E^e,  sec.  4 

740 

163 

Water  from  gravel  at  160-163  feet ;  rock  ( ?)  at  bot- 

tom. 

Sclioolhouse  sec. 4         ... -. 

740 

193 

Loess,  15  or  20  feet ;  blue  sand,  10  or  15  feet ;  blue 

till  (mainly),  160  feet.     Thought  to  have  struck 

rock  at  bottom. 

Mr.  Huegins,  sec.  9.-... - 

740 

160 

Loess,  15  or  20  feet;  blue  sand,  10  or  15  feet;  blue 

till  with  thin  gravel  beds,  120  feet;  white  sand, 

10  feet.     Thought  to  have  struck  rock. 

William  Roland,  sec.  10 

740 

147 

Little  if  any  rock  penetrated. 

S.  Miller,  sec.  21 

625 
690 
630 
680 

65 

150 

78 

70 

Wm.  Miller,  sec.  21 

Limestone  at  bottom. 

Terminates  in  gravel. 

Sec.  33 

Several  wells  70  feet  deep  do  not  enter  rock. 

720 

139 

Rook  at  126  feet. 

In  the  vicinity  of  Erie  wells  reach  a  depth  of  about  40  feet  without 
entering  rock.  The  majority  obtain  water  at  20  or  30  feet.  They  are 
mainly  thi-ough  a  fine  sand.     A  well  in  section  3  of  this  townsliip,  47  feet 


I  Part  II,  p.  828. 


618 


THE  ILLINOIS  GLACIAL  LOBE. 


in  depth,  penetrates  10  feet  of  clay,  below  which  it  is  entirely  in  sand.  A 
well  in  section  22,  altitude  580  feet,  enters  rock  at  about  27  feet  (Udden). 
Professor  Udden  reports  the  follow  ing  sections  of  deep  wells  south  of  Rock 
River  in  the  vicinity  of  Spring  Hill :  ^ 

Wells  near  Spring  Hill,  Illinois. 


Owner  or  locatiou. 

Altitude 
(above  tide). 

Depth. 

Remarks. 

Feet. 

Feet. 

630 

70 

Hervy  StiiU,  sec.  5 

590 

40 

No  rock  struck. 

A.  Colbert,  sec.  20 

660 

117 

Bowlder  clay,  75  feet ;  saud,  42  feet. 

Spring  Hill  post-office 

640 

100 

No  rock  struck. 

B  B  Brooks  sec  29              .  .. 

660 

90 

Loess,  20  feet ;  blue  clay,  60  feet ;  gravel  at  bottom. 
Sand,  16  feet ;  blue  clay,  90  feet ;  sand  with  water, 

Stanley  Fuller,  sec.  29 

660 

130 

18  feet;  rock,  6  feet. 

David.  Uhricli 

660 

100 

Loess  aud  till,  50  feet;  sand,  12  feet:  blue  till   30 

feet ;  sand,  8  feet. 

E.  Crozier,  sec.  32 

650 

100 

Clay,  60  feet;  sand,  40  feet. 

A.  Crozier,  sec.  32 

640 

101 

Yellow  clay,  10  feet;    blue  clay,  30  feet;  sand  at 

bottom. 

Sec.  30,  near  center 

640 

90 

"Hardpan"  at  bottom,  perhaps  shale. 

Mr.  Bryant,  sec.  36 

625 

60 

Entirely  through  sand. 

A  well  driller  at  Prophetstown  informed  the  writer  that  he  had  struck 
rock  in  one  well  near  Spring  Hill  at  90  feet,  and  in  another  at  about  100 
feet.  Probably  the  deepest  well  in  the  vicinity  of  Spring  Hill  is  on  the 
farm  of  Mr.  Hemy  Smead,  in  sec.  SI.  This  reached  a  depth  of  215  feet, 
and  is  thought  by  Mr.  Smead  to  have  terminated  in  a  stony  clay,  apparently 
till.  As  the  well  mouth  is  not  more  than  640  feet  above  tide,  this  section 
indicates  the  presence  of  a  very  deep  preglacial  valley. 

Several  families  in  the  callage  of  Spring  Hill  liave  obtained  a  supply 
of  water  from  a  well  only  20  feet  in  depth,  sunk  on  low  sandy  ground  east 
of  the  village.  A  windmill  forces  the  water  to  a  tank,  from  which  the  water 
is  distributed  thi'ough  pipes  to  the  dwellings.  The  total  expense,  aside  from 
laying  pipes,  is  only  S5  per  annum  for  each  dwelling.  The  water  thus 
obtained  is  but  moderately  hard,  and  is  preferred  to  the  very  hard  water 
obtained  from  the  till  encountered  by  wells  in  the  village.     In  this  conuec- 

'  Coinmiuiic;ited  to  llir  writer. 


WELLS  OF  EOCK  ISLAND  COUNTY,  ILLINOIS.  619 

tion  it  may  be  stated  that  the  wells  throughout  the  sand  district  of  the 
Green  River  Basin  are  re]3orted  to  furnish  a  \vater  that  is  less  hard  than 
.that  obtained  froiii  the  till. 

ROCK  ISLAND   COUNTY. 
GENERAL    STATEMENT. 

Rock  Island  County  occupies  a  narrow  strijj  bordering  the  Mississippi 
River  for  a  distance  of  about  50  miles,  the  city  of  Rock  Island,  its  comity 
seat,  being  about  midway  of  its  western  border.  The  area  of  the  county 
being  but  440  square  miles,  its  average  width  is  less  than  10  miles.  Rock 
River  divides  it  into  two  nearly  equal  portions  and  forms  the  eastern  border 
for  about  20  miles  in  the  northern  part  of  the  county.  Meredosia  Slough 
forms  the  northern  border  of  the  county.  Between  this  slough  and  the  vil- 
lag-e  of  Hampton  there  is  an  island-like  tract  of  upland  standing  about  150 
feet  above  the  Mississippi  River,  which  at  times  of  high  water  either  in  the 
Mississippi  or  Rock  River  is  completely  encircled  by  streams.  Between 
this  u]3land  and  the  city  of  Moline  a  gravel -filled  valley,  called  "Pleasant 
Valley,"  leads  across  from  Rock  River  to  the  Mississippi  (see  PI.  XVIII). 
Its  elevation  is  but  a  few  feet  above  the  high-water  stages  of  the  streams. 
Between  this  valley  and  Rock  River  is  another  island-like  tract  of  upland 
leading  from  the  city  of  Rock  Island  eastward  to  Carbon  Cliff,  which  stands 
about  150  feet  above  the  Mississippi  and  Rock  rivers.  South  from  Rock 
River  Valley  is  an  upland  tract  rising  gradually  southward  from  an  eleva- 
tion of  150  feet  above  the  river  at  the  bluff  to  fully  250  feet  at  the  Mercer 
County  line,  or  to  slightly  more  than  800  feet  above  tide. 

The  island-like  upland  tract  northeast  from  Hampton  has  a  denosit  of 
loess  30  or  40  feet  in  thickness,  beneath  which  there  is  blue  till  extending 
to  the  rock,  which  is  usually  entered  at  100  feet  or  less.  The  upland 
between  the  city  of  Rock  Island  and  Carbon  Cliff  has  about  40  feet  of 
loess  near  the  Mississippi,  but  the  thickness  decreases  eastward  to  scarcely 
more  than  25  feet  at  Carbon  Cliff.  Beneath  this  loess  is  a  thin  sheet  of 
glacial  drift,  rock  usually  being  struck  at  50  to  75  feet.  The  upland  south 
of  Rock  River  has  a  loess  capping  about  25  to  40  feet  in  thickness  on  the 
borders  of  the  Rock  and  Mississijjpi  rivers,  which  decreases  southward  to  15 
feet  or  less  at  the  Mercer  County  line.  On  the  brow  of  the  Rock  and  Mis- 
sissippi River  bluffs  rock  is  usually  entered  in  wells  at  50  to  60  feet,  but  on 


620 


THE  ILLINOIS  GLACIAL  LOBE. 


the  more  elevated  upland  near  the  Mercer  Count}-  line  there  is  nearly  150 
feet  of  drift,  mainly  a  blue  till. 

Tln-oug-hout  the  county  wells  usually  obtain  an  abundance  of  water, 
without  entering  the  rock,  though  those  on  the  upland  are  often  sunk  to 
depths  of  75  or  100  feet.  In  the  valleys  northeast  of  Rock  Island  wells 
are  usually  obtained  at  depths  of  30  or  40  feet  without  entering  rock. 
Along  Rock  River  and  the  portion  of  the  Mississippi  Valley  below  Rock 
Island  the  drift  deposits  are  thin  and  wells  frequently  enter  the  rock. 


INDIVIDUAL    WELLS. 


The  following  well  sections  include  the  deepest  of  which  records  have 
been  obtained  aside  from  the  artesian  wells.  About  one-half  the  sections 
were  collected  for  the  Survey  by  Prof  J.  A  Udden,  who  has  kindly 
furnished  them  for  publication  in  this  place. 

Table  of  irelh  in  Rock  Island  County. 


Owner  or  location. 

Altitude 
(above  tide). 

Depth. 

Eemarks. 

Feet. 

Feet. 

Sec.  9,  T.  19,  E.  2  E 

700 

102 

Loess    30  or  40  feet*  till    60  feet*  limestone    a  few 

feet. 

Cr6aEQ6ry,  sec.  15 -.... 

680 

88 

Loess,  12  feet ;  quicksand,  27  feet ;  black  muck  ■vritli 
wood,  9  feet ;  blue  clay,  40  feet. 

H.  Sadorjs,  sec.  16 

700 

90 

Loess,  30  or  40  feet;  blue  till,  40  feet;   shale   and 

limestone,  a  few  feet. 

W.  McRoberts,  sec.  17 

720 

107 

Loess,  20  feet ;    sand,  64   feet ;   rock  with  i^as,  23 

feet. 

A.  Spaid,  sec.  17 

720 

120 

Loess,  20  feet;  quicksand,  80  feet;  gravel,  8  feet; 
white  shale,  12  feet;  limestone  at  bottom. 

Mrs.  Genung,  sec.  21 

700 

100 

Loess,  30  or  40  feet;  till,  45  or  50  feet;  shale  and 

limestone,  a  few  feet. 

H.McCall,8ec.22 

710 

185 

Loess,  20  feet;  soil  and  wood,  5  feet;  sandy  drift, 
70  feet;  sh.ale  and  limestone,  90  feet. 

L.  Gay  lord,  sec.  31   

670 

65 

Loess,  40  feet;  tine  gravel,  25  foot;   Coal  Measure 

sandstone  <at  bottom. 

H.  C.  Geniing,  sec.  35 

680 

135 

Rock  entered  at  about  100  feet. 

Sec.8,T.  19,R.3E 

575 

40 

In  sand  below  hard  clay. 

A.  Goodrich,  sec.  8 

600 

67 

Rock  entered  at  55  feet. 

Sec.  9,  T.  18,  R.  2  E 

600 

38 

Limestone  at  20  feet. 

Sec.  18,  T.  18,  R.  2  E 

670 

80 

Loess,  30  feet;  sand,  40  feet;  shale,  10  feet;  wood 

in  the  sand. 

WELLS  OF  ROCK  ISLAND  COUNTY,  ILLINOIS. 

Table  of  wells  in  Bock  Island  County — Contined. 


621 


Owner  or  location. 

Altitude 
(above  tide). 

Depth. 

Kemarks. 

Feet. 

Feet. 

See.  12,  T.  18,  R.  1  E 

680 

100 

Loess,    30   feet;    till,   etc.,   70    feet;    sandstone    at 

bottom. 

Bluff  east  of  Hampton.- 

680 

80 

Loess,  30  feet;  till,  blue  near  bottom,  50  feet;  no 
rock  exposed. 

Upland  west  of  Carbon  Cliff.. 

650 

45 

Loess,  25  feet;  till,  15  or  20  feet. 

fjock  Island  near  Tliirty-sixth 

625 

34 

Near  base  of  bluff;  yellow  till,  5  feet;  black  muck, 

street. 

1  foot;  brown  till,  7  feet;  blue  till,  4  feet;  black 
calcareous  fossiliferous  silt,  8  feet;  black  muck, 
4  feet;  green  clay  with  local  pebbles,  5  feet; 
shale  at  bottom. 

Moline,  Seventh  avenue  and 

590 

30 

Loess  beneath  pebbly  clay  at  30  feet. 

Fifth  street. 

Sees.  7  and  12,  T.  17,  Es.  1  and 

680 

65 

Ravines  expose  loess  45  feet ;  black  soil,  2  feet ;  till. 

2W. 

12  feet;  fossiliferous  loess,  6  feet. 

Sec.  17,  T.  16,  E.  2  W 

775 

105 

Loess,  15  feet ;  yellow  till,  15  feet ;  blue  till,  73  feet; 
sandstone,  2  feet. 

Tavlor  Ridge 

796 

82 

At  village  well,  loess,  15  feet;  till,  67  feet;  sand  at 
bottom. 

W.  S.  Parks,  sec.  15    

800 
825 

150 
83 

Rock  struck  at  140  feet. 

W.  H.  Wheaton,  sec.  34 

Mainly  till;  no  rock  struck. 

Illinois  City 

715 

40 

Loess,  20  feet;  black  soil,  3  to  5  feet;  till   15  or  ''0 

feet. 

Sec.  32,  T.  15,  E.  5  W 

725 

130 

Ravines  expose  loess  25  feet;  black  soil,  2  or  3  feet; 
till,  90  feet;  fossiliferous  loess,  12  feet. 

■ 

The  public  water  supply  at  Moline  and  Rock  Island  is  pumped  from 
the  Mississippi  River.  Several  artesian  wells  have  been  sunk  at  these  cities ; 
also  one  at  Carbon  Cliff,  and  one  at  Milan.  Prof.  J.  A.  Udden  has  collected 
a  larg-e  amount  of  data  concerning  the  wells  and  examined  the  drillings 
from  several  of  them.  The  results  of  his  investigations  are  presented  in 
the  Seventeenth  Annual  Report  of  this  Survey.^  The  public  water  supply 
at  Milan  is  from  an  artesian  well,  1,157  feet  in  depth,  which  has  a  head  68 
feet  above  the  surface. 

1  Part  II,  pp.  829-849. 


622  THE  ILLINOIS  GLACIAL  LOBE. 


MERCER  COUNTY. 
GENERAL    STATEMENT. 


Mercer  County  borders  the  Mississippi  River  immediately  south  of 
Rock  Island  County  and  has  an  area  of  655  square  miles,  with  Aledo  as  the 
county  seat.  It  is  drained  by  Edwards  River  and  Pope  Creek,  each  stream 
having  a  westward  course  entirely  across  the  county.  On  the  immediate 
borders  of  the  Mississippi  the  uplands  are  but  675  to  725  feet  above  tide, 
but  there  is  a  gradual  rise  eastward  across  the  county  to  an  altitude  of  over 
800  feet.  Very  few  data  concerning  the  wells  have  been  obtained,  the 
writer  having  made  but  a  single  trip  across  the  county.  The  drift  appears 
to  be  much  thicker  in  the  northern  and  eastern  portions  than  in  the  southern 
and  western  portions.  In  the  latter  district  wells  on  the  uplands  often  enter 
rock  at  50  feet  or  less,  while  in  the  former,  if  we  may  judge  by  wells  in  the 
adjacent  portions  of  Rock  Island  and  Henry  counties,  the  drift  has  a  thick- 
ness of  about  150  feet.  It  is  probable  that  the  filling  along  the  valley  of 
the  Mississippi  in  the  western  jjart  of  this  county  is  at  least  150  feet,  for  the 
river  there  is  following  the  line  of  a  deeply  filled  preglacial  valley. 


INDIVIDUAL    WELLS. 


The  public  water  suppl}''  of  the  city  of  Aledo  is  obtained  from  a  well 
3,115  feet  in  depth,  which  probably  is  exceeded  in  depth  by  but  one  other 
well  within  the  limits  of  the  State,  a  prospect  boring  for  salt  water  at 
St.  Johns  which  at  last  report  (March,  1899)  had  reached  a  depth  of  over 
3,600  feet.  The  Aledo  well  terminates  in  the  Potsdam  sandstone  and  has 
a  head  1&  feet  below  the  surface,  or  about  665  feet  above  tide.  The  Avell 
is  cased  only  240  feet  from  top  and  100  feet  at  1,705  to  1,805  feet.  Water 
was  struck  at  several  levels,  tAvo  strong  veins  being  found  near  the  base  of 
tlie  drift  at  41  and  60  feet  from  the  surface,  and  others  in  the  Galena  and 
St.  Peter  and  lower  strata.  The  water  was  not  markedly  saline  until  a 
depth  of  2,620  feet  had  been  reached.  The  temperature  is  68°  F.  The 
private  wells  in  Aledo  and  vicinity  are  obtained  at  a  depth  of  only  20  feet. 

At  Keithsburg,  in  the  Mississippi  Valley,  tlie  public  water  supply  is 
obtained  from  wells  di'iven  to  a  depth  of  20  or  30  feet  in  tlie  valley  gravel. 

A  well  on  a  terrace  of  Edwards  River,  in  sec.  11,  T.  14,  R.  6  W., 
entered 'a  bed  of  peat  at  a  depth  of  44  feet,  specimens  of  which  were  col- 


WELLS  OF  HENRY  COUNTY,  ILLINOIS.  623 

lected  by  the  writer.  A  well  driller  at  Aledo  states  that  a  peaty  soil  is 
occasionally  struck  in  the  western  part  of  this  county  at  a  Jevel  lower  than 
the  base  of  the  loess,  it  being  in  some  instances  45  feet  below  the  surface. 
This  is  probably  the  Yarmouth  soil  of  pre-Illinoian  age.  A  soil  is  also 
found  at  the  base  of  the  loess,  15  or  20  feet  below  the  surface,  which  is 
evidently  the  Sangamon  soil. 

The  thickest  section  of  drift  reported  within  the  county  is  in  a  well 
one-half  mile  northeast  of  Joy,  where  a  depth  of  70  feet  was  reached  with- 
out entering  rock.  A  ravine  leading'  into  the  Mississippi  Valley  just  north 
of  the  county  line  exposes  130  feet  of  drift,  as  noted  in  the  discussion  of 
Rock  Island  County. 

HENRY  COUNTY. 
GENERAL  STATEMENT. 

Henry  County  is  situated  east  of  Rock  Island  and  Mercer  counties,  and 
has  an  area  of  830  square  miles,  with  Cambridge  as  the  county  seat.  Rock 
River  forms  a  portion  of  its  border  on  the  northwest ;  Grreen  River  traverses 
its  northern  portion  in  a  westward  course,  and  Edwards  River  its  southern 
portion.  The  north  part  of  the  county  from  the  vicinity  of  the  Chicago, 
Rock  Island  and  Pacific  Railroad  northward  is  a  low  sandy  area,  imper- 
fectly drained  by  Green  River.  The  remainder  of  the  county  is  an  upland, 
standing  100  to  200  feet  higher  than  the  sandy  lowland,  a  considerable  por- 
tion being  more  than  800  feet  above  tide.  A  bluff-like  rise  in  part  an 
escarpment  of  sandstone  which  appears  just  south  of  the  line  of  the  Chi- 
cago, Rock  Island  and  Pacific  Railway  is  the  most  conspicuous  topographic 
feature  of  the  county,  though  it  seldom  exceeds  100  feet  in  height,  and 
is  coated  with  drift  to  an  average  depth  of  fully  50  feet. 

The  drift  is  generally  of  moderate  depth,  though  a  few  wells  in  the 
west  part  of  the  county  have  penetrated  150  feet  or  more.  It  is  probable 
that  the  drift  is  heavy  in  much  of  the  low  area  in  the  north  part  of  the 
county  since  it  is  heavy  in  the  adjacent  part  of  Bureau  County;  but  wells 
have  not  been  sunk  in  that  district  to  a  sufficient  depth  to  test  this  question. 

INDIVIDUAL    WELLS. 

The  public  water  supply  at  the  city  of  Greneseo,  in  the  northwest  part 
of  the  county,  is  obtained  from  an  artesian  well  2,250  feet  in  depth,  which 
terminates  in  the  Potsdam  sandstone.     The  well  is  6  inches  in  diameter  and 


624  THE  ILLINOIS  GLACIAL   LOBE. 

has  an  estimated  capacity  of  190  gallons  per  minute.  The  head  is  sufficient 
to  raise  the  water  about  30  feet  above  the  surface,  or  675  feet  above  tide. 
Several  water  veins  were  encountered,  as  follows :  In  the  Devonian  or 
Upper  Silurian  limestone,  at  140  to  160  feet;  Galena,  at  950  to  975  feet; 
Lower  Magnesian,  at  1,350,  1,450,  and  1,590  feet;  Potsdam  sandstone,  at 
2,040  to  2,160  feet.  The  determination  of  the  geological  horizons  was 
made  by  Prof  J.  A.  Udden,  who  also  has  furnished  the  other  data  given. 

The  city  of  Kewanee,  in  the  southeast  part  of  the  county,  also  obtains 
its  public  water  supply  from  artesian  wells,  two  wells  being  1,050  feet  and 
a  third  1,480  feet  in  depth.  The  principal  supply  of  water  in  all  the  wells 
is  probably  from  the  St.  Peter  sandstone  at  a  depth  of  about  1,000  feet,  the 
upper  veins  of  water  being  cased  out.  The  head  is  150  feet  below  the 
surface,  or  700  feet  above  tide,  this  city  being  located  on  an  elevated  tract 
about  850  feet  above  tide.  The  wells  have  a  combined  capacity  of  about 
260  gallons  per  minute.  The  water  is  comparatively  soft  and  of  pleasant 
taste.  Its  temperature  in  each  well  is  65°  Fahr.  The  private  wells  in 
Kewanee  and  vicinity  are  usually  obtained  at  40  or  50  feet  from  gi-avel 
below  till.  The  drift  at  the  artesian  wells  is  about  80  feet  in  depth  and 
mainly  till,  but  at  a  coal  shaft  a  half  mile  east  of  the  city,  at  equally  high 
elevation,  rock  is  entered  at  35  feet. 

At  Galva,  in  the  southern  part  of  the  county,  at  about  the  same  eleva- 
tion as  Kewanee,  rock  is  entered  at  30  to  60  feet,  but  many  of  the  wells 
obtain  an  abundance  of  water  in  the  drift  after  penetrating  a  sheet  of  till. 
The  last  edition  (1897)  of  the  Maimal  of  American  Waterwoi'ks  reports  the 
public  water  supply  to  be  from  a  well.     At  the  brickyards  a  well  has  the 

folk>wing  section: 

Section  in  brichyard  at  Galva. 

Feet. 

Loess 15 

Black  soil  (Sangamon) 1' 

Brown  till  30 

Blue  till 8 

Sandstone  at  bottom. 

The  soil  at  the  base  of  the  loess  is  well  exposed  in  the  clay  pit  at  the 
brickyards.  A  large  log  was  found  embedded  in  this  soil,  but  no  speci- 
mens were  at  hand  at  the  time  of  the  writer's  visit  to  the  locality. 

At  Cambridge  wells  are  usually  obtained  at  a.bout  40  feet,  in  gravel 
beds  below  till.  Occasionally  a  well  reaches  a  depth  of  75  feet.  The  drift 
in  that  vicinity  is  about  60  feet  in  dejith,  including  15  or  20  feet  of  loess. 


WELLS  OF  HEiilRY  COUNTY.  ILLINOIS. 


625 


The  Manual  of  American  Waterworks  reports  the  public  water  supply  to 

be  from  a  deep  well. 

At  Andover,  about  5  miles  southwest  of  Cambridg-e,  a  well  penetrates 

155  feet  of  drift,  striking  rock  near  the  bottom.     The  lower  20  feet  of  the 

drift  is  sand,  the  remainder  mainly  till. 

At  Lynn  Center  and  vicinity  several  wells  enter  rock  at  about  115  feet. 

The  section  usually  penetrated  is  as  follows: 


Generalized  section  of  -wells  near  Lynn  Center. 


Feet. 
..   15 


Loess 

Yellow  till 10  or  15 

Blue  till,  -svith  thin  beds  of  sand 80 

At  Alpha  wells  are  usually  obtained  at  15  to  30  feet  from  a  gravelly 
drift  at  the  base  of  the  loess  or  near  the  top  of  the  till,  though  a  few  are 
sunk  into  the  rock.  A  well  at  Bolton's  sorghum  mill  enters  rock  at  75  feet, 
and  several  wells  southwest  of  Alpha  reach  rock  at  about  70  feet.  The 
drift  is  mainly  blue  till. 

In  the  vicinity  of  Orion  several  deep  wells  have  been  made  which 
show  the  drift  to  exceed  100  feet.  In  one  instance  rock  was  struck  at  150 
feet.  A  well  at  the  creamery,  130  feet  in  depth,  did  not  reach  rock,  water 
being  obtained  from  sand  beneath  blue  till. 

At  Annawan,  in  the  east  part  of  the  county,  a  well  at  the  creamery, 
223  feet  in  depth,  entered  rock  at  IM  feet.  The  di-ift  is  entirely  clay 
(Udden). 

The  following  sections  of  farm  wells  are  reported  by  Professor  Udden: 

Wells  in  Henry  County,  Illinois. 


Owner  and  location. 

Altitude 
{above  tidei. 

Depth. 

Kemarka. 

Feet. 

Feet. 

Adam  Butzer,  sec.  1,  T.  18,  R.  3  E 

650 

85 

Strikes  rook  at  bottom ;  mainly  through 
sand. 

John  Crozler,  sec.  7,  T.  18,  R.  4  E 

630 

65 

No  rock  struck;  upper  30  feet  sand,  re- 

mainder bowlder  clay. 

William  Arnett,  sec.  6,  T.  18,  E.  4  E 

630 

75 

Upper  40  feet  clay,  remainder  sand. 

Henry  Arnett,  sec.  5,  T.  18.  R.  4  E 

645 

120 

No  rock  struck. 

A  S  Tiifanv  sec  5  T  16  R  4  E 

610 

48 

Terminated  in  gravel. 

In  the  northwest  part  of  T.  15.  R.  4  E.,  at  an  altitude  of  775  feet,  several  wells  60  feet  in  depth 
do  not  reach  the  rock. 

MON  XXXVIII 40 


626  THE  ILLINOIS  GLACIAL  LOBE. 


BUREAU  COUNTY. 
GENERAL  STATEMENT. 


Bureau  County  is  situated  east  of  Henry,  in  the  north-central  part  of 
the  State,  its  southeast  border  being  at  the  Ilhnois  River,  near  the  gi-eat 
bend.  It  has  an  area  of  870  square  miles,  and  Princeton  is  the  county 
seat.  The  nortliwest  part  of  the  count}"  is  a  marshy  and  sandy  district, 
drained  westward  by  Green  River;  the  central  and  northeastern  portions  of 
the  county  are  drained  by  Bureau  Creek,  a  tributary  of  the  Illinois;  the 
southwestern  portion,  which  is  an  elevated  district,  divides  its  waters 
between  Grreen  River  on  the  north  and  Spoon  River  on  the  south. 

The  bulky  morainic  system  forming  the  outer  border  of  the  Wisconsin 
drift  passes  southward  through  the  central  portion  of  this  county,  leaving 
a  belt  10  or  12  miles  in  average  width  on  the  west  Ijorder  of  the  county, 
which  is  outside  the  limits  of  the  Wisconsin  drift.  This  morainic  system 
constitutes  the  highest  portion  of  the  county,  much  of  its  main  crest  being 
above  900  feet.  Yet  it  apparently  crosses  and  occupies  for  a  few  miles  the 
deep  preglacial  valley  through  which  Rock  River  is  supposed  to  have  dis- 
charged to  the  Illinois.  The  moraine  is  so  bulky  as  to  completely  conceal 
the  course  of  this  valley,  whose  presence  is  known  only  by  well  boring-s. 
It  is  probable  that  the  drift  in  places  exceeds  600  feet  in  depth  where  the 
moraine  occupies  this  old  valley.  The  sections'  given  below  will  set  forth 
the  basis  for  this  opinion. 

With  the  exception  of  a  narrow  strip  on  the  southern  border  of  the 
county,  and  the  elevated  southwestern  portion  outside  the  Wisconsin  drift 
sheet,  the  drift  of  this  county  is  a  very  heavy  deposit.  The  avferage  of  29 
well  sections  which  reach  rock,  the  majority  of  which  are  in  the  southwest 
part,  show  a  thickness  of  155  feet;  but  this  is  evidently  much  below  the 
average  for  the  county,  since  82  records  of  deep  wells  whicli  do  not  reach 
rock  and  wliich  are  scattered  widely  over  the  county  are  found  to  average 
190  feet  in  de})th.  It  is  probable  that  the  average  thickness  for  the  county 
exceeds  200  feet,  and  it  may  ])0ssibly  reach  300  feet.  It  is  thought  that 
the  thickness  is  greater  in  this  county  than  in  any  other  within  the  State. 

The  upper  portion  of  the  drift,  to  a  depth  of  100  feet  or  more,  in  the 
portion  of  the  county  covered  l)y  the  Wisconsin  slieet  is  composed  in  the 
main  of  a  blue  till.     The  well  sections  indicate  that  the  lower  portion  of 


WELLS  OF  BUREAU  COUNTY,  ILLINOIS.  627 

the  drift  contains  a  larger  proportion  of  sand  and  g-ravel  than  the  upper.  In 
the  marshy  area  outside  the  Wisconsin  sheet,  which  occupies  much  of  the 
northwest  part  of  the  county,  there  is  a  surface  sand  a  few  feet  in  depth, 
but  the  deep  wells  usually  penetrate  a  large  amount  of  clay.  Sand  dunes 
also  cover  portions  of  the  elevated  moraine.  In  the  southwestern  portion 
of  the  county  the  drift  is  of  variable  constitution  and  contains  but  a  small 
amount  of  blue  till,  except  where  its  depth  is  unusually  great. 

In  the  eastern  portion  of  the  county  numerous  instances  of  the  occur- 
rence of  a  buried  soil  have  been  brought  to  light  by  the  deep  wells.  In 
several  of  the  wells  which  penetrate  a  buried  soil  inflammable  gas  has  been 
obtained,  which  in  some  instances  has  been  of  sufficient  strength  to  furnish 
light  and  fuel  for  dwellings  for  a  period  of  several  years.  Three  wells  in 
the  village  of  Lamoille  show  gas  with  a  pressure  of  18  pounds  per  square 
inch,  another  20  pounds,  and  still  another  about  11^  pounds.  A  dozen  or 
more  other  wells  have  a  weaker  pressure.  A  well  at  George  Windle's,  2 
miles  east  of  Lamoille,  has  a  pressure  of  26  pounds  per  square  inch,  and 
one  at  C.  L.  Dayton's,  3  miles  north  of  Lamoille,  has  a  pressure  of  28 
pounds.  Many  other  weaker  wells  are  found  between  Lamoille  and  Men- 
dota.  The  strong  wells  usually  obtain  gas  in  sand  and  gravel  wliile  the 
weak  ones  find  it  in  a  greenish  clay,  associated  with  the  buried  muck  and 
soil.  It  seems  probable  that  the  gas  is  formed  from  the  vegetation  in  these 
muck  beds,  though  another  possible  source  is  found  in  the  escape  upward 
from  the  underlying  Trenton  limestone.  This  limestone  in  the  neighboring 
States  of  Indiana  and  Ohio  is  found  to  yield  gas  in  large  quantities.  The 
heavy  blanket  of  bowlder  clay  which  occurs  in  this  region  forms  a  suitable 
barrier  to  prevent  the  gas  from  escaping.  A  small  amount  of  gas,  how- 
ever, has  been  noted  from  the  early  days  of  settlement  to  escape  along  the 
borders  of  Pike  Creek  in  the  vicinity  of  Lamoille.^ 

INDIVIDUAL   WELLS. 

The  public  water  supply  at  Princeton  is  obtained  from  two  wells, 
2,093  and  2,525  feet  in  depth.  They  apparently  each  terminate  in  the 
Lower  Magnesian  limestone.  The  head  is  about  72  feet  below  the  surface, 
or  638  feet  above  tide.     The  shallower  one  is  cased  to  a  depth  of  1,000  feet, 

'  Tlie  statistics  concerning  these  gas  vrells  were  largely  contributed  by  Miss  Ella  Lemmon,  of  the 
Lamoille  public  schools,  and  by  Mr.  George  Dean,  of  Lamoille. 


628  THE  ILLINOIS  GLACIAL  LOBE. 

with  inner  casing  4|  inches  in  diameter,  and  has  a  capacity  of  320  gallons 
per  minute.  The  water  is  moderately  hard  and  but  slightly  saline.  A  par- 
tial analysis  shows  only  3.7  grains  per  gallon  of  sodium  chloride  and  28.5 
grains  of  total  solids.  A  portion  of  the  water  is  from  the  St.  Peter  sand- 
stone at  a  depth  of  1,520  to  1,670  feet,  and  a  portion  from  the  Lower 
Magnesian  at  1,850  to  1,975  feet.  The  "temperature  of  the  water  is  64°  F. 
These  wells  are  of  exceptional  interest  since  they  strike  into  a  deep  part  of 
the  preglacial  valley  which,  as  indicated  above,  appears  to  have  been  the 
old  coiu'se  of  Rock  River  into  the  Illinois.  A  careful  record  was  kept 
of  the  shallower  well,  and  the  following  section  of  drift  is  reported  by 
Mr.  Jacob  Miller,  of  Princeton : 

Section  of  drift  penetrated  in  a  deep  ivell  at  Princeton. 

Feet. 

Clay 47 

Sand  and  gravel 10 

Bowlder  clay 88 

Gravel  with  Inflammable  gas 5 

Bowlder  clay 25 

Sand  and  gravel 197 

Beneath  the  drift  75  feet  of  shale  was  penetrated  before  hard  rock  was 
entered.  The  deeper  well,  which  was  sunk  several  years  earlier,  is  thought 
to  have  reached  a  depth  of  440  feet  before  entering  rock,  or  about  the  level 
of  the  bottom  of  this  shale.  Mr.  Miller  states  that  its  section  was  not  so 
carefully  kept  as  that  of  the  later  well,  and  it  is  possible  that  the  drift 
was  no  deeper  than  372  feet.  This  gives  the  rock  floor  of  the  valley  an 
altitude  338  feet  above  tide,  or  but  50  feet  liigher  than  low  water  of  the 
Mississippi  at  Cairo,  350  miles  nearer  the  seaboard.  A  well  sunk  at  Prince- 
ton many  years  ago,  and  reported  by  Judge  Shaw  in  the  Geology  of  Illi- 
nois, penetrated  only  216  feet  of  diift  and  was  drilled  to  a  depth  of  but  313 
feet.^  This  well  is  scarcely  one-half  mile  distant  from  the  Avells  just  dis- 
cussed, yet  it  seems  to  ha^'e  struck  the  old  bluff'. 

The  village  of  Buda  obtains  its  public  water  supply  from  a  well  1,610 
feet  in  depth.  The  lower  140  feet  is  thought  by  citizens  to  be  in  St.  Peter 
sandstone.  The  head  is  125  feet  below  the  surface  or  about  640  feet  above 
tide.  The  well  has  a  diameter  of  6  inches  and  will  supply  fully  100  gallons 
per  minute,  as  was  shown  by  a  24-hour  test.  A  strong  water  vein  was 
struck  at  295  feet,  but  this  is  cased  out.    The  casing  extends  into  limestone 

'  Geology  of  Illinois,  Vol.  V,  1873,  pp.  172-173. 


WELLS  OF  BUREAU  COUNTY,  ILLmOIS.  629 

only  a  few  feet  at  a  deptli  of  475  feet.  The  drift  is  mainly  blue  till  and  is 
160  feet  in  depth.  From  the  base  of  the  diift  to  415  feet  there  is  shale  and 
thin  beds  of  sandstone.  A  bed  of  coal  4  feet  thick  was  passed  through  at 
about  225  feet.  The  well  was  mainl}^  in  limestone  from  415  feet  to  1,470 
feet,  where  it  is  thoug'ht  that  St.  Peter  sandstone  was  entered.^ 

An  artesian  well  has  been  sunk  at  Bureau  Junction,  in  the  Illinois 
Valley,  to  a  depth  of  308  feet.  A  flow  of  water  was  obtained  without 
reaching  the  bottom  of  the  Coal  Measures.  The  well  mouth  is  but  475 
feet  above  tide,  and  as  135  feet  of  di-ift  was  penetrated,  the  rock  floor  has 
an  altitude  only  340  feet  above  tide,  or  about  the  same  as  at  Princeton.  A 
neighboring  well  on  the  farm  of  Mr.  Miller,  in  sec.  30,  T.  15,  R.  10  E., 
enters  rock  at  about  the  same  level  above  tide. 

The  deepest  reliable  section  of  drift  reported  within  the  county  is  that 
of  a  well  at  the  village  of  Ohio,  situated  near  the  crest  of  the  moraine  in 
the  northern  part  of  the  county.  This  well  entered  rock  at  a  depth  of  412 
feet,  but  as  the  altitude  is  920  feet  above  tide,  the  rock  floor  is  608  feet,  or 
170  feet  higher  than  in  the  Princeton  well.  It  is  probable,  therefore,  that 
the  well  strikes  the  blufi"  of  the  old  valley. 

At  Neponset,  which  is  situated  on  the  upland  outside  the  Wisconsin 
drift  sheet,  in  the  southwest  part  of  the  county,  the  following  complex 
series  of  drift  deposits  was  penetrated  by  a  coal  shaft: 

Section  of  drift  beds  penetrated  in  a  coal  shaft  at  Neponset. 

Feet. 

Loess 12 

Sand 4 

Blue  clay  (lowan  till  ?) 10 

Peat,  with  wood  enibedded 3 

Marl  of  dark  color 2 

Blue  clay 8 

Sand 3 

Till 18 

Sand 3 

Yellow  till 67 

Total  drift 130 

The  altitude  at  this  shaft  is  about  825  feet  above  tide.  The  position 
of  the  peat  and  marl  beds  in  the  Pleistocene  series  is  not  yet  determined, 
nor  is  it  known  whether  it  is  of  similar  age  to  the  buried  soil  found  within 
the  limits  of  the  Wisconsin  di-ift  in  this  county. 

'  Information  furnished  by  Mr.  A.  J.  Fisher,  of  Buda. 


630 


THE  ILLIISrOIS  GLACIAL  LOBE. 


In  the  following  list  of  deep  wells  the  majority  of  sections  were  col- 
lected for  the  Survey  by  Prof.  J.  A.  Udden,  who  has  furnished  them  for 
publication  in  this  place.  It  should  be  noted  that  where  he  uses  the  word 
"  clay"  there  is  usually  till,  but  such  is  not  always  the  case. 

Table  of  deep  wells  in  Bureau  County. 


Owner  or  location. 

Altitude 
{above  tide). 

Depth. 

Eemarks. 

Feet. 

Feet. 

In  T.  18,  R.  7  E.,  at  New  Bed- 

660 

145 

Water  from  sand  at  bottom ;  drift  mainly  blue  clay. 

ford  School. 

In  sec.  34,  T.  18,  R.  7  E 

670 

136 

Clay,  100  feet ;  sand,  36  feet. 

W.  Meek,  sec.  9,  T.  18,  R.  7  E. .. 

650 

110 

Mainly  blue  clay;  no  rock. 

Oscar  Wolf,  sec.  10,  T.  18,  R.  7E 

680 

200 

Clay,  with  sand  at  bottom. 

A.  J.  AViggins,  sec.  36,  T.  18, 

.800 

270 

Clay,  130  feet;  coarse  gravel,  120  feet;  dry  sand,  60 

R.  7E. 

feet;  bowlder  clay  and  sand,  60  feet;  no  rock. 

Mr.  Erickson,   sec.  36,   T.  18, 

675 

100 

Sand,  10  feet;  clay,  30  feet. 

R.  7E. 

In  T.  18,  R.  8  E.,  at  Bunker 

835 

330 

Sand,  40  feet;  clay,  140  feet;  sand,  2  feet;  clay,  1?3 

HiU  School. 

feet;  sand,  15  feet;  gas  at  210  feet. 

W.  S.  Odell,  sec.  5,  T.  18,  E.  8  E . 

680 

170 

Sand,  20  feet;  clay,  145  feet ;  sand  at  bottom,  5  feet. 

W.  C.  Stearns,  sec.   9,  T.  18, 

750 

303 

Bowlders  in  upper  50  feet;  clay  to  200  feet;  sand. 

R.  8E. 

a  few  feet:  clay  at  bottom. 

Near  Walnut,  in  sec.  9,  T.  18, 

780 

260 

Yellow  till,  13  feet;  sand,  3  feet;  till,  60  feet;  blue 

R.  8  E. 

till,  20  feet;  sand,  2  feet;  hard  till,  15  feet ;  sand, 
1  foot;  blue  till,  141  feet;  sand,  5  feet;  no  rock 
struck. 

Mr.  Waterhouse,  sec.  15,  T.  18, 

815 

280 

Sand  and  clay,  165  feet;  gravel,  5  feet;  clay,  100 

R.8E. 

feet.     Sand  at  bottom.     Gas  at  190  feet. 

Mr.  Rumberger,  sec.  30,  T.  18, 

810 

317 

Sand,  100  feet;  then  clay  to  bottom. 

R.8E. 

Mr.  Milliken,  sec.  35,  T.  18, 

830 

195 

Sand,  40  feet;  gravel,  5  feet;  remainder,  clay. 

R.8E. 

Mr.  Catterman,  sec.  36,  T.  18, 

800 

260 

Clay,  250  feet ;  sand  at  bottom. 

R.8E. 

Walnut  Cheese  Factory 

710 

200 

Blue  clay,  60  feet ;  sand,  10  feet ;  reddish  clay,  80 
feet;  gravel,  3  feet;  fine  sand  at  bottom. 

Ohio,  village  well 

920 

412 

Clay,  150  feet;  sand  with  gas,  50  feet;  clay,  40 
feet;   sandy  blue  bowlder  clay  to  limestone    at 

bottom. 

J.  Jodor,  ne.ar  Ohio,  in  sec.  8.. 

890 

390 

Not  certain  to  have  struck  rock. 

G.WiiiiU«,seu.21,T.  18,  R.  HE. 

800 

242 

Sand,  6  feet;  reddish  clay,  51  feet;  sand,  14  feet; 
reddish  clay,  18  feet;  gravel  with  gas,  14  feet; 
peaty  soil  with  timber,  18  I'eet;  sand,  8  feet; 
gravel  at  bottom,  17  feet. 

WELLS  OF  BUREAU  COUISTY,  ILLINOIS. 

Table  of  deep  wells  in  Bureau  County — Continued. 


631 


Owner  of  locatioD. 

Altitude 
(above  tide). 

Depth'. 

Kemarks. 

Feet. 

Feet. 

W.  Morris,  sec.  31.T.  18,  R.ll  E . 

780 

265 

Clay,  100  feet;  dry  sand,  12  feet;  clay,  40  feet; 
cemented  gravel,  103  feet  (possibly  hard  till). 

W.  Thomas,  sec.  5,  T.  17,  R.  6  E. 

640 

98 

No  rock  struck. 

Robert  Smith,  sec.  16,  T.  17, 

630 

108 

Sand,  40  feet ;  blue  clay,  60  feet ;  sand  at  bottom. 

R.6E. 

G.  Pittmans,  sec.  2,  T.  17,  R.  7E. 

690 

200 

No  rock  struck. 

Mr.  McKnen,  sec.  3,  T.  17,R.7E. 

720 

180 

Mainly  clay ;  no  rock. 

Mr.   McKueD,   sec.  10,  T.  17, 

710 

208 

Mainly  clay;  no  rock. 

E.7E. 

Mr.  Siebel,  sec.  8,  T.  17,  R.  7  E . . 

690 

160 

No  rock  struck. 

Mr.  White,  sec.  13,  T.  17,  R.  7  E . 

750 

220 

No  rock ;  mainly  bowlder  clay. 

H.  Sayers,  sec.  14,  T.  17,  R.  7E. . 

750 

250 

No  rock  struck. 

L.  Miller,  sec.  15,  T.  17,  R.  7  E  . . 

680 

200 

No  rock  struck. 

D.  A.  Miller,  sec.  15,T.  17,R.7E. 

710 

250 

No  rock  struck. 

J.  P.  Follet,  sec.  16,  T.  17,E.7E. 

710 

250 

Clay,  230  feet;  sand  at  bottom ;  wood  at  60  feet. 

W.  J.  McKey,  sec.  18,  T.  17, 

675 

140 

Bowldery  till;  no  rock. 

R.7E. 

D.  Weinck,  sec.  18,  T.  17,  R.  7E. 

675 

140 

Sand,  20  feet;  blue  clay,  100  feet;  fine  blue  sand 
at  bottom. 

A.  Xelson,  sec.  21,  T.  17,  R.  7E. . 

670 

217 

No  rock ;  clay,  180  feet. 

O.  Smith,  sec.  22,  T.  17,  R.  7  E  . . 

750 

272 

No  rock  struck. 

C.  Samuelson,  sec.  24,  T.  17, 

810 

323 

Sand,  20  feet;  clay,  125  feet;  "hardpan,"  130  feet; 

R.7E. 

clay  and  sand  to  bottom,  148  feet. 

C.  Beachler,  sec.  9,  T.  17,  R. 

810 

270 

Clay,  125  feet;  sand  and  gravel  with  "  black  stuff" 

8E. 

embedded,  145  feet. 

P.  Erisman,  sec.  10,  T.17,  R.8  E. 

750 

288 

No  rock  struck. 

J.  Carr,  sec.  11.  T.  17,  R.  8  E . . . . 

750 

265 

Mainly  clay;  no  rock. 

Mr.  Kuaus,  sec.  13,  T.  17,  R.  8  E. 

700 

317 

No  rock  struck. 

J.  Springer,  sec. 25,  T.17,  R.8  E. 

700 

200 

No  rock  ;  wood  in  clay  at  160  feet. 

J.  Gillam,  sec.  6,  T.  17,  R.  9  E . . . 

750 

210 

No  rock  struck. 

E.  Beatty,  sec.  7,  T.  17,  R.  9  E  . . 

725 

200 

Clay,  120  feet;  gravel  with  gas,  20  feet;  clay,  60 
feet.     Sand  at  bottom. 

Mr.  Taylor,  sec.  13,  T.17,  R.9  E. 

740 

165 

Clay,  160  feet.    Sand  with  gas  at  bottom. 

S.  Clark,  sec.  24,  T.  17,  H.  9  E.. . 

720 

277 

Clay,  100  feet;  gravel  with  gas,  17  feet;  clay,  40 
feet;  bowlder  clay,  13  feet;  gummy  clay,  35  feet; 
sandy  hardpan  to  bottom,  70  feet. 

A.  Dunbar,  sec.  26,  T.  17,  R.  9  E . 

730 

180 

Clay,  160  feet.     Black  sand  at  bottom. 

J.  Allen,  sec.  35,  T.  17,  R.  9  E  .. . 

720 

145 

Gas  in  clay  at  bottom. 

J.  Henzell,  sec.  30,  T.17,  R.IOE. 

720 

175 

In  Coal  Measures  rock,  20  feet,  at  bottom. 

Lamoille  Shoe  Factory 

800 

118 

Gas  in  dry  sand  at  bottom. 

Lamoille  Mills 

800 
800 

118 
130 

Gas  in  dry  sand  at  bottom. 
Gas  in  dry  sand  at  bottom. 

Mrs.  Booth,  in  Lamoille 

632 


THE  ILLIlSrOIS  GLACIAL  LOBE. 

Table  of  deep  wells  in  Bureau  County — Continued. 


Owner  or  location. 


Altitude 
(above  tide) 


Depth. 


Kemarke. 


E.  SteTenson.  iu  Lamoille 

L.  Hopps,  near  Lamoille 

C.  L.  Dayton,  near  Lamoille  .. . 
Mr.  Perkins,  sec.  5,  T.17,  E.ll  E 

A.  Searle,  see.  32,  T.  16,  E.  10  E  . 

M.  Frey,  sec.  22,  T.  16,  E.  10  E  .. 

One-half  mile  north  of  Depue. 

K".  Anderson,  sec.  30 

Mr.  Seaton,  sec.  9 

Seaton  and  Ticinity 

Near  Hollo  way  ville 

Ladd,  coal  boring 

Princeton  artesian  well 

Princeton,  old  artesian  well 

Mr.  Eickmeyer,  3  miles  north- 
east of  Princeton. 

A.  T.  AVeise,  sec.36,  T.16,  E.9  E . 

Sec.  20,  T.  16,  E.  9  E 

In  T.  16,  E.  8  E.,  at  Mr.  Kauf- 
mann's,  sec.  13. 

Company's  TveU,  sec.  16,  T.  16, 
E.8  E. 

J.  Sapp,  sec.  18,  T.  16,  E.  8  E..  .. 

L.  L.  Lay,  sec.  31,  T.  16,  E.  8  E . . 

J.  Pottorf,  sec.  32,  T.  16,  E.  8  E  . 

S.  W.  i  sec.  32,  T.  16,  R.  8  E  . . . . 

C.  Hays,  at  Wyanet 


Wyanet  prospect  boring . 
Lovejoy  coal  shaft 


County  farm,  east  of  Wyanet.. 
J.  B.  Stewart,  near  Wyanet  . .. 
Buda,  village  well 


Mrs.  Mammon,  in  Hnda 

E.  Harbrook,  sec.  8,T.  16,  E.  7E 
Nels  Olson,  sec.  12,  T.  16,  E.  7E. 

ShefSeld  and  vicinity 

Mineral,  railway  well 


800 
800 
800 
750 


600 


Feet. 
150 
130 
207 
147 


650 

265 

680 

120 

490 

50 

520 

300 

700 

100 

625 

45 

700 

80 

656 

175 

700 

372 

700 

313 

670 

272 

485 

395 

700 

260 

690 

260 

120 


645 

172 

770 

130 

720 

287 

700 

80 

660 

140 

660 

112 

700 

62 

600 

160 

700 

150 

760 

120 

780 

232 

670 

150 

750 

220 

675 

10 

638 

60 

Gas  well;  uo  rock. 

Gas  jn  sand  at  bottom. 

Gas  and  water  in  sand  at  bottom. 

Yellow  till,  14  feet;  blue  till,  117  feet;   hard  gray 

till,  15  feet.     Sand  with  gas  at  bottom. 
No  rock  struck ;  mainly  sand. 
No  rock;  mainly  sand. 
Entirely  sand. 

Enters  rock  at  about  100  feet. 
Enters  rock  near  bottom. 
Drift,  about  45  or  50  feet. 
Mainly  till :  sand  at  bottom. 
Rock  entered  at  175  feet. 
Bock  entered  at  372  feet. 
Eock  entered  at  216  feet. 
Clay,  90  feet ;  gravel  and  sand,  182  feet. 

Eock  entered  at  160  feet. 

No  rock  struck. 

Clay,  125  feet.     Sand  and  clay  to  bottom. 

Sand,  40  feet ;  blue  till,  80  feet.     Sand  at  bottom. 

No  rock.     Gas  iu  sand  at  85  feet. 

No  rock.     Gas  in  old  soil. 

Eockf  at  bottom. 

Sandstone  entered  at  80  feet. 

Clay,  40  feet ;  sand,  10  feet ;  blue  clay,  25  feet;  clay 

with  sand  veins  to  bottom,  50  feet. 
Eock  entered  at  112  feet. 
Yellow  till,  20  feet;  sand,  12  feet;  blue  till,  30  feet. 

Sandstone  above  coal. 
Not  certain  whether  rock  was  struck. 
Mainly  till.     Wood  and  sand  at  bottom. 
Till,  70  feet;  sand,  10  feet.     Till  with  thin  sand  beds 

to  bottom.     Artesian  well  recently  sunk  has  160 

feet  of  drift. 
Till, 85  feet.     Eemainder  mainly  sand. 
Clay,  75  feet.     Fine  blue  sand  to  bottom. 
Mainly  clay;  lower  50  feet  sand. 
Eock  entered  at  10  to  20  feet. 
In  blue  olav  at  bottom. 


WELLS  OF  PUTNAM  COUNTY,  ILLINOIS. 

Table  of  deep  loells  in  Bureau  County — Continued. 


633 


Owner  or  location. 

Altitude 
(above  tide). 

Depth. 

Kemarks. 

Feet. 

Feet. 

A.  Stevens,  sec.  1,  T.  15,  E.  7  E . . 

750 

200 

Enters  rock  at  150  feet. 

D.  Brady,  sec.  23,  T.  15,  E.  7  E . . 

800 

200 

Enters  rock  at  150  feet. 

In  T.  15,  R.  8  E.,  at  G.  Kitter- 

540 

90 

Entirely  sand. 

man's,  sec.  1. 

Frank  Stevens,  sec.  14,  T.  15, 

720 

116 

Enters  rock  at  116  feet. 

E.8E. 

Mr. Whiting,  sec.l4,T.  15,  E.8E 

700 

100 

Enters  rock  at  100  feet. 

A,  Greenman,  sec.  20,  T.  15, 

650 

212 

Blue  clay,  110  feet;  sand,  102  feet. 

R.9E. 

H.  Benson,  sec.  21,  T.  15,  R.  9  E. 

640 

SCO 

Clay,  120  feet.     Remainder  sand. 

Bureau  Junction 

475 

308 

Drift  135  feet 

S.  Russell,  sec.  5,  T.  15,  E.  10  E  . 

600 

196 

No  rock  struck. 

C.  Averill,  sec.  7,  T.  15,  E.  10  E  . 

500 

130 

Entirely  sand. 

J.  Eudberg,  sec.  8,  T.  15,  E.  10  E 

600 

245 

No  rock ;  mainly  sand. 

Mr.  Miller,  sec.  30,  T.  15,  R.  lOE 

445 

260 

Drift  about  100  feet. 

PUTNAM   COUNTY. 


GENERAL   STATEMENT. 

Putnam  County  is  situated  southeast  of  Biireau,  immediatelj  soutli  of 
the  great  bend  of  the  Illinois,  and  is  traversed  in  a  southward  course  by  that 
stream.  It  is  one  of  the  smallest  counties  in  the  State,  its  area  being  but 
170  square  miles,  and  Hennepin  is  its  county  seat.  The  county  is  situated 
mainly  east  of  the  Illinois  River,  there  being  scarcely  60  square  miles  on 
the  west  side  of  the  stream.  The  valley  of  the  Illinois  River  in  this  county 
has  a  width  of  about  5  miles.  The  remainder  of  the  county  is  an  upland 
standing  200  to  300  feet  above  the  level  of  the  river.  The  most  elevated 
part  is  on  the  eastern  border  near  Mount  Palatine,  where  an  altitude  of  725 
to  750  feet  is  attained. 

Throughout  the  county  there  is  a  heavy  deposit  of  di'ift,  averaging 
fully  150  feet  in  thickness.  The  upper  portion  on  the  uplands  to  a  depth  of 
75  or  100  feet  is  mainly  bowlder  clay,  but  the  lower  portion,  and  nearly  all 
the  di-ift  in  the  valley  of  the  Illinois,  is  sand  and  gravel.  The  list  of  deejj 
wells  presented  below  was  furnished  by  Prof  J.  A.  Udden,  with  the  exception 
of  the  artesian  well  at  Hennepin,  data  concerning  which  were  furnished  by 
A.  T.  Purviance,  county  clerk. 


634 


THE  ILLINOIS  GLACIAL  LOBE. 


INDIVIDUAL   WELLS. 


The  Hennepin  artesian  well  is  800  feet  in  depth  and  has  a  head  sufficient 
to  cany  the  water  at  least  50  feet  above  the  surface.  It  has  a  discharge  of 
80  gallons  per  minute  from  a  4-inch  pipe.  There  is  a  slight  salinity,  but 
the  water  is  not  unpleasant  to  the  taste.  The  well  is  cased  nearly  to  the 
bottom  and  the  water  has  a  temperature  of  58°  F.  The  drift  is  about  150 
feet  in  thickness.  The  altitude  of  the  well  being  scarcely  500  feet,  the 
rock  floor  is  but  350  feet  above  tide,  or  nearly  as  low  as  at  the  wells  in 
Princeton  and  Bureau  Junction. 

The  Putnam  City  artesian  well  obtains  water  from  the  Coal  Measures, 
but  the  depth  was  not  ascertained.  It  penetrated  about  200  feet  of  drift, 
and  entered  rock  at  a  level  slightly  below  350  feet  above  tide. 

Table  of  icells  in  Putnam  County,  by  Prof.  J.  A.  Udden. 


Owner  or  location. 

Altitude 
(above  tide). 

Depth. 

Eemark3. 

Feet. 

Feet. 

Mr.   Wheeler,    near    Putnam 

470 

107 

Clay,  12  feet;  sand,  35  feet;  blue  clay,  60  feet ;  sand- 

City.       ^ 

stone  at  bottom. 

C.  Eeed,  sec.  25,  T.  14,  R.  9  E  . . . 

620 

231 

Clay,  16  feet;  gravel,  12  feet;  gray  clay,  85  feet; 
sand  and  gravel,  108  feet;  Coal  Pleasures  at  bot- 
tom. 

F.  Willmann,  sec.  33,  T.   33, 

670 

280 

Clay,  75  feet;   sand,  9  feet;   reddish  clay,  19  feet; 

E.1W. 

saud,  ofeet;  red  clay,  15  feet;  sand,  45  feet;  al- 
ternations of  clay  and  sand  to  bottom;  no  rock. 

Granville  creamery 

670 

135 

Blue  till,  30  feet;  reddish  clay,  50  feet;  saud  and 
gravel,  48  feet;  rock,  7  feet. 

W.  Sill,  860. 17,  T.  32,  R.  1  W  . . . 

710 

114 

No  rook  struck. 

J.  Henning,   sec.    22,    T.    32, 

730 

182 

Yellow  clay,  12feet;  blue  clay,  80  feet;  "hardpau," 

R.  1  W. 

90  feet;  rock  near  bottom. 

Sec.  11,  T.  32,  E.  2  W 

580 

200 

Rock  entered  at  155  feet;    drift  maiuly  sand  and 

gravel. 

Sec.  14,  T.  32,  R.  2  W 

600 
690 
690 
710 

226 
280 
100 
160 

No  rook  struck ;  mainly  bowlder  clay. 
Bottom  in  sand. 

Sec.  5,  T.  31,  R.  1  W 

Sec.  6,  T.  31,  R.  1  W 

Bottom  iu  sand. 

J.  Mills,  sec.  11,  T.  31,  R.  1  W. . . 

Rock  entered  near  bottom. 

J.  Kays,  sec.  30,  T.  31,  R.  1  W. . . 

660 

240 

Maiuly  till;  gravel  at  bottom. 

W.  Glenn,  sec.  31,  T.  31,  R.  1  W . 

670 

160 

In  olay  at  bottom. 

Mount  Palatine 

730 

150 

Mainly  till;  no  rock  struck. 

WELLS  OF  LASALLE  COUNTY,  ILLINOIS.  635 

LASALLE  COUNTY. 
GENERAL   STATEMENT. 

Lasalle  County  is  situated  in  the  north-central  part  of  the  State,  imme- 
diately east  of  Bureau  and  Putnam  counties  and  above  the  bend  of  the 
Illinois  River.  That  river  traverses  the  county  nearly  central  from  east  to 
west.  It  is  the  second  county  in  size,  being  exceeded  only  by  McLean 
County,  and  has  an  area  of  1,152  square  miles.  Ottawa,  the  county  seat, 
is  situated  near  its  geographic  center,  at  the  junction  of  Fox  River  with  the 
Illinois.  Fox  River  traverses  the  northeastern  portion  in  a  southwestward 
course  and  receives  the  drainage  of  much  of  the  northern  half  of  the 
county.  Vermilion  River  traverses  the  southern  portion  of  the  county  in 
a  northwestward  course,  entering  the  Illinois  opposite  the  city  of  Lasalle 
and  dividing  the  portion  south  of  the  Illinois  into  nearly  equal  parts.  The 
Little  Vermilion  drains  the  northwest  portion  of  the  county  in  a  southward 
course  and  enters  the  Illinois  at  Lasalle. 

The  most  elevated  portion  of  the  county  is  in  the  northwest  corner, 
which  is  occupied  by  the  inner  portion  of  the  Bloomington  morainic  system. 
The  altitude  here  reaches  about  900  feet  above  tide.  Much  of  the  uplands 
in  the  county  stand  below  700  feet.  The  extreme  southwestern  portion, 
however,  rises  to  about  750  feet,  and  the  Marseilles  moraine  on  the  eastern 
border  of  the  county  has  a  crest  line  about  750  feet  above  tide.  The 
greater  portion  of  the  surface  is  nearly  plane.  There  is,  however,  aside 
from  the  two  moraines  just  mentioned,  a  small  morainic  belt  (Farm  Ridge) 
which  occupies  the  upland  immediately  east  of  Little  and  Big  Vermilion 
rivers,  crossing  the  Illinois  River  between  Utica  and  Lasalle. 

The  principal  streams  of  the  county  have  excavated  valleys  iii  the  rock, 
and  wells  on  the  uplands  frequently  enter  rock  at  depths  of  50  feet  or  less, 
except  in  the  elevated  portions  referred  to  in  the  northwest,  southwest,  and 
east  parts  of  the  county.  In  the  northwest  part  the  thickness  of  the  drift 
exceeds  200  feet.  In  the  southwest  part  it  is  apparently  about  150  feet.  In 
the  eastern  part,  along  the  Marseilles  moraine,  it  is  200  feet  or  more.  The 
average  distance  to  rock  in  55  of  the  deep  wells  on  the  upland  and  8  deep 
wells  in  the  valleys  is  99  feet.  Records  were  obtained  of  85  other  deep 
wells  which  do  not  enter  rock,  though  their  average  depth  is  89  feet.  They 
are  largely  situated  on  the   Marseilles  moraine.     The  wells  entering  rock 


636  THE  ILLINOIS  GLACIAL  LOBE. 

here  discussed  are  distributed  with  some  imiformity  over  the  entire  count}', 
except  the  portion  southwest  of  Vermihon  River,  where  very  few  records 
have  been  obtained. 

The  upper  portion  of  the  drift,  and  indeed  the  deposit  penetrated  by 
nearly  the  entire  depth  of  the  wells  throughout  the  county,  is  blue  till. 
There  are,  however,  small  areas  in  which  the  drift  contains  a  larger  amount 
of  sand  and  gravel  than  till,  and  thin  beds  of  gravel  or  sand  appear  to  be 
quite  generally  present  in  the  till.  These  afford  water  for  the  shallow  wells 
on  the  farms  and  in  villages.  The  public  wells  in  cities  and  villages  and  the 
stock  wells  on  the  farms  are  iisually  sunk  to  considerable  depth. 

On  the  north  border  of  the  county,  near  Earlville,  many  flowing  wells 
have  been  obtained  from  the  drift,  usually  at  depths  of  25  to  50  feet,  or 
even  less,  but  occasionally  of  greater  depth.  Strong  hydi-ostatic  pressure 
is  exhibited  by  wells  situated  on  the  lower  portion  of  the  slopes  of  the 
large  moraines  in  the  northwestern  and  in  the  eastern  part  of  the  county. 
This  pressure  is  in  all  probability  due  to  absorption  of  the  water  on 
more  elevated  portions  of  the  moraine.  The  flowing  well  district  near 
Earlville  is  thus  related  to  the  moraine  on  the  northwest.  A  few  other 
flowing  wells  occur  in  the  county  in  valleys  or  lowland  tracts,  which  are 
probably  supplied  from  the  neighboring  higher  land. 

Many  artesian  wells  are  obtained  from  the  St.  Peter  sandstone.  Lower 
Magnesian  limestones  and  sandstone,  and  the  Potsdam  sandstone  along  the 
borders  of  the  Illinois  River,  and  occasionally  at  points  on  the  uplands,  as 
appears  in  the  discussion  below. 

INDIVIDUAL   WELLS. 

The  city  of  Mendota,  in  the  northwest  part  of  the  county,  obtains  its 
public  water  supply  from  wells  about  400  feet  in  depth  sunk  to  the  St. 
Peter  sandstone.  A  portion  of  the  water  may  be  derived  from  higher 
horizons.  The  head  is  sufficient  to  bring  the  water  within  4U  feet  of  the 
sui-face,  or  to  about  710  feet  above  tide,  which  is  somewhat  higher  than  the 
head  for  the  St.  Peter  in  this  region.  The  private  wells  at  Mendota  are 
usually  obtained  at  depths  of  but  12  to  20  feet  in  beds  of  sand  or  gravel 
between  the  yellow  and  blue  tills.  A  few  deep  wells  liave  been  sunk  in 
the  vicinity  of  the  city,  which  show  the  di-ift  to  be  160  to  200  feet  in  depth. 
An  old  soil  is  frequently  passed  through  in  the  lower  part  of  the  drift  at  a 
dei)tli  of  100  feet  or  more.     The  till  above  the  soil  is  usually  of  a  blue 


WELLS  OF  LASALLE  COUNTY,  ILLINOIS.  637 

color  and  comparatively  soft,  being  apparently  of  Wisconsin  age.  That 
below  the  soil  is  of  a  brown  or  gra}^  color  and  usually  is  rather  hard. 
Several  gas  wells  have  been  obtained  near  the  level  of  this  old  soil,  as  in 
the  neighboring  portion  of  Bureau  County,  discussed  above.  Here,  as  in 
Bureau  County,  the  gas  is  probably  largely  derived  from  decomposition  of 
the  vegetation  in  the  buried  soils  and  in  the  drift,  but  a  portion  may  be 
derived  by  escape  from  the  underlying  Trenton  limestone. 

At  Earlville,  near  the  north  border  of  the  county,  the  public  water 
supply  is  from  an  8-inch  tubular  well  150  feet  in  depth,  which  terminates 
in  limestone.  The  private  wells  in  that  vicinity  are  30  to  60  feet  in  depth 
and  usually  obtain  water  in  gravel  below  till,  though  a  few  enter  the  rock.-' 

The  public  water  supply  at  the  city  of  Peru  is  obtained  from  an  arte- 
sian well  1,250  feet  in  depth,  which  terminates  probably  above  the  St.  Peter 
sandstone.  Another  well  at  the  zinc  works  in  Peru,  1,360  feet  in  depth, 
obtains  its  supply  from  the  St.  Peter  at  the  bottom  and  probably  in  part 
from  the  limestones  above  this  sandstone.  The  waterworks  well  is  estimated 
to  have  a  capacity  of  450  gallons  per  minute  and  its  head  is  sufficient  to 
cause  an  ovei-flow  at  85  feet  above  the  well  mouth  or  560  feet  above  tide. 
An  analysis  of  the  water  has  been  published  in  the  Seventeenth  Annual 
Report  of  this  Survey.^  This  analysis  shows  but  16  grains  of  sodium 
chloride  per  gallon  and  the  water  is  considered  of  excellent  quality.  There 
is  about  130  feet  of  drift  in  the  Illinois  Valley  at  this  point.  This  gives 
the  rock  floor  an  altitude  but  330  feet  above  tide,  which  is  fully  as  low  as 
at  wells  in  this  valley  in  Bureau  and  Putnam  counties.  This  city  seems  to 
stand  a  few  miles  east  from  the  main  preglacial  valley. 

The  city  of  Lasalle  obtains  its  public  water  supply  in  part  from  springs 
and  in  part  from  two  artesian  wells  obtained  in  the  Goal  Measures  sand- 
stone at  depths  of  332  and  530  feet.  The  springs  yield  about  1,500,000 
gallons  a  day  and  the  wells  about  one-third  that  amount  (C.  H.  Nicolet, 
city  engineer.)  Many  private  wells  are  obtained  in  Lasalle  at  depths  of 
10  to  30  feet  in  gravel  near  the  base  of  the  drift.  The  Illinois  River  from 
Lasalle  eastward  being  outside  the  line  of  the  preglacial  valley,  which  it 
enters  west  of  this  city,  rock  is  found  at  comparatively  slight  depths  in  the 
valley  bottom. 

'  The  flowing  wells  near  Earlville  are  discussed  in  the  Seventeenth  Annual  EeBort  of  this  Survey 
(Part  II,  pp.  779-780). 
-  Part  II,  p.  828. 


638  THE  ILLINOIS  GLACIAL  LOBE. 

At  the  villag-e  of  Utica  many  artesian  wells  have  been  obtained  in  the 
Lower  Magnesian  limestone.  The  strongest  wells  are  obtained  at  depths 
of  215  to  330  feet,  but  many  are  of  much  less  depth.  The  water  rises  to  a 
height  of  about  50  feet  above  the  surface,  or  525  feet  above  tide.  The 
sti'ongest  wells  have  an  estimated  capacity  of  about  150  gallons  a  minute, 
or  200,000  gallons  a  day. 

Tlae  city  of  Ottawa  formerly  obtained  much  of  its  public  water  supply 
fi'om  shallow  wells  piped  to  a  reservoir  on  the  south  bluff  of  the  river  and 
disti'ibuted  by  g•ra^^ty  to  the  city.  It  is  now  supplied  from  sis  artesian 
wells  and  Fox  River.  A  lai'ge  number  of  private  artesian  wells  are  sunk 
through  the  St.  Peter  sandstone  to  the  underlying  strata,  from  which  an 
excellent  quality  of  water  overflows.  It  is  estimated  that  there  are  not 
less  than  200  such  wells  in  the  (dty  and  vicinity.  The  great  majority  are 
but  300  to  400  feet  in  depth.  One  boring  was  sunk,  however,  to  a  depth 
of  1,840  feet  and  obtained  water  from  the  Potsdam,  which  has  a  sti'ong 
■flow  in  the  lower  200  feet.  The  head  is  estimated  to  reach  175  feet  above 
the  well  mouth,  or  705  feet  above  tide  The  quality  of  the  water  is  vari- 
able in  the  several  wells,  but  is  usually  slightly  sulphurous  and  moderately 
hard.     The  salinity  is  very  slight. 

At  the  village  of  Marseilles  a  large  number  of  private  artesian  wells 
have  been  sunk  which  obtain  water  from  the  St.  Peter  sandstone  at  depths 
of  100  to  200  feet.  The  head  is  remarkably  low,  being  but  12  to  20  feet 
above  the  surface,  or  scarcely  500  feet  above  tide.  The  wells  are  ordi- 
narily but  2  inches  in  diameter,  with  a  nozzle  1  inch  in  diameter.  Their 
rate  of  flow  has  appreciably  decreased  within  the  past  15  years  and  at  pres- 
ent an  average  well  will  discharge  but  4  or  5  gallons  a  minute.  For  fire 
purposes  the  village  has  a  system  of  waterworks  which  pumps  its  supply 
from  the  Illinois  River. 

The  villao-e  of  Seneca,  situated  in  the  Illinois  Vallev  near  the  east 
border  of  the  county,  is  also  supplied  with  several  private  artesian  wells, 
which  obtain  water  from  the  St.  Peter  or  lower  strata  at  depths  ranging 
from  350  to  680  feet.  The  strongest  How  is  thought  to  be  obtained  at  a 
depth  of  about  630  feet.  The  water  is  slightly  sulphurous,  but  is  other- 
wise of  pleasant  taste.  The  head,  like  that  of  the  wells  at  Marseilles,  is 
remarkably  low,  being  scarcely  more  than  20  feet  above  the  surface  at  the 
wells,  or  525  feet  above  tide. 


WELLS  OF  LASALLE  COUNTY,  ILLINOIS. 


639 


Streator,  a  city  located  on  the  southern  border  of  the  county,  obtains 
its  public  supply  by  pumping  from  Vermilion  River.  Many  private  wells 
are  obtained  at  depths  of  20  to  40  feet,  from  gravel  in  the  drift.  An  artesian 
well  was  sunk  in  this  city  to  a  depth  of  2,496  feet,  terminating  in  the 
Potsdam  sandstone.  Water  was  struck  in  the  St.  Peter  sandstone  at  450 
feet,  which  has  a  head  678  feet  above  tide,  or  40  feet  below  the  surface. 
In  the  Lower  Magnesian  strata  the  head  was  increased  a  few  feet,  and  in 
the  Potsdam,  at  2,170  to  2,496  feet,  water  was  struck  which  has  a  head 
45  feet  above  the  surface,  or  663  feet  above  tide.  A  section  of  this  well 
and  also  of  the  deepest  well  at  Ottawa  has  been  published  in  the  Seven- 
teenth Annual  Report  of  this  Surve}^.^ 

At  Vermilionville,  in  the  valley  of  Vermilion  River,  a  few  miles  below 
Streator,  a  boring  made  for  oil  reached  a  depth  of  1,000  feet  and  obtained 
a  strong  flow  of  excellent  water.  Numerous  springs  occur  along  the  Ver- 
milion River  below  Streator,  which  are  in  part  from  the  St.  Peter  and  in 
part  from  Coal  Measures.     The  water  is  usually  of  excellent  quality. 

An  artesian  well  2,189  feet  in  depth  was  made  by  Mr.  Pedicord  on  the 
uplands  north  of  the  Illinois  River  near  Marseilles,  at  an  altitude  about  700 
feet  above  tide.  When  cased,  an  overflow  from  a  depth  of  1,850  feet  was 
obtained.     The  well  penetrated  169  feet  of  glacial  drift.^ 

The  following  table  of  deep  wells  along  the  Marseilles  moraine  begins 
in  the  northeast  part  of  the  county  and  proceeds  southward.  The  moraine 
is  situated  immediately  east  of  Fox  River  as  far  south  as  the  mouth  of  that 
stream.  Upon  crossing  the  Illinois  it  bears  east  of  south,  leaving  the  county 
near  the  southeast  corner.     The  width,  including  the  slopes,  is  5  or  6  miles. 

Wells  along  the  Marseilles  moraine  in  eastern  Lasalle  County. 


Owner  or  location. 

Altitude 
(above  tide) . 

Depth. 

Eemarks. 

Feet. 

Feet. 

Sec.  23,  T.  35,  R.  5  E 

675 

137 

St.  Peter  sandstone  at  130  feet;  drift  mainly  blue 
till. 

See.23,  T.35,  R.5E    

650 

100 

Three  "wells  about  100  feet    with  no  ronV 

Sec.  33,  T.  35,  R.  5  E 

700 

153 

St.  Peter  sandstone  at  bottom;  drift  mainly  blue 
till. 

Sec.  4,  T.  34,  R.  5  E 

720 

233 

Till,  138  feet ;  sand  and  gravel,  13  feet ;  blue  clay,  17 
feet;  St.  Peter  simdstone,  65  feet. 

Sec.  0,  T.  34,  R.  5  E 

650 

105 

strikes  rock  at  bottom. 

'Part II,  pp.  798-799. 


-  Geol.  of  Illinois,  Vol.  VII,  p.  50. 


640  THE  ILLmOiC  GLACIAL  LOBE. 

Wells  along  the  Marseilles  moraine  in  eastern  Lasalle  County — Continued. 


Owuer  or  location. 


Altitude 
(above  tide) 


Depth. 


Remarks. 


Sec.  5,  T.  34,  K.  5  E 


Sec.  9,  T.  3i,  R.  5  E  .. 

Sec.  6,  T.  34,  R.  5  E  . . 
Sec.  9,  T.  34,  R.  5  E  . . 
Sec.  16,  T.  34,  R.  5  E  . 

Sec.  18,  T.  .34,  R.  .5  E  , 
Sec.  27,  T.  34,  R.  5  E 
Sec.  22,  T.  34,  E.  5  E 
Sec.  24,  T.  34,  R.  5  E  . 
Sec.  28,  T.  34,  R.  5  E  , 
Sec.  11,  T.  34,  E.  4  E  . 


Sec.l4,T.34,R.4E... 
Dan  way  and  vicinity. 


Sec.  13,  T.  34,  R.  4  E  . 
Sec.  23,  T.  34,  R.  4  E  . 


Sec.  34,  T.  34,  R.  4  E  , 


Sec.  35,  T.  34,  E.  4  E 

Sees.  3  and  4,  T.  33,  E.  5  E  . 


A.  Irwin,  bluff  north  of  Seneca 

Sec.  20,  T.  38,  E.  4  E 

Sec.  26,  T.  33,  R.  4  E , 

Sec.  26,  T.  33,  R.  4  E 


Bluff  south  of  Marseilles. 

Sec.  36,  T.  33,  E.  4  E 

Sec.  21,  T.  33,  E.  5  E 

Sec.  1,  T.  32,  E.  4  E 

Sec.  2,  T.  32,  E.  4  E 

Sec.  2,  T.  32,  R.  4  E 

Sec.  35,  T.  32,  R.  4  E 

Sec.29,T.32,R.5E 

Sec.  30,  T.  32,  R.  5  E 


Feet. 
675 


700 


Feet. 
160 


196 


650 

100 

675 

210 

700 

200 

700 

200 

650 

160 

700 

185 

650 

100 

700 

180 

650 

195 

650 

100 

690 

100 

675 

107 

650 

118 

620 

68 

650 

85 

650 

610 

108 

630 

215 

740 

219 

720 

252 

675 

184 

700 

177 

675 

80 

740 

232 

725 

220 

725 

194 

700 

108 

700 

130 

700 

128 

Till,  100  feet ;  sand,  10  or  15  feet ;  clay,  10  or  15  feet ; 

Coal  Measures  shale,  etc.,  35  feet;  St.  Peter  sand- 
stone near  bottom. 
St.  Peter  sandstone  near  bottom;   hard  brown  till 

below  blue  till  at  166  feet. 
Mainly  sand  and  gravel ;  no  rock. 
No  rock  struck. 
St.  Peter  (?)  sandstone  entered  near  bottom  below 

drift, 
lu  gravel  at  bottom. 
St.  Peter  (  f )  sandstone  at  bottom. 
No  rock  struck. 

Coal  Measures  sandstone  at  bottom. 
Mainly  till ;  hard  rock  at  bottom. 
Till,  93  feet;  gravel,  7  feet;    "potter's  clay,"  40 

feet;  sandstone,  55  feet ;  St.  Peter  sandstone  near 

bottom. 
In  sand  below  till. 
Several    wells  100  feet  deep   do  not  enter  rock; 

mainly  through  till. 
Three  wells,  100  to  107  feet ;  mainly  through  till ; 

no  rock. 
Yellow  till,  15  feet;  blue  till,  75  feet;  black  clay  or 

soil,  8  feet;  sand,  20  feet;  no  rock. 
Soft  till,  28  feet;  hard,  dry  till,  40  feet;  rock  at 

bottom. 
No  rock;  mainly  blue  till. 
Molluscan  shells  in  sand  at  6  to  10  feet;  wells,  10 

to  33  feet. 
No  rock;  mainly  till. 

Drift,  40  feet;  St.  Peter  sandstone  at  215  feet. 
Till,  170  feet;  sand  and  till  to  bottom. 
Till,  198  feet;  gray,  sandy  clay,  38  feet;  sandstone, 

14  feet;  shale,  2  feet. 
Till,  165  feet;  sand  and  gravel  to  bottom. 
Till,  170  feet;  sand  at  bottom. 
Yellow  clay,  10  feet;  gravel,  70  feet. 
Till,  1.50  feet ;  remainder  sand  and  till. 
Till,  150  feet;  remainder  sand  and  till. 
Till,  116  feet;  s.iud  and  till  to  bottom. 
Entirely  through  till. 
Eniirely  through  till. 
Till,  125  feet;  saud  at  bottom. 


WELLS  OF  LASALLE  COUNTY,  ILLINOIS.  641 

Wells  along  the  Marseilles  moraine  in  eastern  Lasalle  County — Continued. 


Owner  or  location. 

Altitude 
(above  tide). 

Deptli. 

Remarks. 

Feet. 

Feet. 

Sec.  9  T.  31,  E.5  E 

720 

181 

Eoct  ^  at  bottom 

Sec.  14,  T.  31,  E.  5  E 

690 

103 

Mainly  till ;  rock  at  bottom. 

Drift,   mainly  till,   285   feet;   Coal  Measures  and 

Mr.  Gate,  near  Ransom 

720 

543 

limestone    (Trenton?)    extending    to    St.   Peter 

sandstone  at  510  feet. 

S.  deals,  near  Ransom 

720 

370 

Drift,  mainly  till,  270  feet;  Coal  Measures,  100  feet; 
limestone  (Trenton?)  near  bottom. 

Sec.5,  T.31,  E.5  E 

720 

144 

Mainly  till;  sand  at  bottom. 

Sec.  35,  T.  31,  E.  5  E 

700 

130 

Sec.36,  T.  31,  R.5E 

675 

160 

Enters  rock  at  120  feet 

Sec.  27,  T.  31,  E.  5  E 

700 

175 

Gas   well    from  drift  sand;   water   stands   6  feet 
below  surface. 

Sec.  36,  T.  31,  E.  4E. ;  also  sees. 

700 

160 

Several  wells  about  160  feet ;    none  enter  rock. 

25  and  26. 

The  following  table  includes  the  deepest  well  sections  obtained  in  other 
parts  of  the  county  aside  from  the  artesian  wells  discussed  above  :^ 

Wells  of  Lasalle  County  outside  the  Marseilles  moraine. 


Owner  or  location. 

Altitude 
(abovetide). 

Depth. 

RemarUd. 

Feet 

Feet. 

Sec.  11,  T.  36,  E.  5  E    . 

650 

80 

Eive  wells  enter  first  rock  at  about  20  feet  and 
St.  Peter  sandstone  at  35  or  40  feet. 

Sec.  11,  T.  36,  E.  5  E    . 

650 

20 

Black  muck  with  wood  and  leaves  below  till  at 
bottom. 

Sec.  9,  T.  36,  E.  3  E 

700 

180 

Boring  for  coal  struck  old  soil  at  35  to  40  feet  and 
entered  rock  at  50  feet. 

Sec.  9,  T.  36,  E.  3  E 

680 

20 

Two  flowing  wells  in  Indian  Creek  Valley. 
Thirty  flowing  wells  18  to  85  feet  in  depth  from 

T.  36,  Es.  2  and  3  E 

690 

sand  below  till. 

D.  Ivnight,  sec.  34,  T.  36,  E.  4  E. 

675 

80 

Enters  rock  at  63  feet;  well  half  mile  west  enters 
rock  at  63  feet. 

NW.  part  of  T.  36,  E.  1  E 

850 

200 

Several  wells  150  to  200  feet,  with  no  rock. 

li  miles  north  of  Mendota 

800 

198 

Gas  at  75  and  128  feet;  old  soil  at  178  feet;  water 
rises  90  feet  from  gravel  at  bottom. 

Mr.  Miller,  near  Mendota 

725 

144 

Flowing  well  from  gravel  below  till ;  a  buried  soil 
from  120  to  125  feet. 

'For  sections  of  several  wells  in  the  vicinity  of  Mendota  the  writer  is  indebted  to  Mr.  L.  E. 
Curtis  of  that  city. 

MON  XXXVIII 4:1 


642  THE  ILLINOIS  GLACIAL  LOBE. 

Wells  of  Lasalle  County  outside  the  Marseilles  moraine — Continued. 


Owuer  or  locution. 

Altitude, 
(above  tide). 

Beptb. 

Remarks. 

Feet. 

Feet. 

Porterfield's    gas   wells  near 

700  to  725 

176 

Five  wells   120  to   176  feet ;  deepest  reaches  rock ; 

Mendota, 

black  muck  or  soil  with  leached  subsoil  between 
till  sheets  at  about  600  feet  above  tide;  gas  in 
sand  above  old  soil. 

Blaucliard's    gas    well,    near 

750 

218 

Yellow  till,  10  feet;   blue  till,  56   feet;  sand  with 

Mendota. 

gas,  96  feet ;  Trenton  limestone,  56  feet. 

Sec.  26,  T.  35,  R.  1  E 

610 

46 

Trenton  limestone  at  46  feet. 

Mr.  Fiufsen,  6  miles   S.  from 

700 

143 

Well  enters  Coal  Measures  shale  below  drift  at  143 

Mendota. 

feet. 

Sec.  32  T.  35  R.  1  E 

650 

40 

Gas  from  trravel  below  till. 

Sec.  26,  T.  35,  R.  2  E 

700 

121 

Three  wells  of  similar  depth  and  structure :  yellow 
till,  16  feet;  blue  till,  85  feet ;  gravel,  20  feet. 

Sec.  23,  T.  35,  R.  2  E 

660 
675 

63 

54 

Sec.  32  T.  35,  R.  2  E 

No  rock;  mainly  till. 

Rock  at  bottom;  mainly  till.     Two  wells. 

No  rock ;  mainly  blue  till. 

No  rock;  maiuly  blue  till. 

Entirely  till. 

Till,  40  feet;  sand  and  gravel,  64  feet. 

Sec.  35,  T.  35,  R.  2  E 

700 

98 

Sec.  34,  T.  35,  R.  2  E  .   .     . . 

675 

76 

Sec.  5.  T.  34,  R.  2  E 

700 

80 

Sec.  4,  T.  34,  R.  2  E 

700 

91 

J.  Bo  wen,  near  Serena 

600 

104 

H.  Bowen,  near  Serena 

600 

75 

Enters  sandstone  at  bottom. 

635 

100 

Mainly  blue  till,  50  or  60  feet;  sand  and  gravel.  15 
or  20  feet;  St.  Peter  sandstone  at  75  or  100  feet. 

641 
591 
620 

40 

16 

100 

Mainly  till;  no  rock. 

St.  Peter  sandstone  at  12  to  16  feet. 

Sec  27  T.  33  R.2  E           .     ... 

No  rock ;  mainly  till. 
No  rock :  mainly  till. 

Sec.33  T.33,R.2  E    

620 

100 

Sec.  23  T.  33,  R.  5  E    

600 

88 

Very  hard  red  till  near  bottom  under  soft  blue  till. 

Sec.5,  T.33,  R.2E 

650 
625 

47 
50 

Sec.  28,  T.  33,  R.  2  E 

Rook  at  50  feet. 

585 

30 

Gravel,  30  feet ;  till  at  bottom. 

Ottawa  waterworks 

600 

27 

Mainly  gravel  and  sand;  no  rock. 

Till,  120  feet;  saud  and  gravel  to  bottom. 

Orand  Ridge  Station 

663 

153 

Sec.  21  T.  32,  K.  3  E    , 

650 

200 

Till,  140  feet;  sand  and  gravel,  60  feet. 

Mainly  sand ;  no  rock. 

No  rock;  blue  clay  with  some  sand. 

Farm  Ridge 

680 

50 

R.  Williams,  9  miles  north  of 

650 

140 

Streator. 

One  mile  from  preceding 

(i50 

187 

Water  rises  87  feet. 

One  mile  from  preceding 

650 

315 

St.  Peter  sandstone  at  bottom ;  water  brackish. 

Sec  17  T.  32,  R.  1  E 

675 

150 

Till  about  50  feet;   sand  about  100  feet;    rocli   at 

bottom. 

Sec  18  T  31  R  4  E 

610 
660 

65 
100 

Mainly  saud  and  gravel;  shale  at  bottom. 
No  rock ;  entirely  till. 

Sec  34.  T.  31,  R.  4  E      

WELLS  OF  KENDALL  COUNTY,  ILLINOIS.  643 

KENDALL  COUNTY. 
GENEKAL  STATEMENT. 

Kendall  is  a  small  county,  with  an  area  of  but  330  square  miles,  sit- 
uated east  of  tlie  northern  part  of  Lasalle  and  the  southern  part  of  Dekalb 
County,  with  Yorkville  as  the  county  seat.  Fox  River  crosses  its  north- 
western portion  in  a  southwestward  course,  and  nearly  half  the  county  is 
tributary  to  it.  The  remainder  of  the  county  di-ains  southeastward  directly 
to  the  Illinois  River  through  Aux  Sable  Creek  and  smaller  streams. 

The  Marseilles  moraine  traverses  this  county  centrally  from  northeast 
to  southwest,  following-  the  southeast  border  of  Fox  River  Valley,  or  rather 
Fox  River  Valley-  follows  the  outer  border  of  this  moraine,  the  course  of 
the  stream  being  determined  by  the  moraine.  The  remainder  of  the  county 
has  a  plane  surface,  except  the  east  border,  which  is  occupied  by  the 
Minooka  till  ridge.  The  drift  is  of  moderate  thickness,  averaging  probably 
100  feet.  A  small  area  in  the  southern  part  is  very  thinly  coated  and  there 
are  numerous  rock  outcrops  along  the  Fox  River  Valley.  The  heaviest 
drift,  apparentl}',  is  along  the  line  of  the  Marseilles  moraine,  where,  as 
shown  in  the  table  below,  the  thickness  usually  exceeds  150  feet. 

An  extensive  gravelh'  area  occupies  townships  bordering  Fox  River. 
The  gravel  extends  usually  as  deep  as  wells  have  penetrated,  and  may  con- 
tinue to  the  underlying  rock.  The  remainder  of  the  county  outside  the 
moraine  apparently  has  much  sand  and  gravel  in  the  lower  part  of  the  drift. 
The  Marseilles  moraine  and  the  plain  to  the  southeast  are  characterized  by 
a  heavy  sheet  of  till,  though  there  are  limited  areas  in  which  wells  pene- 
trate a  large  amount  of  sand  or  gravel.  The  Minooka  Ridg'e,  also,  is  com- 
posed largel}'  of  till.  Wells  are  ordinarily  obtained  in  this  county  at  de^jths 
of  25  to  35  feet.  The  deeper  ones  are  largely  found  along  the  Marseilles 
and  Minooka  ridges. 

INDIVIDUAL    WELLS. 

At  Piano,  in  the  northwest  part  of  the  county,  several  wells  reach  a 
depth  of  45  feet  without  entering  rock,  and  are  mainly  tlu'ough  sand  and 
gravel.  The  public  water  supply  is  from  a  well.'  North  of  this  village 
for  2  or  3  miles  wells  usually  peneti'ate  about  20  feet  of  till  and  then  enter 
sand  and  gravel,  in  which  they  terminate  at  depths  of  40  or  50  feet.     One 

'  Manual  of  American  Waterworks.  1897. 


g44  THE  ILLINOIS  GLACIAL  LOBE. 

well,  however,  in  see.  11,  was  sunk  to  a  depth  of  196  feet  and  entered  rock 
at  about  150  feet.  Mr.  Otis  Latham  made  a  well  in  Piano  which  struck  an 
old  soil  containing-  grass  leaves  beneath  till  at  a  depth  of  about  25  feet. 
Southwest  of  Piano,  in  sees.  29  and  31,  two  wells  44  and  69  feet  in  depth 
are  mainlv  tln-ouo-h  sand,  and  do  not  enter  rock. 

At  Oswego  there  is  a  very  thin  coating  of  gravelly  drift  on  the  rock, 
and  wells  are  usually  sunk  into  the  limestone  about  to  the  level  of  Fox 
River,  30  or  40  feet.  The  public  water  supply  is  from  drilled  wells.'  For 
about  5  miles  below  Oswego  there  is  a  gravel  plain  on  the  east  side  of 
Fox  River  a  mile  or  more  in  width,  on  which  wells  are  obtained  at  depths 
of  10  to  30  feet  without  entering  rock. 

At  Yorkville  the  public  water  supply  is  obtained  from  springs  in  the 
Marseilles  moraine  which  borders  the  town  on  the  southeast.  The  private 
wells  are  obtained  at  depths  of  15  to  30  feet  and  seldom  enter  the  rock. 

At  Millington  flowing  wells  may  be  obtained  from  the  St.  Peter  sand- 
stone at  slight  depth.  Two  at  the  residence  of  Dr.  J.  A.  Freeman,  78  feet 
in  depth,  enter  this  sandstone  27  feet.  The  drift,  with  the  exception  of 
about  20  feet  of  gravel  at  surface,  is  mainly  till.  The  wells  are  ordinarily 
obtained  in  this  village  at  depths  of  12  to  20  feet  in  the  gravel  of  the  Fox 
River  Valley. 

In  the  vicinity  of  the  village  of  Plattville  on  the  plain  east  of  the 
Marseilles  moraine  many  flowing  wells  have  been  obtained.  The  majority 
have  a  depth  of  but  30  to  45  feet,  but  occasionally  a  depth  of  70  feet  or 
more  is  reached.  The  water  is  obtained  in  sand  below  till  and  the  absorb- 
ing area  is,  in  all  probability,  in  the  Marseilles  moraine  on  the  west.  A 
deep  well  2  miles  north  of  Plattville  at  an  altitude  about  50  feet  above  the 
village,  or  650  feet  above  tide,  reached  a  depth  of  550  feet  and  entered  St. 
Peter  sandstone  at  511  feet.  A  large  amount  of  water  is  obtained,  but  it 
does  not  overflow.  Rock  was  entered  at  143  feet  and  is  mainly  limestone 
down  to  the  St.  Peter  sandstone.  A  well  1^  miles  east  of  Plattville  at 
about  the  same  elevation  (600  feet)  entered  rock  at  40  feet  and  was  drilled 
to  a  depth  of  80  feet. 

In  the  vicinity  of  Lisbon,  where  the  altitude  is  625  to  640  feet,  limestone 
is  entered  at  a  depth  of  10  feet  or  less,  and  wells  are  obtained  at  depths  of 
only  30  to  50  feet.     For  4  or  5  miles  northeast  of  Lisbon  rock  is  usually 

'  Mauuul  of  American  Waterworks,  1897. 


WELLS  OF  KENDALL  COUNTY,  ILLINOIS. 


645 


entered  at  less  than  50  feet,  but  occasionally  a  well  reaches  a  depth  of  90 
feet  without  entering  it.  Three  wells  in  sees.  11  and  12,  T.  35,  R.  7  E.,  are 
48,  50,  and  90  feet  in  depth  without  reaching'  rock,  and  the  water  has  a  head 
nearly  level  with  the  surface.  The  altitude  is  about  40  feet  lower  than  at 
Lisbon,  or  600  feet  above  tide. 

The  following-  list  of  wells  along  the  Marseilles  moraine  include  the 
deepest  of  which  records  were  obtained.  Many  shallower  wells  occru- 
which  obtain  water  at  depths  of  30  to  40  feet  or  less.  The  sections  are 
taken  in  order,  beginning  at  the  northeast  corner  of  the  county  and  passing 
southwestward : 

Wells  on  the  Marseilles  moraine  in  Kendall  County. 


Owner  or  location. 

Altitude 
(above  tide). 

Depth. 

Kemarks. 

Feet. 

Feet. 

Sec.  24,  T.  37,  E.  8  E 

700 
750 

200 
152 

Enters  rock  at  about  200  feet. 

Sec.  24,  T.  37,  R.  8  E 

Yellow  till,  18  feet ;  blue  till,  108  feet ;  sand  with 

clay  streaks,  24  feet ;  gravel  at  bottom. 

Mr.  Miner,  4  miles  southeast  of 

700 

121 

No  rock;  till  100,  sand,  21  feet. 

Oswego. 

Sees.  31  and  32,  T.  37,  R.  8  E  ... 

700 

100 

Several  wells;  mainly  till;  no  rock. 

Sec.  5,  T.  36,  R.  8  E 

725 

150 

Enters  rock  at  about  100  feet. 

Sees.  22  and  28,  T.  36,  R.  6  E  . . . 

675 

120 

Several  wells;  mainly  blue  till;  no  rock. 

G.  Whitfield,  near  Millbrook  . . 

650 

60 

Sand  below  till. 

Mr.  Darnell,  2  miles  south  of 

700 

190 

Mainly  blue  till,  160  feet;  old  soil  with  wood,  2  to 

Millbrook. 

4  feet;  blue  sand  to  bottom. 

Newark  village  Avell 

640 

700 

110 

141 

No  rock;  mainly  till. 

C.  Sleezer,  east  of  Newark 

Mainly  till ;  rock  at  bottom. 

F.  Sleezer,  east  of  Newark 

700 

140 

Entirely  till. 

S.  Sleezer,  east  of  Newark 

725 

160 

No  water  or  rock  struck. 

I.  Anderson,  east  of  Newark  .. 

725 

160 

Soft  till,  100  feet;  hard  till  with  wood  near  bottom, 
60  feet;  St.  Peter  sandstone  at  bottom. 

Sec.  4,  T.  35,  R.  6  E 

725 
725 

150 
161 

Entirely  in  till. 
Limestone  at  bottom. 

Sec.  4,  T.  35,  R.  6  E 

Holderman's  Grove 

700 

50 

Mainly  till;  no  rock. 

Big  Grove 

725 

150 

Two  wells  enter  limestone  below  till  at  this  depth. 

GRUNDY  COUNTY. 
GENERAL  STATEMENT. 


Grundy  County  is  situated  east  of  Lasalle  County  and  includes  the 
head  of  the  Illinois  River.     It  has  an  area  of  440  square  miles,  and  Morris 


646  THE  ILLINOIS  GLACIAL  LOBE. 

is  the  county  seat.  The  Illinois  River  leads  westward  througli  the  nortli- 
centi'al  portion  of  the  county.  The  tributaries  of  the  Illinois,  however, 
have  an  eastward  course,  those  on  the  north  bearing  southeast,  and  those 
on  the  south  northeast.  This  peculiar  feature,  as  previouslv  indicated,  is 
occasioned  by  the  slopes  of  the  plain,  or  basin,  encircled  on  the  north,  west, 
and  south  by  the  Marseilles  moraine,  from  which  there  is  a  gradual  descent 
to  the  center  of  the  basin  near  the  head  of  the  Illinois  River.  The  river  has 
cut  this  moraine  at  the  town  of  Marseilles  and  thus  opened  an  outlet  from 
the  basin. 

The  surface  of  this  county  is  almost  entirely  a  smooth  plain.  The 
Minooka  Ridge  touches  a  few  square  miles  in  the  northeast  corner  of  the 
county  and  the  inner  slope  of  the  Marseilles  moraine  touches  the  extreme 
noi'thwest  and  southwest  corners.  In  the  eastern  jiart  there  are  a  fe.w  dunes 
which  diversif}'  the  otherwise  monotonous  plain. 

In  the  lowest  part  of  the  basin  and  along  the  Illinois  River  the  drift  is 
thin  and  wells  ordinarily  enter  the  rock.  On  the  Minooka  Ridge  the  drift 
probably  averages  at  least  100  feet  and  wells  have  occasionally  been  sunk 
beyond  that  depth  without  entering  rock.  On  rising  toward  the  ^Marseilles 
moraine  in  the  western  portion  of  the  county  there  is  a  corresponding 
increase  in  thickness  of  drift,  and  rock  is  not  found  at  less  than  100  feet 
near  the  western  line  of  the  county,  except  in  the  trench  cut  by  the  Illinois 
River. 

The  eastern  poiidon  of  the  county  is  covered  with  sand,  which  was 
probably  deposited  by  a  lake  occupying  that  portion  of  the  basin.  The 
depth  is  usually  but  a  few  feet  and  the  underlying  drift  is  mainly  blue  till. 
The  slopes  of  the  Marseilles  moraine  in  the  western  part  of  the  county,  and 
the  Minooka  Ridge  in  the  northeastern  part,  rise  above  the  level  of  this  sand 
and  are  composed  mainly  of  blue  till  to  the  depth  ordinarily  reached  by 
wells,  25  to  50  feet  or  more. 

The  low  portion  of  the  county  affords  a  favorable  condition  for  obtain- 
ingr  flowing-  wells  from  the  St.  Peter  sandstone  and  lower  strata,  and  several 
such  wells  have  been  sunk.  A  few  flowing  wells  have  been  obtained  from 
the  drift  on  the  slopes  of  the  Marseilles  moraine  and  there  is  usually  suffi- 
cient hydrostatic  pressure  to  bring  the  water  nearly  to  tlie  surface  through- 
out the  county.  It  is,  therefore,  highly  favored  in  conditions  for  obtaining 
water. 


WELLS  OF  KENDALL  COUNTY,  ILLINOIS.  647 

INDIVIDUAL    WELLS. 

At  Morris  the  public  water  supply  is  obtained  from  artesian  wells 
about  600  feet  in  depth  which  tei-minate  in  the  St.  Peter  sandstone.  The 
head  is  sufficient  to  raise  the  water  a  few  feet  above  the  surface.  Shallow 
wells  are  obtained  in  the  vicinity  of  this  city,  at  depths  of  14  to  30  feet, 
either  in  gravel  or  in  sandy  shale  of  the  Coal  Measures. 

At  Minooka  a  boring  was  sunk  to  a  depth  of  2,100  feet,  which  terminated 
in  the  Potsdam  sandstone.  A  very  strong  water  vein  was  struck  at  about 
1,985  feet,  with  sufficient  head  to  rise  46  feet  above  the  surface,  or  660  feet 
above  tide.  Although  situated  on  the  crest  of  the  ridge,  wells  are  obtained 
in  this  village  at  depths  of  30  or  40  feet. 

At  Carbon  Hill  the  public  water  supply  is  from  an  artesian  well  1,900 
feet  in  depth,  from  which  water  flows  direct  through  the  mains.^ 

At  Coal  City  wells  are  usually  obtained  at  about  12  feet  in  the  sand 
which  covers  that  portion  of  the  county.  The  waterworks  are  used  for  fire 
protection  only.^ 

At  Braceville  wells  are  found  at  the  bottom  of  the  sand  and  also  beneath 
the  till  at  depths  of  30  or  40  feet.  Rock  is  entered  at  Braceville  at  about 
45  feet. 

At  Gardner  wells  are  usually  obtained  from  gravel  or  sand  below  till 
at  40  or  50  feet.  Coal  shafts  enter  rock  at  about  60  feet.  Mr.  Thomas 
Cumming,  of  Gardner,  one  of  the  State  mine  inspectors,  reports  that  water 
veins  of  excellent  quality  are  found  at  several  horizons  in  the  Coal  Measures 
in  the  vicinity  of  the  villages  just  mentioned.' 

At  Mazon  wells  are  ordinarily  obtained  at  depths  of  30  or  40  feet,  but 
several  deep  wells  have  been  made  on  farms  in  that  vicinity  which  do  not 
reach  rock  at  a  depth  of  100  feet.     The  drift  is  mainly  a  blue  till. 

At  Verona,  and  over  an  area  of  several  square  miles  in  the  vicinity  of 
that  village,  sandstone  is  usually  entered  at  about  75  feet. 


'  Manual  of  American  Waterworks,  1897.  ^  Communicated  to  the  writer. 


648  THE  ILLINOIS  GLACIAL  LOBE. 

The  following  well  records  include  the  deepest  obtained  in  the  county: 
Table  of  wells  hi  Grundy  County. 


Owner  and  location. 

Altitude 
(above  tide). 

Depth. 

Kemarks. 

Feet. 

Feet. 

S.  Frey,  W.  part  T.  34,  K.  6  E . . . 

680 

190 

Drift,    mainly   till,  140   feet;    sandstone,    12   feet; 
shale,  38  feet.     .St.  Peter  sandstone  at  bottom. 

I.  Hoge,  jr.,  ,sec.  15,  T.  34,  R.  6  E 

600 

58 

Flowing  well  from  drift. 

S.  Hoge,  sec.  22,  T.  34,  R.  6  E  . . . 

600 

54 

Flowing  well  from  drift. 

0.  Dix,  sec.  8,  T.  34,  R.  6  E 

650 

300 

Drift,  96  feet;  limestone,  100  feet;   sandstone,  105 
feet. 

Mr.  Morwick,  near  iireceding.. 

650 

300 

Drift,  100  feet.     Section  as  in  preceding. 

Sees.  23,  24,  25,  and  26,  T.  34, 

575 

60 

Shale  below  drift  near  bottom. 

E.6E. 

Sees.  21  and  26,  T.  34,  R.  6  E  . . . 

600 

125 

Rock  near  bottom. 

Sees.  15,  16,  21,  and  22,  T.  34, 

575 

50 

Shale  below  till  at  abont  50  feet. 

R.7E. 

Sees.  23  and  27,  T.  34,  R.  7  E  . . . 

550 

24 

Wells  in  sand  below  till. 

Sees.  28  and  33,  T.  34,  E.  7  E  . . . 

540 

30 

Shale  below  till  at  abont  30  feet. 

I.  Hoge,  sec.  31,  T.  34,  R.  7  E . . . . 

550 

42 

No  rock;  mainly  till. 

Sees.  12  and  13,  T.  34,  E.  7  E  . . . 

550 

50 

Mainly  through  sand  and  gravel.    Rock  at  bottom. 

Sees.  21  and  22,  T.  34,  R.  7  E  ... 

575 

45 

Drift  about  45  feet. 

Sees.  7  and  18,  T.  34,  R.  8  E  . . . . 

550 

50 

Mainly  sand;  drift  about  50  feet. 

Sec.  12,  T.  33,  R.  7  E 

510 

60 

Rock  at  bottom.     Wells  in  vicinity  enter  rock  at 

shallower  depth. 

Sec.  23,  T.  33,  R.  6  E 

575 

81 

Till,  30  feet ;  sand,  51  feet. 

Sec.  24,  T.  33,  R.  6  E 

575 
500 

113 

50 

Till,  50  feet ;  sand,  63  feet. 

See.  13,  T.  33,  R.  6  E 

Entirely  sand. 

Till,  18  feet ;  sand,  102  feet. 

Sec  22  T  33.  R.  6  E 

590 

120 

Sec  21  T.  33  R.  6  E 

590 

120 

Till,  40  ieet ;  sand  80  feet. 
Till,  20  feet;  sand  35  feet. 

Sec.34,  T.33,  R.  6E 

600 

55 

Sec.  35,  T.  33,  R.  6  E 

600 

50 

Gravel  below  till  at  bottom. 

WILL  COUNTY. 


GENERAL  STATEMENT. 


Will  County  is  situated  on  the  eastern  border  of  the  State,  immediate!)- 
south  of  Dupage  and  Cook  counties,  and  has  an  area  of  850  square  miles, 
with  Joliet  as  the  county  seat.  Its  northwestern  portion  is  crossed  by  the 
broad  vallej'  of  the  Des  Plaiues,  formerly  the  outlet  of  Lake  Chicago. 
The  extreme  western  part  is  traversed  in  a  southward  course  by  the  Dupage 
River.     Tlic  southwiest  corner  is  crossed  in  a  northwestward  direction  by 


WELLS  OF  WILL  COUNTY,  ILLINOIS.  649 

the  Kankakee,  which  joins  the  Des  Plaines,  just  west  of  the  county  hne, 
to  form  the  lUinois  River. 

The  northwest  part  of  the  county  and  adjacent  portions  of  Dupage 
and  Cook  counties  are  occupied  by  the  Valparaiso  morainic  system  from 
which  drainage  hnes  lead  to  the  southwest  across  a  much  lower  region,  the 
altitude  of  the  crest  being  about  750  to  800  feet,  while  the  plain  south- 
west of  it  stands  but  600  feet  in  average  elevation,  and  scarcely  reaches 
675  feet  where  highest.  The  extreme  western  border  of  the  county  is 
occupied  by  the  Minooka  till  ridge  from  the  north  line  southward  to  the 
head  of  the  Illinois  River. 

Rock  is  extensively  exposed  in  the  southwestern  and  western  parts  of 
the  county,  but  is  seldom  encountered  even  in  wells  in  the  eastern  part. 
The  average  distance  to  rock  in  55  wells  situated  in  the  low  district  outside 
the  Valparaiso  moraine  is  43  feet,  which  probably  represents  the  approxi- 
mate average  for  that  portion  of  the  county.  Forty-two  other  wells,  sitii- 
ated  mainly  along  the  Valparaiso  moraine,  though  having'  an  average  depth 
of  76  feet,  do  not  enter  rock.  The  thickness  in  that  portion  of  the  county 
probably  exceeds  100  feet,  thoug'h  in  places  rock  is  near  the  surface.  Along 
the  valleys  there  are  extensive  gravel  or  sand  deposits  and  the  southwestern 
portion  of  the  county  is  covered  with  sand  dunes.  The  A^alparaiso  moraine 
and  the  plain  southwest  of  it  have  at  surface  till  to  a  depth  of  25  to  50  feet 
or  more,  beneath  which  sand  and  gravel  is  often  found.  The  presence  of 
this  sand  and  gravel  beneath  the  till  renders  this  county  one  especially  well 
favored  for  an  adequate  supply  of  excellent  water  at  shallow  depths.  Very 
few  wells,  aside  from  deep  artesian  wells,  have  been  sunk  to  a  depth  of 
100  feet. 

INDIVIDUAL    WELLS.  , 

The  city  of  Joliet  obtains  its  public  water  supply  from  three  wells 
1,200  feet  and  one  1,700  feet  in  depth.  The  shallower  ones  terminate  in 
the  St.  Peter  sandstone  and  the  deeper  one  probably  in  the  Lower  Magnesian, 
though  it  may  reach  Potsdam  strata.  The  head  is  about  40  feet  above  the 
surface,  or  575  feet  above  tide.  Each  well  has  a  capacity  of  about  500 
gallons  per  minute.  The  water  is  moderately  hard,  but  of  pleasant  taste. 
The  deepest  well  is  cased  only  325  feet  and  its  water  has  a  temperature 
of  45°  F.  Mr.  F.  W.  Dewey,  superintendent  of  waterworks,  reports  that 
the  water  can  be  lowered  b)'  pumping  to  a  depth  of  70  feet  below  the 


650 


THE  ILLINOIS  GLACIAL  LOBE. 


surface,  aiid  tliat  wells  to  a  distance  of  nearly  one-half  mile  are  perceptibly 
lowered  by  heavy  draughts  on  any  one  well.  Many  other  ai-tesian  wells 
are  made  within  the  limits  of  the  city  and  the  rock  strata  are  drained  to 
about  their  fullest  capacity.  A  well  at  the  Joliet  Steel  Mill  reaches  a  depth 
of  2,076  feet,  and  one  at  the  State  Penitentiary  a  depth  of  1,948  feet,  both 
terminating  in  Potsdam  sandstone.  Another  well  at  the  penitentiary  is  but 
553  feet  in  depth  and  obtains  its  supply  probably  from  the  Gralena  limestone. 

Artesian  wells  are  obtained  at  Lockport,  but  no  data  have  been  collected. 
There  are  also  artesian  wells  at  Wilmington  and  Braidwood,  and  an  artesian 
well  has  been  sunk  on  the  farm  of  Judge  Caton,  about  8  miles  west  of 
Joliet.  The  Braidwood  well  was  made  with  a  diamond  drill,  and  the  care- 
fully presei-ved  core  formed  an  interesting  exhibit  at  the  World's  Fair  in 
Chicago,  in  1 893.  The  depth  is  900  feet,  but  the  main  supply  of  water  is 
from  a  porous  sandstone  at  655  to  855  feet,  the  lower  45  feet  being  in  a  lime- 
stone with  green  shale  interbedded.  The  well  formei'ly  ovei-flowed,  but  at 
present  stands  near  the  level  of  the  well  mouth  (588  feet  above  tide).  The 
water  is  slightly  sulphurous,  but  not  of  unpleasant  taste. 

At  Wilmington  the  best  supply  of  artesian  water  is  obtained  at  a  depth 
of  about  600  to  635  feet,  though  in  some  cases  strong  water  veins  are  struck 
at  100  feet  and  several  wells  obtain  water  at  250  to  450  feet.  The  head  at 
these  wells  is  about  the  same  as  at  Braidwood,  slightly  below  600  feet 
above  tide. 

The  following  table  of  wells  on  the  Valparaiso  niorainic  system  includes 
the  deepest  of  which  records  were  obtained.  The  sections  begin  near  the 
State  line  and  proceed  westward  and  northward  across  the  county. 

Wells  oil  the  Valparaiso  morainic  system  in  Will  County. 


Owner  or  loi.'ation. 


Altitncle 


(abovetide).    "'?*''• 


Remarks. 


Feet. 

Between  Goodnow  and  State 

750 

line. 

Endor  and  vicinity 

68.5 

.S  miles  fia.st  of  Crete     -    - 

725 

Crest  of    moraine    smitli    of 

750 

Crete. 

Crete 

720 

Feet. 


100     Several  wells  .50  to  100  feet:  mainly  till;  no  lock 
encountered. 

75      Drift,  mainly  till,  75  feet;  rock  near  bottom. 

40     Rock  entered  at  40  feet. 
130     No  rock  etruok. 


80 


Rock  at  80  feet.     Many  wells  from  sand  at  25  to  40 
feet. 


WELLS  OF  WILL  COUNTY,  ILLINOIS.  651 

Wells  on  the  Valparaiso  niorainic  system  in  Will  County — Continued. 


Owner  or  location. 

Altitude 
(above  tide). 

Depth. 

Remarks. 

Feet. 

Feet. 

Seo.S,  T.  34,  R.  14  E 

T2b 

52 

Till   23  feet-  R.i,Tir1    29  feet 

Mr.  Piepenbrinck,  sec.  11 

725 

106 

Gravel  below  till  at  bottom. 

Sec.  1,  T.  34,  R.  14  E 

725 

77 

No  Toclc  •^tmpt 

C.L.  Pease,  sec.  28 

■  775 

112 

No  rock,  mainly  bine  till. 

Beecher  (east  part) 

720 

106 

No  rock,  mainly  blue  till. 

Old  soil  beneath  glacial  gravel  at  50  feet. 

2  miles  east  of  Beecher 

725 

50 

Monee  antl  vicinity 

800 

50 

Wells  in  sand  below  till  n,t  40  fn  nO  fppt 

One-half  milo  north  of  Monee. 

800 

180 

Mainly  blue  till. 

Sec.  4,  T.  34,  R.  13  E 

775 

70 

Till.  50  feet-  sand   20  feet 

Sec.  10,  T.  34,  R.  13  E 

800 

92 

No  rock,  mainly  blue  till.     Several  wells. 

Sec.  12,  T.  34,  R.  13  E 

750 

65 

Three  wells,  similar:  Till,  55  feet;  sand,  10  feet; 
no  rock. 

Peotoiie  and  vicinity 

725 

60 

Wells,  40  to  60  feet,  mainly  till ;  no  rock. 
Similar  to  preceding. 

North  part  T.  33,  R.  12  E 

675 

60 

Sec.  26,  T.  34,  R.  12  E 

725 

55 

No  rock,  mainly  till. 
No  rock,  mainly  till. 
Drift  exceeds  100  feet  In  several  wells. 

Sec.  36,  T.  34,  R.  12  E 

725 

50 

Morainic  crest,  T.  34,  R.  12  E  . . 

7.50 

100 

Morainic  crest,  T.  35,  R.  12  E  . . 

750 

100 

Wells  through  till ;  no  rock. 

A.  Reid,  sec.  13,  T.  35,  E.  12  E. . 

710 

10 

Rock  entered  at  10  feet. 

Frankfort 

758 

90 

Wells  70  to  90  feet,  mainly  till;  no  rock. 
No  rock  struck. 

Mr.    Baumgartner,     1    mile 

760 

135 

southwest  of  Frankfort. 

Spencer,  at  Elevator 

711 

75 

Mainlv  till  -  sand  at  bottom 

Sec.8,  T.  35,  R.  11  E 

630 

48 

A.^tv.xi   V       vm  ,       .3Cl'iiVX    turn     UUI/UulXl. 

Yellow  till,  15  feet;  sand,  15  feet;  yellow  till,  18 
feet. 

Sec.  18,  T.  35^  R.  11  E 

650 

60 

Cemented  gravel  below  blue  till  near  bottom. 

New  Lenox  and  vicinity 

630 

33 

AVells  in  valley  enter  rock  at  7  to  33  feet. 

Sec.  35,  T.  35,  R.  11  E 

720 

82 

Yellow  clay,  8  feet ;  gravel,  14  feet ;  blue  till,  60  feet. 
Drift,  mainly  till,  95  feet;  limestone,  13  feet. 
No  rock;  mainly  till. 

Sec.9,  T.36,  R.  11  E 

750 

108 

Sec.  12,  T.  36,  R.  HE 

710 

104 

Sec.  12,  T.36,  R.  HE 

720 

114 

No  rock;  mainly  till. 
No  rock;  mainly  till. 
Till,  68  feet;  gravel,  12  feet. 
Till,  50  feet;  sand,  12  feet. 

Sec.  13,  T.  36,  R.  11  E 

700 

115 

Sec.  32,  T.  36,  R.  n  E 

675 

80 

Des  Plaines bluff,  eastof  Romeo 

640 

62 

Sees.  9,  10,  11,  and  12,  T.  37, 

725 

60 

In  cemented  gravel  below  till. 

E.  10  E. 

Sec.  11,  T.  37,  E.  10  E 

700 

96 

No  rock  struck. 

Mr.  Godfrey,  sec.  13 

760 

160 

Till,  100  feet;  gravel,  10  feet;  sand,  40  feet;  lime- 
stone, 10  feet. 

Mr.  Gowdy,  near  Dupage  post- 

650 

50 

Rock  in  one  well  at  35  feet;  none  in  another  at  50 

office. 

feet. 

652 


THE  ILLINOIS  GLAOIAL  LOBE. 


The  following  table  serves  to  illustrate  the  depth  and  character  of 
di-ift  in  the  deep  wells  in  the  portion  of  the  county  outside  the  Valparaiso 
system : 

Welln  in  Will  County  outside  the  Valiiaraiso  morainic  system. 


O^^Tier  or  location. 

Altitude 
(above  tide). 

Depth. 

Remarks. 

Feet. 

Feet. 

West  border  T.  37,  R.  9  E 

T2o 

130 

Wells  on  Minooka  Ridge  penetrate  till  80  feet,  be- 
neath which  is  sand  extending  to  rock  at  about 

130  feet. 

East  half  ofT.37,  E.9E 

650 

20 

AVells  usually  enter  rock  at  about  20  feet;    drift 
gravelly. 

T  35  R  9E                         

620 

30 

Gravelly  drift  between   Dupage  and  Des  Plaines 
River;  wells  at  about  30  feet. 

i  t  t^nj^    ^M.%it   f   -»j  -•■•   .•••«   ----    A***   -to 

County  Infirmary,  T.  35,  R.  9  E. 

620 

40 

Mainly  through  gravel. 

Sec.  36,  T.  35.  R.  9  E 

575 

45 

Till  "with  thin  sand  beds. 

Sec.  7,  T.  34,  R.  10  E 

600 

80 

Flowing  -well,  mainly  till.     Thought  not  to  enter 
rock. 

Sec.  25,  T.  34,  R.  9  E 

630 

60 

Yellow  till,  20  feet;  blue  till,  40  feet;  limestone,  6 
feet. 

Joliet  Mound,    se.'.  19,  T.  35, 

560 

60 

Cobble  and  gravel,  45  feet;  clay,  15  feet;  limestone 

R.  IDE. 

at  Ijottom. 

NE.  corner  T.  3.5,  R.  10  E 

675 

110 

Wells  90  to  110  feet;  mainly  till;  no  rock. 

El  wood  tile  factory 

640 

70 

Till,  with  thin  beds  of  gravel.     Xeighboriug  wells 
enter  rock  at  50  feet. 

Sec.  13,  T.  34,  R.  10  P: 

650 
-       630 

32 

28 

Till  to  rock,  at  32  feet. 

Sec.  14,  T.  34,  R.  10  E 

Drift,  mainly  till;  rock  at  28  feet. 

Sec.  20,  T.  34,  K.  10  E 

630 

75 

Mainly  till;  rock  at  75  feet. 

Sec.  24,  T.  34,  R.  10  E 

630 
650 
650 

38 
32 
58 

Till,  20  feet;  sand,  9  feet;  till  to  rock  (9  feet). 
Till,  17  feet;  sand,  5  feet;  till  to  rock  (10  feet). 
Rook  at  bottom. 

Sec.  26,  T.  34,  R.  10  E 

Sec.  32,  T.  34,  R.  10  E 

Sec.  34,  T.  34,  R.  10  E 

660 

35 

Mainly  till;  rock  at  bottom. 

Sec.  21,  T.  33,  R.  10  E 

600 
640 

90 
50 

Drift,  mainly  till,  49  feet;  limestone.  41  feet. 

Sec.  6,  T.  33,  R.  10  E 

Mainly  till;  rock  at  bottom. 

Yellow  till,  12  feet;  blue  till,  40  feet;  no  rock. 

Sec.  16,  T.  33,  R.  10  E 

660 

52 

Sec.  34,  T.  .S3,  K.  9  E 

560 

31 

Till,  13  feet;  sand,  18  feet. 

Wilmington  ;ind  vicinity 

560 

40 

AVells  20  to  40  feet,  from  gravel. 

Braidwood 

1            590 

40 

Wells  18  to  40  feet;  sand,  15  or  20  feet;  blue  clay, 
20  or  25  feet. 

2  miles  east  of  Braidwood 

590 

220 

Sand,  20  feet;  blue  clay,  20  feet;  remainder  rock, 

180  feet. 

1 

WELLS  OF  KANKAKEE  COUNTY,  ILLINOIS.  653 

KANKAKEE    COUNTY. 
GENERAL   STATEMENT. 

This  county  is  situated  on  the  eastern /border  of  the  State  immediately 
south  of  Will  County,  and  has  an  area  of  680  square  miles,  with  Kankakee 
as  the  county  seat.  The  Kankakee  River  leads  westward  tlu-ough  its  cen- 
tral portion.  The  greater  portion  of  the  county  is  imperfectly  drained, 
there  being-  extensive  marshes  and  sandy  areas  in  the  southeastern  part,  and 
a  very  level  surface  in  the  western,  while  the  northern  portion  is  character- 
ized by  occasional  sloughs  and  marshes. 

The  drift  is  a  comparatively  thin  deposit  along  the  Kankakee  River 
and  its  borders  tln-oughout  the  county,  but  the  western,  southern,  and 
northeastern  portions  of  the  county  have  a  sheet  of  drift  probably  not  less 
than  100  feet  in  average  thickness.  In  the  vicinity  of  the  Kankakee  the 
drift  consists  mainly  of  gravel  or  sand,  but  in  its  thicker  portions  on  the 
borders  of  the  county  there  is  generally  present  a  heavy  sheet  of  till. 

The  wells  are  of  moderate  depth  throughout  the  county,  there  being- 
very  few  which  reach  100  feet,  even  in  the  portions  where  it  is  necessary 
to  di'ill  into  rock. 

INDIVIDUAL    WELLS. 

The  public  water  supply  for  the  city  of  Kankakee  is  pumped  from 
the  Kankakee  River,  but  there  are  numerous  drilled  wells  in  the  city  30  to 
90  feet  in  depth.  A  small  till  ridge  leading  eastward  from  the  vicinity  of 
the  court-house  aifords  water  at  depths  of  20  to  60  feet  without  entering 
rock.  Throughout  much  of  the  city,  however,  rock  is  found  at  a  depth  of 
10  feet  or  less. 

A  well  sunk  on  the  south  side  of  the  Kankakee  opposite  the  city 
reached  a  depth  of  1,000  feet,  entering-  St.  Peter  sandstone  at  900  feet. 
The  water  rises  within  15  feet  of  the  surface,  or  to  about  605  feet  above  tide. 

At  Momence  the  wells  are  obtained  in  limestone  at  a  depth  of  12  to  80 
feet.  A  strong  well  can  usually  be  obtained  at  a  depth  of  30  feet.  The 
wells  are  generally  about  5  inches  in  diameter  and  are  reported  to  be 
practically  inexhaustible. 

In  the  southeast  township  of  the  county  several  flowing  wells  have 
been  obtained  from  sand  below  a  gray  clay  at  depths  ranging  from  30  to 


654  THE  ILLINOIS  GLACIAL  LOBE. 

90  feet.     In  some  cases  water  fails  to  reach  the  surface,  choug-h  all  the  wells 
m  that  locality  have  strong  hydrostatic  pressure. 

At  St.  Anue  a  few  of  the  wells  reach  a  depth  of  80  feet,  entering  rock 
at  about  60  feet. 

At  Sherburnville,  on  the  east  border  of  the  countv,  wells  frequently 
reach  a  depth  of  60  feet  without  entering  rock.  They  peneti-ate  25  or  30 
feet  of  till,  beneath  which  is  sand.  Much  of  T.  32,  R.  14  E.,  which  is  situ- 
ated west  from  Sherburn^^lle,  has  wells  of  similar  depth  and  structui-e,  but 
in  the  northeast  part  of  T.  32,  R.  13  E.,  rock  is  often  struck  at  a  dei^th  of 
30  or  40  feet. 

In  the  vicinity  of  St.  George,  in  the  northern  part  of  the  countv,  wells 
usually  enter  rock  at  a  depth  of  10  or  20  feet.  This  thin  drift  characterizes 
much  of  northern  Kankakee  County  westward  beyond  Manteno. 

In  a  few  places  in  the  west  part  of  T.  32,  R.  14  E.,  and  in  T.  32,  R. 
13  E.,  well  di-iUers  repoi't  having  passed  tlu-ough  an  old  soil  below  the  blue 
till  near  the  base  of  the  drift. 

At  Deselm  post-office,  in  the  northwest  part  of  the  counts',  there  is  a 
drift  ridge  in  which  the  distance  to  rock  is  about  60  feet,  the  level  being 
about  the  same  beneath  the  ridge  as  on  the  bordering  plain.  In  the  south- 
west part  of  the  county  on  the  border  of  the  Marseilles  moraine  records  of 
6  wells  were  obtained  which  reach  rock  at  a  depth  of  100  to  162  feet.  The 
altitude  is  about  700  feet  above  tide,  or  nearly  100  feet  above  the  Kanka- 
kee River  at  the  city  of  Kankakee.  The  rock  surface  is  therefore  not  much 
lower  than  at  Kankakee.  In  the  vicinity  of  Irwin  and  Dickev  and  Her- 
sher  rock  is  usually  entered  at  40  to  60  feet,  but  at  Buckingham  the  drift 
is  about  90  feet  in  depth.  Two  flowing  wells  have  been  obtained  at  Dickey 
from  beds  of  gravel  and  sand  at  the  base  of  the  di-ift.  The  underlying  rock 
is  shale. 

From  Union  Hill  eastward  to  Kankakee  the  drift  is  generally  of  slight 
depth,  but  from  this  village  westward  to  the  county  line  its  tliickuess  is  50 
to  100  feet  or  more. 

IROQUOIS    COUNTY. 
GENERAL,   STATEJIENT. 

Iroquois  Count}-  is  situated  south  of  Kankakee  ou  the  east  border  of 
the  State,  and  has  an  area  of  1,120  square  miles,  being  exceeded  in  size 


WELLS  OF  IROQUOIS  COUNTY,  ILLINOIS.  655 

oiily  by  McLean  and  Lasalle  counties.  Watseka,  the  county  seat,  is  sit- 
uated a  few  miles  east  of  tlie  g-eog-vapliic  center.  The  Iroquois  River  enters 
the  county  from  Indiana  in  the  northeast  part,  and  after  "passing  westward 
to  Watseka  it  turns  northward  and  enters  the  Kankakee  a  short  distance 
north  of  the  county  Hne.  This  stream,  with  its  tributaries,  drains  almost 
the  entire  county.  It  is  a  widely-branching  drainage  system,  yet  the  num- 
ber of  di'ainage  lines  is  too  few  to  afford  escape  for  the  surplus  rainfall,  and 
there  are  extensive  marshes  within  its  drainage  basin. 

The  county  is  mostly  occupied  by  a  basin  whose  borders  lie  not  far 
beyond  the  county  limits.  On  the  west  and  south  this  basin  is  limited  by 
the  prominent  Bloomington  morainic  system;  on  the  north  the  basin  is 
limited  by  the  Marseilles  moraine,  which  follows  nearly  the  line  of  Iroquois 
and  Kankakee  counties;  on  the  east  it  finds  a  natural  limit  in  the  Iroquois 
moraine,  which  traverses  the  eastern  portion  of  the  county.  This  basin  is 
due  entirely  to  di-ift  aggregation,  for  the  underlying  rock  apparently  stands 
higher  in  the  low  part  of  the  basin  in  the  northern  portion  of  the  county 
than  in  the  rim  of  the  basin  on  the  west  and  south. 

This  basin  is  found  to  be  a  favorable  locality  for  obtaining  flowing- 
wells  from  the  di'ift,  and  several  hundred  have  already  been  made,  which 
have  been  discussed  by  the  writer  in  the  Seventeenth  Annual  Rejjort  of  this 
Survey.  There  is  a  perceptible  increase  of  head  in  passing  from  north  to 
south.  There  is  an  increase  also  in  passing  from  near  Watseka  either  east- 
ward or  westward.  There  is  little  doubt,  therefore,  that  the  absorbing- 
areas  are  found  on  the  east,  south,  and  west  borders  of  the  basin.  This  is 
contrary  to  the  interpretation  made  by  the  residents,  who  quite  generally 
suppose  the  supply  to  be  derived  from  the  Kankakee  marsh  on  the  north- 
east, a  marsh  whose  altitude  is  in  the  main  below  the  level  of  the  lawer 
parts  of  this  basin. 

The  drift  is  largely  a  soft  till  to  a  depth  of  76  or  100  feet,  though  in 
the  northeastern  part  of  the  county  there  is  a  surface  sand  a  few  feet  in 
depth  capping  the  till  and  which  connects  with  the  sand  of  Kankakee 
County  mentioned  above.  The  till  is  found  to  be  underlain  at  many  points 
hj  a  black  soil  and  by  beds  of  peat  and  shell  marl.  With  the  peat  and 
marl  there  is  usually  considerable  sand,  which  is  a  source  for  the  flowing 
wells.  After  these  beds  of  peat  and  sand  are  jjenetrated  a  harder  till  is 
entered  than  the  surface  sheet.     In  some  cases  this  till  is  found  to  include 


656  THE  ILLINOIS  GLACIAL  LOBE. 

beds  of  peaty  soil  and  sand  which  afford  water  for  the  flowing-  wells.  In 
one  case,  near  the  south  border  of  the  countv,  a  buried  peat  was  found  to 
have  a  depth  of  30  feet,  showing  that  a  long  interval  must  have  elapsed 
between  the  deposition  of  the  sheets  of  drift  which  it  separates.  The  time 
•  need  be  no  longer  than  has  elapsed  since  the  upper  till  sheet  was  deposited, 
for  in  that  same  locality  there  is  an  instance  of  the  penetration  of  peat  to  a 
depth  of  32  feet;  there  being  a  kettle-hole  with  an  area  of  5  acres  which 
has  peat  of  this  thickness,  as  shown  by  a  series  of  test  borings  made  bv  Dr. 
Luddeu,  of  East  Lynn.  The  thick  deposit  of  bui'ied  peat  just  refen-ed  to 
occurs  in  the  midst  of  the  hard  tills  and  not  at  the  junction  of  the  soft  till 
with  the  hard  till,  there  being  26  feet  of  hard  brown  till  above  the  peat, 
which  in  tui-n  is  overlain  by  80  feet  of  soft  till  of  the  Wisconsin  stage. 

INDITIDUAJL   WELLS. 

At  St.  Mary's,  in  the  northeast  pait  of  the  county,  wells  are  usually 
obtained  at  about  40  feet.  One  well  in  the  village,  however,  was  sunk  to  a 
depth  of  140  feet  without  entering  rock  ;  it  passed  thi-ough  an  old  soil  at  80 
feet,  and  water  from  the  lower  portion  of  the  well  rose  within  18  feet  of  the 
surface.  Thi'ee  wells  about  a  mile  west  of  St.  Mary's,  at  an  altitude  perhaps 
20  feet  lower,  enter  rock  at  90  to  100  feet.  The  di-ift  is  mainly  till,  and 
water  rises  within  20  feet  of  the  sui-face,  or  to  about  630  feet  above  tide. 
East  from  St.  Marv's  several  wells  enter  rock  at  about  100  feet,  thoug-h 
occasionallv  a  greater  amount  of  drift  is  penetrated.  For  instance,  in  sec. 
11,  T.  28,  R.  11  W.,  a  well  176  feet  in  depth  enters  rock  at  135  feet.  The 
di'ift  is  mainly  blue  till.  Water  rises  from  the  rock  to  within  15  feet  of  the 
surface. 

At  the  village  of  Papineau  wells  enter  rock  at  40  to  45  feet  and  water 
rises  within  5  feet  of  the  smiace.  In  the  valley  of  Beaver  Creek,  north  of 
tliis  village,  at  an  elevation  about  15  feet  lower,  several  flowing  wells  have 
been  obtained,  some  being  from  the  drift,  others  from  the  rock. 

In  the  vicinity  of  Martinton  rock  is  entered  at  about  60  feet.  A  well 
1  mile  north  of  this  village,  276  feet  in  depth,  penetrates  drift,  raainlv  till, 
60  or  65  feet;  shale,  15  feet;  mainly  limestone,  196  feet.  The  water  level 
is  10  feet  below  the  surface,  or  620  feet  above  tide. 

At  Pittwood  several  weUs  have  been  sunk  to  a  depth  of  100  to  130 


WELLS  OF  IROQUOIS  COUNTY,  ILLINOIS.  657 

feet  without  reaching  rock.  Wood  is  found  occasionally  near  the  bottom. 
Water  rises  within  15  feet  of  surface  or  to  about  630  feet  above  tide.  Three 
miles  northwest  of  this  village,  in  sec.  26,  T.  28,  R.  13  W.,  a  well  penetrates 
till  sheets  of  different  hardness.  The  iipper  45  feet  is  a  soft  till,  the 
remainder  a  hard  till.  The  bed  of  sand  at  bottom  furnishes  water  which 
rises  within  3  feet  of  the  surface.  In  the  adjoining  section  on  the  south 
(sec.  35)  a  well  156  feet  in  depth  does  not  reach  rock.  Water  rises  just  to 
the  surface.  In  sec.  29  of  this  township  a  well  penetrated  an  old  soil  near 
the  base  of  the  drift  at  a  depth  of  about  95  feet.  Wells  in  that  vicinity 
enter  shale  at  about  100  feet  and  limestone  at  about  160  feet. 

In  the  north  part  of  the  county,  near  Chebanse,  rock  is  entered  at  80  to 
100  feet.  About  3  miles  east  of  the  village  on  the  farm  of  0.  Sykes,  and 
also  on  neighboring  farms,  wells  were  noted  in  which  beds  of  peat  20  feet 
in  thickness  were  found  near  the  base  of  the  drift  at  depths  of  60  to  80  feet. 

In  the  vicinity  of  Ashkum  wells  usually  enter  rock  at  about  80  feet, 
though  one  half  a  mile  west  of  the  village  reached  a  depth  of  146  feet 
before  striking  rock.  There  is  usually  a  soft  till  about  50  feet,  beneath 
which  is  a  harder  till,  associated  in  places  with  sand  beds.  The  water  level 
from  wells  obtained  in  the  lower  part  of  the  drift  and  upper  part  of  the  rock 
is  10  to  20  feet  below  the  surface,  or  about  640  feet  above  tide.  Along  the 
border  of  Langum  Creek  Valley,  in  the  vicinity  of  Ashkum,  wells  enter 
limestone  at  60  to  90  feet.  In  some  cases  they  obtain  water  in  sand  below 
till  at  40  to  60  feet.  The  water  usually  rises  within  5  or  10  feet  of  the 
surface.  A  well  at  Mr.  Mayo's,  about  5  miles  northwest  of  Ashkum,  pene- 
trated 120  feet  of  drift  containing  a  log  near  the  bottom,  and  terminated  in 
shale  at  167  feet.  Water  stands  within  4  feet  of  the  sui-face,  the  altitude 
being  slightly  lower  than  at  Ashkum.  About  3  miles  west  from  this  well 
the  records  of  three  wells  were  obtained  which  obtain  water  in  limestone 
at  60  to  68  feet.  The  head  is  sufficient  to  bring  the  water  barely  to  the 
surface. 

In  the  vicinity  of  Prairie  Creek,  southeast  from  Ashkum,  a  few  flowing 
wells  have  been  obtained'from  the  drift  at  depths  of  75  feet  or  less. 

At  Danforth  wells  from  the  drift  100  feet  in  depth  have  a  head  about 
7  feet  below  the  surface  or  about  640  feet  above  tide.     The  last  edition  of 
the  Manual  of  American  Waterworks  reports  a  deep  well  in  progress,  but 
MON  xxxviu 42 


658  THE  ILLINOIS  GLACIAL  LOBE. 

no  good  supply  had  been  obtained  though  sunk  to  a  depth  of  1,200  feet. 
Near  this  village,  at  Mr.  Eden's,  a  well  168  feet  in  depth  peneti-ates — 

•  Section  of  Eden  well  near  Danforth,  Illinois. 

Feet. 

Soft  till 70 

Hard  till 60 

Shale 38 

It  obtains  water  in  limestone  at  bottom.  A  neighboring  well  obtains 
water  at  72  feet,  in  sand  below  a  soft  till.  Wood  was  found  just  above  the 
water  vein. 

At  La  Hogue  several  flowing  wells  have  been  obtained  from  the  drift 
at  depths  of  70  or  80  feet.  They  are  mainly  throiigh  soft  blue  till. 
Flowing  wells  are  found  at  a  similar  depth  at  Ridgeville  and  in  the  interval 
between  these  two  villages.  Occasionally  a  well  only  40  or  45  feet  in  depth 
has  sufficient  head  to  nearly  reach  the  surface. 

At  Gilman  flowing  wells  are  obtained  from  the  drift  at  depths  of  75  to 
150  feet.  It  is  designed  to  use  such  wells  for  a  p^^blic  water  supply. 
Occasionally  wells  are  sunk  to  the  imderlying  rock,  which  is  reached  at 
190  or  200  feet.     The  shallow  wells  in  Oilman  are  obtained  at  12  to  16  feet. 

At  Onarga  several  wells  have  been  sunk  to  a  depth  of  90  to  160  feet 
from  which  water  rises  within  10  or  15  feet  of  the  surface,  or  to  about  660 
feet  above  tide.  The  public  supply  is  from  three  wells  of  this  class.^  In 
a  portion  of  this  village  there  is  sm-face  sand  to  a  depth  of  12  to  18  feet, 
at  the  bottom  of  which  wells  are  often  obtained.  The  following  three  bor- 
ings are  reported  in  the  geology  of  Illinois.  A  coal  boring  near  Onarga  is 
thought  to  have  reached  a  depth  of  400  feet  without  encountering  rock, 
though  it  terminated  at  an  elevation  but  260  feet  above  tide,  or  about  the 
level  of  the  Mississippi  River  at  Cairo.  The  reliability  of  this  record 
appears  questionable,  it  being  given  from  memory  some  years  after  the 
boring  was  made.  A  boring  between  Onarga  and  Oilman  is  reported  to 
have  reached  rock,  thought  to  be  Lockport  (Niagara)  limestone,  at  268  feet, 
the  drift  section  being  as  follows : 

Section  of  a  horinq  betioeen  Onarga  and  Gilman,  Illinois. 

Feet. 

Blue  and  red  clay 98 

Sand  and  soft  sediment 1*0 

Hardpan ^0 

Hard  stony  clay -^0 

Total 268 

'  Manual  of  American  Waterworks,  1897. 


WELLS  OP  lEOQUOIS  COUNTY,  ILLINOIS.  659 

At  Onarga  a  coal  boring  readied  the  first  rock  at  about  300  feet.  The 
rock  was  interpreted  to  be  Hudson  River  (Cincinnati)  shale.^ 

In  the  vicinity  of  Crescent  many  flowing  wells  have  been  obtained  at 
depths  of  80  to  120  feet.  There  is  scarcely  a  section  in  the  south  half  of 
T.  27,  R.  13  W.,  or  any  part  of  T.  26,  R.  13  W.,  in  which  the  water  does 
not  overflow  or  rise  within  10  feet  of  the  surface.  The  public  water  supply 
at  Crescent  is  from  four  wells  of  this  class.^  Many  wells  south  of  Crescent 
pass  thi'ough  an  old  soil  at  depths  varying  in  the  different  wells  from  60  to 
80  feet  below  the  surface.  Above  the  soil  the  till  is  not  nearly  so  hard  as 
that  below. 

At  Watseka  many  flowing  wells  have  been  obtained  from  the  drift  at 
depths  of  100  to  150  feet,  and  the  first  rock  is  encountered  at  about  165 
feet.  The  public  water  supply  is  from  a  well  150  feet  in  depth,  which  has 
sufficient  capacity  to  supply  the  city.  In  the  higher  portions  of  the  city 
the  water  falls  short  a  few  feet  of  reaching  the  surface.  The  mayor  reports 
that  no  shallow  wells  are  in  use  and  that  few  wells  are  obtained  at  less 
depth  than  85  feet.  The  surface  is  coated  to  a  depth  of  a  few  feet  with 
sand,  beneath  which  there  is  a  soft  blue  till  extending  to  a  depth  of  85  or 
100  feet.     Beneath  this  a  hard  till  with  alternating  sand  beds  is  penetrated. 

Along  the  Iroquois  Valley  above  Watseka  in  this  county,  and  also  in 
Newton  County,  Indiana,  flowing  wells  are  obtained  from  the  drift  at  depths 
of  70  to  120  feet.  A  well  at  the  village  of  Iroquois,  88  feet  in  depth,  is 
reported  to  have  passed  through  a  black  soil  below  blue  till  near  the  bottom. 

North  of  the  Iroquois  Valley,  on  the  Iroquois  moraine,  in  the  vicinity 
of  Donovan,  several  deep  borings  have  been  made  which  enter  rock  at  depths 
of  125  to  170  feet  and  obtain  their  supply  from  limestone  at  200  feet  or 
less.  The  water  in  that  locality  rises  within  about  40  feet  of  the  surface, 
or  635  feet  above  tide,  which  is  nearly  the  altitude  in  neighboring  lower 
districts  to  the  north  and  west.  These  deep  wells  in  several  instances 
encounter  an  old  soil  at  about  140  feet.  Hard  till  sets  in  at  about  100  feet- 
No  instance  of  the  occurrence  of  a  soil  at  the  top  of  the  hard  till  was 
reported,  though  it  is  often  present  in  the  neighboring  districts,  as  already 
noted. 

Soiith  of  the  Iroquois  River,  in  the  vicinity  of  Sheldon,  the  drift  has 
a  thickness  of  100  to  120  feet  and  is  mainly  a  blue  till.     On  the  moraine 

'Geol.  of  niinois,  Vol.  IV,  pp.  237-238.  ^^jiauual  of  American  Waterworks,  1897. 


660  THE  ILLINOIS  GLACIAL  LOBE. 

south  of  this  village,  iu  sec.  11,  T.  26,  R.  12  W.,  a  well  156  feet  in  depth 
entered  rock  uear  the  bottom  and  struck  a  bed  of  coal.  Two  other  borings 
located  in  the  north  part  of  T.  25,  R.  11  W.,  enter  rock  and  strike  coal  at 
only*  60  feet.  Several  other  wells  in  that  locality  reach  a  depth  of  160  feet 
without  entering  rock.  They  penetrate  about  80  feet  of  soft  till,  beneath 
which  is  a  hard  till,  in  which  little  sand  is  found  at  less  than  160  feet  from 
the  sui'face. 

Along  Sugar  Creek  Valley,  north  of  Milford,  thi-ee  wells  were  noted 
which  strike  an  inflammable  gas  in  sand  below  till  at  a  depth  of  40  feet.  In 
the  vicinity  of  Milford  wells  are  usually  obtained  at  depths  of  40  to  60  feet, 
and  water  does  not  rise  usually  within  less  than  25  feet  of  the  surface,  or  to 
about  645  feet  above  tide.  The  public  supply  is  from  two  8-inch  wells  60 
feet  deep.^     A  boring  at  Milford  in  search  of  coal  has  the  following  section : 

Section  of  a  coal  boring  at  Milford,  Illinois. 

Feet. 

Soft  till 45  to  50 

Hard  till,  with  some  sand  beds 70 

Shale 88 

Limestone  at  bottom 0 

Total -- 208 

West  from  Milford,  for  6  or  8  miles,  several  wells  have  been  sunk  to 
depths  of  100  to  110  feet,  which  obtain  water  in  sand  below  the  blue  till. 
Its  head  is  20  feet  or  more  below  the  surface. 

In  the  southeast  part  of  Iroquois  County  a  black  soil  has  been  found 
in  a  few  wells  at  about  160  feet.  These  wells  penetrate  90  or  100  feet  of 
soft  till  and  50  feet  or  more  of  hard  till  before  entering  the  soil. 

At  Wellington,  wells  are  often  obtained  at  a  depth  of  70  feet,  which 
have  a  head  about  20  feet  below  the  surface,  or  680  feet  above  tide.  They 
are  said  to  enter  a  hard  till  in  the  lower  10  or  15  feet. 

At  Clayton  flowing  wells  are  obtained  at  a  depth  of  60  or  70  feet  and 
also  at  about  100  feet.  The  deeper  ones  penetrate  an  old  soil  near  the 
bottom.  The  head  at  these  wells  is  about  675  feet  above  tide.  Four  miles 
south  of  Clayton,  in  sec.  27,  T.  24,  R.  13  W.,  two  flowing  wells  have  been 
obtained,  one  at  50  feet,  the  other  at  80  feet,  whose  head  is  nearly  700  feet 
above  tide.     A  mile  farther  south  is  the  well  noted  above,  Avhich  penetrated 

'  Manual  of  American  Wiiterworks,  1897. 


WELLS  OF  lEOQfTOIS  COUNTY,  ILLINOIS.  G(3l 

a  buried  peat  30  feet  in  thickness.     It  is  on  the  farm  of  Dr.  Ludden,  in  sec. 
33,  T.  24,  R.  13  W.     The  following  is  the  section  furnished  by  Dr.  Ludden: 

Section  of  Ludden  well,  ~>  mile.i  south  of  Clayton,  Illinois. 

Feet. 

Mainly  blue  till 80 

Hard  brown  till 25 

Peat : 30 

Coarse  sand 9 

Total 144 

At  Cissna  Park  the  public  water  supply  is  from  a  flowing  well,  the 
water  being  pumped  from  the  receiving  reservoir  to  the  standpipe.^ 

North  from  Clayton,  in  the  vicinity  of  Ash  Grove,  many  flowing  wells 
are  obtained  at  a  depth  of  about  100  feet.  They  penetrate  alternations  of 
sand  and  soft  blue  till  to  a  depth  of  55  or  60  feet,  below  which  a  hard  gray 
till  is  entered  with  which  thin  beds  of  gravel,  yielding  water,  are  associated. 
Several  wells  are  reported  to  pass  through  a  soil  containing  wood  at  a  depth 
of  about  100  feet,  or  some  distance  below  the  top  of  the  hard  till.  In  the 
Ash  Grove  timber  belt  wells  are  occasionally  sunk  to  a  depth  of  160  feet 
and  penetrate  a  section  similar  to  the  preceding,  passing  through  soil  and 
wood  at  95  or  100  feet,  beneath  which  are  alternations  of  hard  till  and  sand. 
Occasionally  a  well  passes  through  a  heavy  deposit  of  gravel  or  sand 
beneath  the  soft  till,  but  usually  the  sand  and  gravel  beds  are  thin. 

In  a  low  tract  known  as  Shavetail  Slough,  in  the  northeast  part  of 
T.  25,  R.  13  W.,  several  wells  have  been  sunk  to  a  depth  of  about  160  feet, 
which  penetrate  a  black  soil  below  hard  till  at  160  to  158  feet,  and  obtain 
water  in  sand  at  bottom.     The  head  is  sufficient  to  barely  reach  the  surface. 

In  the  vicinity  of  Buckley,  and  thence  southeast  to  Cissna  Park,  flow- 
ing wells  are  frequently  obtained  at  depths  of  but  50  feet,  in  sand  or  gravel 
below  a  soft  blue  till.  At  Buckley  the  water  rises  within  8  to  16  feet  of  the 
top,  but  on  low  ground  west  of  the  village  a  few  wells  overflow  at  an  alti- 
tude about  690  feet  above  tide.     The  public  supply  is  from  a  flowing  well.^ 

In  the  vicinity  of  Thawville  flowing  wells  are  obtained  only  on  the 
lowest  ground  at  an  altitude  about  685  feet  above  tide.  They  frequently 
reach  a  depth  of  135  or  140  feet,  and  pass  through  a  black  soil  containing 
wood  near  the  bottom. 

'  Mann  al  of  American  Waterworks,  1897. 


662  THE  ILLINOIS  GLACIAL  LOBE. 

In  the  -sdcinity  of  Loda  wells  are  often  sunk  to  a  depth  of  100  feet, 
mainly  through  till.  The  water  rises  as  in  the  flowing  well  district,  but  the 
altitude  is  much  too  high  for  an  overflow,  being  about  775  feet  above  tide. 

FORD    COUNTY. 
GENERAL   STATEMENT. 

Ford  County  is  situated  west  of  Iroquois  and  also  extends  a  short 
distance  along-  the  western  portion  of  the  south  border  of  that  county.  It 
is  a  naiTow  tract,  its  northern  two-thnds  being  but  6  miles  in  width.  It  has 
an  area  of  490  square  miles  and  Paxton  is  the  county  seat.  It  occupies  a 
comparatively  elevated  tract  from  which  streams  discharge  in  all  directions. 
From  the  northern  portion  the  drainage  is  in  part  tributary  to  Mazon  Creek, 
which  enters  the  Illuiois  at  Morris ;  ia  part  to  the  Illinois- Vermilion  River, 
which  enters  the  Illinois  at  Lasalle,  and  in  part  to  the  Iroquois  River. 
The  southern  portion  divides  its  waters  between  the  Iroquois,  the  Wabash- 
Vermilion,  and  the  Sangamon  rivers. 

The  southern  half  of  the  county  is  occupied  by  the  Bloomington 
morainic  system,  whose  highest  points  have  an  altitude  about  860  feet 
above  tide.  The  exti-eme  northern  end  is  occupied  by  the  Marseilles 
system.  Between  these  morainic  systems  there  is  a  plane  tract  which 
constitutes  the  westward  extension  of  the  basin  of  Iroquois  County,  and 
like  it  is  favorably  situated  for  obtaining  flowing  wells.  Its  altitude  is 
650  to  700  feet. 

The  entire  county  is  covered  with  a  nearly  continuous  sheet  of  blue 
till  100  feet  or  more  in  average  depth,  beneath  which  there  is  apparently  a 
series  of  hard  till  deposits  interbedded  with  sand  and  gravel,  similar  to  those 
in  Iroquois  County  ah-eady  discussed. 

Records  of  eight  wells  which  reach  the  rock  show  an  average  thickness 
of  211  feet  of  drift,  which  is  perhaps  a  fair  approximation  to  the  average  for 
the  county.  Many  deep  tubular  wells  have  been  sunk  in  this  county,  some 
of  them  reaching  depths  of  over  200  feet  without  entering  rock.  The 
gi-eatest  thickness  reported  within  the  county  is  at  the  artesian  well  in 
Paxton,  where  440  feet  of  drift  was  penetrated. 

INDIVIDUAL   WELLS. 

The  public  water  supply  at  Paxton  is  from  wells  about  150  feet  in 
depth,  obtained  in  sand  and  gravel  below  a  sheet  of  till.     The  water  rises 


WELLS  OF  FORD  (JOUNTY,  ILLINOIS. 


663 


about  100  feet  and  is  practically  inexhaustible.  The  artesian  well  at  this 
city,  referred  to  above,  has  a  depth  of  2,670  feet,  but  no  further  data  con- 
cerning it  have  been  obtained. 

At  Gribson  the  public  water  supply  is  obtained  from  three  wells  55  feet 
in  depth  and  7  inches  in  diameter.  Many  private  wells  are  obtained  at 
12  to  25  feet,  thoug-h  a  few  are  46  to  55  feet.  They  are  largely  through 
sand  and  gravel,  the  town  being  situated  on  a  plain  just  outside  the  Bloom- 
ington  morainic  system,  which  apparently  received  a  coating  of  sand  and 
gravel  as  a  morainic  outwash.  A  boring  for  coal  at  this  city  was  sunk  to  a 
depth  of  705  feet  and  penetrated  175  feet  of  drift. 

The  following  table  of  sections  of  deep  wells  is  begun  at  the  northern 
end  of  the  county  and  proceeds  southwai'd.  It  includes  the  deepest  of 
which  records  were  obtained: 

Deep  wells  in  Ford  County. 


Owner  or  location. 

Altitude 
(above  tide). 

Depth. 

Remarks. 

Feet. 
706 
706 

737 

737 
750 
700 
680 
650 
650 
650 
650 
678 

650 
650 

Feet. 
240 
200 

176 

185 

196 

203 

75 

75 

23 

20 

65 

95 
165 

Depth  given  by  Man.  Amer.  Waterworks,  1897. 
Thin  beds  of  shale  and  coal  overlying  limestone, 

entered  at  about  200  feet,  at  base  of  drift. 
Reported  in  Manual  of  American  Waterworks  that 

public  water  supply  is  from  a  well. 
Drift  mainly  till;  rock  at  about  175  feet. 
Rock  struck  at  bottom ;  drift  mainly  till. 
Enters  rock  at  bottom 

Kempton,  village  well 

Kempton,  several  wells 

Sec.  33,  T.  29,  E.  9  E 

Sec  24  T  29  R.  9  E         

Sec.  11,  T.  28,  R.  9  E 

Vermilion  S"wanit) ...... 

Drift,  150  feet ;  shale  with  two  coal  beds,  53  feet. 
Flowing  wells  from  sand  below  till. 
Flowing  wells  from  sand  below  till 

Sec  5  T.  27,  R.  9  E 

Sec  9  T.26,  R.  9  E 

Three  flowing  wells  20  to  23  feet  in  depth. 
Several  flowing  wells  from  drift  at  about  20  feet. 
Flowing  wells  at  about  65  feet;   five  water  reins 
penetrated;  in  sand  between  tills. 

Sees.  10, 13,  and  14,T.  26,  E.  9  E. 

Sec.  22,  T.  27,  R.  9  E 

Sec  17.T.27.  R.  9E 

feet;  soft  blue  till,  30  or  40  feet;  hard  blue  till, 
25  or  30  feet;    black  muck,  20  feet;    sand   and 
gravel  at  bottom. 
Harder  till  in  lower  than  in  upper  half;   limestone 
near  bottom. 

East  part  Ts.  26  and  27,  R.  9  E . 

(          675 
1          700 

60 
80 

Several  flowing  wells  at  60  to  80  feet. 

Sec.  31,  T.  26,  E.  9  E    

800 

240 

Soft  till,  130  feet;  harder  sandv  drift   110  feet;  no 

rock. 

664 


THE  ILLINOIS  GLACIAL  LOBE. 

I>eep  icells  in  Ford  County — Ooutiiiued. 


Owner  or  location. 


Altitude 
(above  tide) . 


Depth. 


Remarks. 


Sec.  7,  T.  25,  R.  9  E  . 
Sec.7,'T.25,  R.9E  , 


Roberts  No.  1 . 
Roberts  No.2- 


Seo.  25,  T.  25,  E.  8  E  . 


li  miles  southeast  of  Sibley. . 

Melvin 

Sec.  2,  T.  24,  R.9E 

Sec.  11,T.24,  R.  9E 


Sec.  36,  T.  24,  R.  9E 

Northwest  part  T.  24,  R.  9  E . . . 

Near  Henderson  Station 

Seo.28,T.23,  R.  10  E 

Tile  factory  in  Ten-Mile  Grove. 


Paxton  and  vicinity. 


Kirk  Station 

Between  Paxton  and  Kirk... 

Sec.  29,  T.  23,  R.  14  W 


Feet. 


800 
800 


780 
780 

800 


775 

761 
775 

750 


Feet. 
237 

196 


200 
117 

240 


825 

240 

808 

140 

775 

200 

775 

201 

800 

115 

750 

117 

775 

80 

750 

155 

750 

73 

150 

140 
175 

116 


Soft  till,  1  Ofeet;  sand,  20  feet;  blue  clay,  20  feet; 

cemented  sand  and  gravel  at  bottom. 
Yellow  till,  8  feet;    sand  and  gravel,  40  feet;    blue 

till  with  thin  sand  beds,  95  feet;   reddish  till,  10 

feet;  brown  till, 26  feet;  sand  at  bottom,  10  feet. 
No  rock ;  log  at  about  100  feet. 
Blue  till,  91  feet;    hard  gray  till,  24  feet;   sand  at 

bottom. 
Mainly  blue  till,  125  feet ;  black  sand,  6  or  8  feet ; 

blue  till,  80  or  85  feet;  sand,  20  feet. 
No  rock  or  water;  mainly  blue  till. 
Wells  115  to  140  feet;  hard  till  near  bottom. 
Till,  120  feet;  sand,  80  feet. 
Yellow  till,  16  or  18  feet;  blue  till,  70  or  75  feet; 

blue  sand,  85  feet ;  black  soil.  2  feet ;  brown  sandy 

clay,  11  feet;  sand,  5  feet. 
No  rock  struck. 

Wells  110  to  117  feet  through  till. 
Much  sand  and  grax'el  in  wells  80  feet  in  depth. 
Mainly  blue  till ;  sand  at  bottom. 
Yellow  clay,  10  or  12  feet;  gravel,  6  feet;  blue  clay, 

12  or  14  feet;  blue  clayey  sand,  18  feet;  sand,  25 

feet. 
Strong  wells  at  100  to  150  feet  in  sand  below  till. 

Inflammable  gas  in  several  wells. 
Mainly  blue  till,  98  feet;  sand,  42  feet. 
Wells  100  to  175  feet  penetrate  80  or  100  feet  of  till, 

then  saud  and  gravel  to  bottom. 
Alternations  of  sand  and  till. 


LIVINGSTON    COUNTY. 


GENERAL    STATEMENT. 


Livingston  County  is  situated  west  of  Ford  and  Kankakee  counties, 
its  western  border  reaching  nearly. tlie  middle  of  the  State.  It  has  an  area 
of  1,026  square  miles,  and  Pontiac  is  the  county  seat.  Vermilion  River 
traverses  the  county  from  southeast  to  northwest  nearly  centrally.  Its 
tributaries  are  almost  entirely  on  the  western  side  of  the  stream,  the  eastern 
side   being   occupied   by   the   Marseilles   moraiiiic   system   and   an   earlier 


WELLS  OF  LIVINGSTON  COUNTY,  ILLINOIS.  665 

moraine  (Chalsworth-Cayuga  Ridge)  classed  in  the  Bloomington  system. 
The  northeast  part  of  the  county  drains  northward  tlii'ough  Mazon  Creek. 

Aside  from  the  moraines  just  referred  to,  which  traverse  the  central 
portion  of  the  county  in  a  northwest  to  southeast  course,  and  which  occupy 
a  belt  with  an  average  width  of  about  10  miles,  the  surface  of  the  county 
is  very  flat.  Nearly  all  the  streams  of  the  county  flow  in  mere  ditches 
channeled  to  a  level  but  a  few  feet  below  the  plains. 

With  the  exception  of  a  narrow  strip  along  Vermilion  River  from  near 
Fairbury  to  Sti'eator,  where  rock  is  frequently  exposed,  the  count}^  has  a 
heavy  deposit  of  drift  averaging  possibly  150  feet  in  thickness. 

There  appear  to  be  buried  valleys  traversing  the  county  whose  rock 
floors  are  150  to  200  feet  below  the  general  level  of  the  rock  surface.  In 
such  valleys  the  drift  is  over  300  feet  in  thickness.  On  the  borders  of  Ver- 
milion River  nearly  all  of  the  thin  sheet  of  drift  is  sand  and  gravel. 
With  this  exception  the  county  is  generallv  covered  with  a  tliick  sheet  of 
blue  till,  which  is  oxidized  for  a  few  feet  at  the  surface.  On  the  Marseilles 
moraine  in  this  county  a  blue  till  is  found  at  less  depth  than  at  any  other 
points  noted  in  the  State,  in  places  within  2  or  3  feet  of  the  surface,  there 
being  very  little  yellow  or  oxidized  till.  Usually  the  yellow  till  is  6  to  10 
feet  in  depth  both  on  this  moraine  and  later  ones. 

Neai'ly  all  the  well  sections  obtained  in  this  county  are  located  in  the 
northeast  one-half,  the  southwest  part  having-  been  covered  only  by  a  hasty 
reconnaissance.  Along  the  Marseilles  moraine  and  also  on  the  plain  to  the 
northeast  wells  are  frequently  sunk  to  a  depth  of  100  feet  en-  more,  and 
better  supplies  appear  to  occur  at  that  depth  than  nearer  the  smface. 

INDIVIDUAL    WELLS. 

The  public  water  supply  at  the  city  of  Dwight  is  obtained  from  two 
wells  sunk  to  a  depth  of  135  feet  in  the  glacial  drift.  The  water  rises 
within  5  feet  of  the  surface.  A  boring  for  coal  at  this  town'  entered  shale 
at  about  100  feet.  The  record  of  a  private  well  in  the  northeast  part  of  the 
town  is  as  follows: 

Section  of  well  at  Dwif/ht,  Illinois. 

Feet. 

Yellow  till 17 

Blue  till 83 

Hard  yellow  till 17 

Total , 117 

Sand  at  bottom  from  which  water  rises  within  5  or  6  feet  of  surface. 


666  THE  ILLINOIS  GLACIAL  LOBE. 

At  Odell  wells  are  obtained  at  30  or  40  feet.  The  di-ift  varies  greatly 
in  thickness  within  the  limits  of  this  village.  A  well  at  the  Chicago  and 
Alton  Railway  station  entered  rock  after  penetrating  138  feet  of  till; 
another,  on  the  Spencer  farm  near  the  western  limits  of  the  town,  entered 
rock  at  168  feet,  but  a  boi'ing  made  by  Mr.  Matteson  in  the  South  part  of 
the  town  penetrated  360  feet  of  di'ift.  An  experimental  gas  boring  about 
3^  miles  soutliAvest  of  Odell  penetrated  300  feet  of  drift.  The  deep  drift 
at  Mr.  Matteson's  well  in  OdeU  is  mainly  till  to  a  deptk  of  200  feet,  beneath 
which  is  sand. 

At  Nevada  wells  are  usually  obtained  at  30  or  40  feet,  but  records  of 
two  borings  were  collected  which  failed  to  obtain  water  at  a  depth  of  100 
feet.     They  are  mainly  through  blue  till. 

At  Cornell  and  in  its  vicinity  wells  are  obtained  at  about  20  feet  in 
sand  and  gravel,  the  ^^llage  being  located  on  the  low  gravelly  plain  bor- 
dering Vermilion  River. 

At  Pontiac  wells  frequently  enter  limestone  at  a  depth  of  10  to  25 
feet  and  obtain  water  at  comparatively  shallow  depths.  The  public  supply 
is  pumped  from  Vermilion  River. ^  An  area  of  sandy  drift  extends  several 
miles  south  of  this  city  and  wells  are  there  obtained  at  shallow  depth  with- 
out entering  rock. 

At  Fairbury  the  public  water  supply  is  from  a  well  2,002  feet  in 
depth,  from  which  water  rises  within  60  feet  of  the  surface.  The  well 
is  cased  about  365  feet.  Wells  are  usually  obtained  in  that  vicinity  at 
about  25  feet  in  a  gravelly  drift.  Coal  shafts  in  the  vicinity  enter  rock 
at  50  to  90  feet. 

At  Forest  strong  wells  are  obtained  at  25  or  30  feet  and  juauy  wells 
are  only  10  or  12  feet  in  depth.  Coal  shafts  and  other  borings  in  the  vicinity 
show  the  drift  to  be  about  150  feet  in  thickness  and  largely  till  in  the 
lower  part. 

At  Chatsworth  the  public  water  supply  is  from  a  well  sunk  to  a  depth 
of  67  feet  in  the  glacial  drift,  mainly  through  till.  Several  wells  in  this 
village  are  about  50  feet  in  depth,  and  a  few  are  80  feet,  without  entering- 
rock.  Two  coal  borings  reported  in  the  Geology  of  Illinois  show  much 
difference  in  the  distance  to  rock.  One  in  the  southeast  part  of  sec.  4 
enters  rock  at  84  feet,  while  another,  one  mile  east,  at  about  the  same  ele- 


'  Manual  of  American  Waterworks,  1897. 


WELLS  OF  LIVINGSTOJf  COUNTY,  ILLINOIS. 


667 


vation,  struck  rock  at  221  feet.^  The  latter  boring'  had  hard  till  in  the 
lower  part  of  the  drift,  while  the  former  passed  through  a  "dirt  bed  with 
wood"  just  before  entering  rock. 

In  the  vicinity  of  Risk  and  Strawn,  in  the  south  part  of  the  county, 
there  is  about  90  feet  of  drift  as  determined  by  coal  borings,  but  wells  are 
usually  obtained  at  50  feet  or  less  in  sand  below  till. 

The  public  supply  at  Flanagan  is  reported  by  the  Manual  of  American 
Waterworks  to  be  from  an  artesian  well,  but  no  data  are  given  as  to  depth 
or  head. 

Coal  borings  made  at  the  villages  of  Cullom,  Saunemin,  and  Campus, 
in  the  east  part  of  the  county,  penetrate  171,  162,  and  125  feet  of  drift, 
respectively,  but  wells  at  these  villages  are  obtained  at  moderate  depths, 
seldom  exceeding  40  feet  in  sand  or  gravel  below  till.  The  Manual  of 
American  Waterworks  reports  that  Campus  obtains  its  public  water  supply 
from  a  driven  well. 

In  some  places  water  is  very  difficult  to  obtain  at  moderate  depths; 
thus,  at  the  village  of  Grriswold,  several  borings  have  been  sunk  to  a  depth 
of  75  feet  without  obtaining  strong  wells. 

Outside  the  villages  just  discussed  only  a  few  records  of  wells  have 
been  obtained,  and  these  include  the  deepest  of  which  the  wi'iter  has 
obtained  information : 

Wells  in  Livingston  County. 


Owner  or  location. 


Sec.  1,  T.  30,  R.  5  E 

Sec.  12,  T.  30,  E.  5  E 

Sec.  18,  T.  30,  E.  5  E 

Mr.  Adams,  at  Blackstone 

Mr.  Budd,  at  Budd  Station 

Sec.  14,  T.  29,  E.  5  E 

Northeast  part  T.  39,  E.  5  E . . . . 

Sec.  25,  T.  29,  E.  5  E 

Sec.27,T.29,E.5E 

Sec.33,T.29,  E.6E 

Cayuga  

4  miles  south  of  Odell 


Altitude 
(above  tide). 


Depth. 


Remarks. 


Feet.  Feet. 

700  216  Eock  entered  at  about  200  feet. 

700  135  Water  from  sand  below  blue  till. 

750  80  Mainly  till;  no  rock. 

733  200  Rock  entered  at  160  feet;  drift  mainly  till. 

702  160  Enters  rock  at  160  feet. 

700  130  Mainly  till;  no  rock. 

700  100  Several  wells  70  to  100  feet,  from  sand  below  till. 

650  130  Flowing  well  from  sand  below  till. 

650  78  Several  wells  60  to  78  feet;  from  sand  below  till. 

700  60  Flowing  well  from  sand  below  till. 

685  100  Eock.at  100  feet;  drift  mainly  tiU. 

700  68  Flowing  well  from  sand  below  till. 

Geology  of  Illinois,  Vol.  VI,  pp.  243,  244. 


668 


THE  ILLINOIS  GLACIAL  LOBE. 

Wells  in  lAvingston  County — Continued. 


Owner  or  location. 

Altitude 
(abovetide). 

Depth. 

Eeniarka. 

Sec.  33.  T.  29,  R.  7  E 

Feet. 
725 
700 
675 
675 
650 
.   650 

700 
760 
700 
800 

Feet. 
185 
90 
80 
130 
103 
150 

73 
185 

85 
100 

No  rock  struck;  mainly  till. 

Mainly  blue  till. 

No  roek  *  enters  hard  till  at  .56  feet 

See  29  T  28  R  8  E 

Sec.  36,  T.  28  E.  8  E 

Sec.  16,  T.  28,  R.  7  E 

Several  wells  in  sand  below  till 

Sec.  2,  T.  27,  R.  8  E 

No  rock  struck 

Sec.4,  T.  27,  E.  8  E 

Till,  30  feet ;    gravel  and  sand,  40  feet ;   remainder 

rock,  80  feet. 
Water  from  sand  below  till. 

Sec.  7,  T.  27,  E.  7  E      

Sec.  34,  T.  27,  R.  7  E 

No  rock;  mainly  blue  till. 
Schoolhouse  well  in  sand  below  till 

Sec.  17,  T.  27,  R.  7  E  -           .     . . 

Sees.  16, 17,  20, 21,  T.  26,  R.  8  E  . 

Several  wells  70  to  100  feet  froiu  sand  below  till. 

MARSHALL  COUNTY. 


GENERAL   STATEMENT. 


Marshall  County  is  situated  on  tlie  borders  of  the  Illinois  River  south 
of  Bureau  and  Putnam  counties.  It  has  an  area  of  400  square  miles,  and 
Lacon  is  the  county  seat.  About  two-thirds  of  the  county  is  situated  east 
of  the  Illinois  River  and  is  mainly  a  plain  standing  about  300  feet  above 
the  river.  Sandy  Creek  and  Crow  Creek  lead  westward  entirely  across 
this  portion  of  the  county,  the  former  draining  the  north  and  the  latter  the 
south  border.  The  portion  west  of  the  Illinois  rises  on  the  western  border 
to  an  elevation  fully  400  feet  above  the  Illinois  River,  or  about  850  feet 
above  tide,  there  being  a  prominent  morainic  belt  (the  outer  moraine  of  the 
Wisconsin  series)  traversing  the  western  edge  of  the  county  from  north  to 
south. 

The  broad  valley  of  the  Illinois  River,  averaging  about  5  miles  in  width, 
is  filled  to  a  depth  of  about  150  feet  with  gravel  and  sand.  The  well  at 
Henry,  on  one  of  the  terraces  (not  the  highest),  reached  rock  at  135  feet, 
and  wells  above  this  Anllage  in  Putnam  County  strike  rock  at  correspond- 
ingly low  level  Tlie  western  jiortion  of  the  county  lias  a  thin  sheet  of 
drift  on  the  borders  of  the  Illinois  Valley,  but  there  is  a  heavy  deposit  along 
the  moraine.  The  eastern  portion  of  the  county  is  apparently  heavily  cov- 
crcil  tliroiighout,  there  being  only  occasional  slight  exposures  of  rock  in  the 


WELLS  OF  MARSHALL  COUNTY,  ILLINOIS.  6B9 

east  bluff  of  the  Illinois  River  or  along'  its  tributaries.  At  Wenona,  on  the 
eastern  border  of  the  county,  the  drift  is  about  100  feet  in  thickness  and  is 
of  similar  depth  at  Toluca.  These  are  the  only  points  at  which  the  distance 
to  rock  in  that  part  of  the  county  has  been  ascertained. 

But  few  records  of  wells  were  obtained  in  this  county,  only  a  hasty 
reconnaissance  having  been  made.  Nothing  was  learned  to  indicate  that 
wells  are  difficult  to  obtain. 

INDIVIDUAL   WELLS. 

At  Henry  wells  are  usually  obtained  at  a  depth  of  60  or  70  feet  in  tl'e 
sand  of  the  Illinois  River  bottom.  But  a  few  reach  a  depth  of  100  or  110 
feet.  An  artesian  well  1,300  feet  in  depth  obtains  a  "white  sulphur"  water 
in  its  lower  part,  pi'obably  either  from  the  Lockpoi't  (Niagara)  or  Galena 
limestone.  The  drift  at  this  well  is  135  feet  in  depth.  The  discharge  of 
the  well  is  estimated  at  32  gallons  per  minute  from  a  pipe  3^  inches  in 
diameter 

At  Lacon  wells  are  usually  obtained  in  the  sand  of  the  Illinois  River 
Valley  at  a  depth  of  about  60  feet,  though  on  a  higher  terrace  in  the  east 
part  of  the  village  a  depth  of  about  100  feet  is  reached.  It  is  reported  that 
some  of  the  wells  in  the  lower  part  of  the  city  strike  a  limestone  at  about 
60  feet,  but  no  very  authentic  data  could  be  obtained.  The  Manual  of 
American  Waterworks  reports  that  the  public  water  supply  is  from  a  well, 
depth  not  given. 

The  public  water  supply  at  Wenona  is  obtained  from  a  well  1,854  feet 
in  depth  which  is  reported  by  residents  to  have  entered  the  Potsdam  near 
the  bottom,  but  perhaps  terminated  in  St.  Peter  sandstone.  It  has  a  head 
120  feet  below  the  surface,  or  565  feet  above  tide.  The  capacity  is  estimated 
at  100  gallons  per  minute.  Strong  wells  are  obtained  from  the  diift  in  the 
vicinity  of  Wenona  at  depths  of  40  to  60  feet.  The  drift  in  that  vicinity,  as 
already  noted,  is  about  100  feet  in  depth. 

At  Toluca  the  coal  shafts  encounter  a  large  amount  of  water  in  the 
lower  part  of  the  drift  and  also  in  the  sandstones  of  the  Coal  Measures. 
It  is  proposed  to  utilize  the  water  from  one  of  these  horizons  as  the  public 
supply,  but  at  last  reports  (in  1897)  the  waterworks  had  not  been  constructed. 


670  THE  ILLINOIS  GLACIAL  LOBE. 


WOODFORD    COUNTY. 
GENERAL   STATEMENT. 


Woodford  County  is  situated  on  the  east  side  of  the  Illinois  River, 
immediately  south  of  Marshall  and  Lasalle  counties,  and  has  an  area  of 
540  square  miles,  with  Metamora  as  the  county  seat.  The  northwestern 
portion  is  directly  tributary  to  the  Illinois  River,  through  small  streams. 
The  remainder  of  the  county  is  tribiitary  to  the  Mackinaw  River,  which 
crosses  its  southeast  border. 

This  is  one  of  the  most  elevated  counties  of  central  Illinois,  the  uplands 
being  in  places  about  850  feet  and  generally  750  feet  or  more  above  tide. 
The  Illinois  River,  on  the  west  border  of  the  county,  is  only  about  430 
feet  above  tide,  thus  making  a  valley  fully  400  feet  in  depth.  The  small 
streams,  therefore,  leading  down  to  the  valley  make  very  rapid  descent. 
The  southwestern  border  of  the  county  is  crossed  by  the  Bloomington 
morainic  system,  which  has  a  subdued  expression  and  rises  so  gradually 
from  the  plain  on  the  east  that  it  would  scarcely  attract  notice,  though  it 
stands  about  50  feet  higher  than  the  plain. 

There  is  a  heavy  deposit  of  drift  covering  the  entire  county,  if  we  may 
judge  from  the  outcrops  and  the  few  wells  which  have  reached  rock,  the 
thickness  at  Metamora  being  280  feet,  at  Eureka  150,  and  at  Minonk  about 
125  feet.  Outcrops  of  rock  are  reported  in  a  few  places  in  the  south  part 
of  the  county  on  tributaries  of  Mackinaw  River,  and  a  single  outcrop  occurs 
on  Panther  Creek  in  the  noi'thwest  part.  So  far  as  known  to  the  wi'iter 
there  are  no  outcrops  in  the  Illinois  River  bluffs. 


INDIVIDUAL   WELLS. 


The  public  water  suppl}^  for  Minonk  is  obtained  from  a  well  1,755  feet 
in  depth,  which  has  a  head  about  150  feet  below  the  surface,  or  600  feet 
above  tide.  Water  veins  are  encountered  in  the  Eocarboniferous  lime- 
stone at  about  750  feet,  but  a  supply  with  greater  head  and  volume  was 
obtained  in  the  lower  part  of  the  well,  at  about  1,700  feet,  perhaps,  from 
the  St.  Peter  sandstone,  no  careful  record  being  available.  The  water  is 
moderately  hard  and  the  well  has  an  estimated  capacity  of  100  gallons  per 
minute.  An  abundance  of  water  is  obtained  from  the  drift  in  this  Aacinity 
frum  a  depth  of  65  feet  downward,  rock  usually  being  struck  at  about  125 


WELLS  OF  WOODFORD  COUNTY,  ILLINOIS.  67 1 

feet.  A  record  of  the  M.  T.  Ames  coal  shaft  at  Minonk  shows  yellow  and 
blue  tills  to  a  depth  of  62  feet,  beneath  which  a  harder  till  is  entered,  which 
is  interbedded  with  sand. 

At  Elpaso  the  strongest  wells  are  obtained,  at  about  115  feet,  from  sand 
beds  in  the  drift.     The  public  water  supply  is  obtained  from  such  wells. 

The  strongest  wells  in  Eureka  are  found  in  beds  of  sand  and  gravel  at 
a  depth  of  60  to  100  feet.  The  waterworks  are  supplied  from  wells  of  this 
class  60  feet  in  depth.  Private  wells  are  often  obtained  at  depths  of  but  15 
feet.  The  following  detailed  record  of  a  prospect  boring  for  coal  at  this 
town  will  serve  to  indicate  the  complexity  of  the  drift  beds.  It  is  a  copy  of 
a  sworn  statement  made  to  the  coal  company  by  Gr.  W.  Darling,  who  did 
the  drilling: 

Section  of  prospect  boring  for  coal  at  Eureka^  Illinois. 

1.  Top  soil  had  been  removed.  Feet. 

2.  Hardpan 8 

3.  Blue  clay  and  gravel 4 

4.  Bowlders  and  large  stones 2 

5.  Coarse  loose  gravel  and  water 5 

6.  Dark  clay 2 

7.  Variegated  clay,  different  colors,  witli  gravel 8 

8.  Bowlders  bedded  in  clay 6 

9.  Cement  gravel 41 

10.  Very  soft  sand  rock 3 

11.  Quicksand,  some  water 2 

12.  Coarse  gravel i 

13.  Clay  and  gravel 24 

14.  Drift  formation,  gravel  and  sand 1 

15.  Wood  drift 1 

16.  Different  colored  clay  with  some  stone 43 

17.  Soft  soapstone 12 

18.  Hard  blue  soapstone 37 

19.  Black  shale 3j. 

20.  Coarse  coal  and  sulphur Oj. 

21.  Good  coal  (splendid  coal ) _ 2 

22.  Coal  debris  (or  horseback) Ij. 

23.  Soapstone 9 

24.  Limestone _ 14 

25.  Soapstone 34. 

26.  Limestone 2* 

27.  Soapstone 7 

28.  Conglomerate  rock,  composed  of  sulphur,  lime,  iiint,  and  iron 3 

29.  Soapstone 47 

30.  Blue  hard  slate 9| 

31.  Black  slate,  rather  soft Xi 

32.  Hard  coal 3. 1 

33.  Fire  clay O^V 

34.  Soapstone OJ 


672  THE  ILLINOIS  GLACIAL  LOBE. 

At  Metamora  stroug  wells  are  obtained  at  about  75  feet.  A  few  wells 
in  the  vicinity  of  this  town  have  been  sunk  to  greater  depths  and  some  of 
them  pass  throvigh  a  black  muck  containing  wood  under  the  blue  till  at  a 
depth  of  about  140  feet.  This  muck  and  associated  sand  is  in  some  cases 
15  feet  in  thickness.  A  thin  bed  of  blue  clay  underlies  it,  beneath  which 
is  a  hard  gray  till,  which  in  a  single  boring,  reaching  the  rock,  was  115  feet 
in  depth. 

STARK  COUNTY. 

aENBRAL    STATEMENT. 

Stark  County  is  situated  west  (if  Marshall  and  has  an  area  of  290 
square  miles,  with  Toulon  as  the  count)'-  seat.  It  is  drained  by  the  two 
headwater  forks  of  Spoon  River,  which  lead  southward  tlxrough  it  and  unite 
just  below  the  county  line.  The  original  drift  surface  was  probably  nearly 
plane,  but  has  been  much  eroded  by  the  streams,  for  this  county  lies  outside 
the  limits  of  the  Wisconsin  and  probably  of  the  lowan  sheet  of  drift,  and 
in  consequence  has  been  subjected  to  erosion  for  a  longer  period  than 
counties  to  the  east. 

The  surface  of  the  county  is  capped  with  loess  to  a  depth  of  about  15 
feet,  beneath  which  is  a  deposit  of  glacial  drift  seldom  more  than  50  feet 
deep  and  in  many  places  but  10  or  15  feet.  Wells  are  ordinarily  obtained 
in  the  di-ift,  but  a  few  obtain  water  in  the  rock  at  moderate  depths. 

INDIVIDUAL   "WELLS. 

At  Toulon  and  in  that  vicinity  rock  is  entered  at  about  30  feet  and 
water  is  usually  obtained  near  the  base  of  the  drift. 

In  the  vicinity  of  Wyoming  many  of  the  wells  encounter  a  bed  of 
muck  or  peat  at  a  depth  of  20  to  24  feet.  This  is  said  to  be  overlaid  by  a 
blue  cla}',  Ijut  opportunity  has  not  been  afforded  for  determining  whether 
it  is  a  glacial  deposit  or  a  part  of  the  loess.  The  wells  are  usually  obtained 
in  sand  beneath  this  peat. 

In  the  vicinity  of  Stark,  on  a  low  plain  in  the  south  ]iart  of  the  count v, 
about  40  feet  below  the  general  level  of  the  upland,  wells  reach  a  depth  of 
40  feet  or  more  without  enterinsr  rock. 


WELLS  OF  PEORIA  COUNTY,  ILLi:srOIS.  673 

PEORIA    COUNTY. 
GENERAL    STATEMENT. 

Peoria  County  is  situated  on  the  west  side  of  the  Illinois  River,  imme- 
diately south  of  Stark  and  western  Marshall,  and  opposite  Woodford  and 
Tazewell  counties.  It  has  an  area  of  615  square  miles,  and  Peoi'ia  is  the 
county  seat.  The  principal  stream  crossing  the  county  is  Kickapoo  Creek, 
which  lias  two  forks,  one  of  which  drains  the  northern  and  the  other  the 
western  portion  of  the  county.  The  stream  enters  the  Illinois  just  below 
the  city  of  Peoria.  The  other  direct  tributaries  of  the  Illinois  are  very 
small.  Spoon  River  crosses  the  extreme  northwest  corner  of  the  county  in 
a  westward  course  and  flows  through  Knox  and  Fulton  counties  before 
joining  the  Illinois  River. 

The  northeastern  part  of  the  county  is  occupied  by  two  bulky  morainic 
systems,  the  Shelbyville  and  Bloomington.  West  from  these  moraines  the 
uplands  are  generally  plane  and  stand  about  100  feet  lower  than  the  main 
crests  of  the  morainic  systems.  Like  the  neighboring  portion  of  Stark 
County,  this  plane  is  covered  with  loess  to  a  depth  of  12  to  15  feet.  The 
morainic  ridges  to  the  east  are  in  places  nearly  destitute  of  loess,  so  that 
surface  bowlders  are  a  conspicuous  feature.  There  are  other  portions  of 
the  moraines,  however,  which  carry  a  deposit  of  loess-like  silt  5  or  6  feet  in 
depth.  The  sheet  of  loess  which  covers  the  plain  west  of  the  moraines 
passes  under  them,  as  indicated  on  a  previous  page  (p.  187).  The  thick- 
ness of  the  drift  in  Peoria  County  is  similar  to  that  of  Stark,  except  that 
the  Illinois  Valley  and  the  moraine  in  the  northeastern  part  of  the  county 
each  have  a  very  heavy  drift  deposit,  150  to  200  feet  or  more  in  thickness. 
The  drift  usually  contains  a  sufficient  amount  of  sand  and  gravel  at 
moderate  depths  to  afford  water  for  Avells,  and  in  places  the  entire  drift 
section  appears  to  be  composed  of  sand  and  gravel.  The  majority  of 
exposures  along  Kickapoo  Creek  are  largely  of  this  material,  there  being 
but  a  small  amount  of  till  exposed.  In  the  morainic  ridges  in  the  northeast 
part  of  the  county  much  till  is  tisually  found  in  wells.  Excellent  exposures 
of  the  till  are  to  be  seen  along  the  Santa  Fe  Railroad  in  its  descent  to  the 
Illinois  Valley  between  Edelstein  and  Chillicothe. 

JION  xxxviii 43 


674  THE  ILLINOIS  GLACIAL  LOBE. 


INDIVIDXTAL    WELLS. 


In  the  vicinitv  of  Princeville,  in  the  northern  part  of  the  county,  wells 
obtain  water  in  limestone  at  depths  of  20  to  50  feet,  but  at  Monica,  only  4 
miles  west,  100  feet  of  drift  is  penetrated,  and  at  Dunlap,  6  miles  southeast, 
wells  occasionally  pass  through  200  feet  of  drift.  The  drift  appears  to 
have  built  up  an  eroded  country  to  a  level  about  even  Avith  the  tops  of  the 
rock  ridges.  Occasionally  a  rock  ridge  rises  slig'htly  above  the  general 
level,  an  instance  being  found  in  sees.  4  and  5,  T.  11,  R.  7  E.,  about  4 
miles  northeast  of  Princeville,  where  the  rock  appears  at  the  top  of  a  ridge 
standing  40  feet  higher  than  Princeville  Station. 

Records  of  several  deep  wells  made  near  Dunlap  and  Alta  have  been 
obtained  from  the  driller,  Mr.  Alexander  Lutcavish.  In  the  Aallage  of  Dun- 
lap several  wells  obtain  a  strong  supply  of  water  at  110  to  112  feet  Avithout 
entering  the  rock.  Nearly  all  the  wells  find  a  weak  vein  at  65  to  70  feet, 
which  is  apparently  at  the  base  of  the  Wisconsin  till  sheet.  Occasionally 
strong  wells  are  obtained  at  this  depth.  A  well  at  Harrison  Harlan's,  2 
miles  south  of  Dunlap,  and  at  an  altitude  about  50  feet  lower  than  the  vil- 
lage, obtains  water  from  sand  and  gravel  at  a  depth  of  117  feet.  It  is 
mainly  tlu'ough  a  stony  blue  clay.  At  William  Rodgers's,  1^  miles  west  of 
Dunlap,  on  the  crest  of  the  Shelbyville  moraine,  at  an  altitude  about  50 
feet  above  the  village,  a  well  reaches  a  depth  of  150  feet  without  entering 
rock.  Another  well  at  Mr.  Powers's,  also  on  the  ci-est  of  the  moraine,  about 
a  mile  south  from  Mr.  Rodgers's,  is  of  similar  depth,  and  also  fails  to  reach 
rock.  A  well  on  "Jubilee  Mound,"  about  5  miles  west  of  Dunlap,  45  feet 
in  depth,  passes  through  30  feet  of  yellow  till  and  then  enters  a  very  hard 
blue  till  containing  large  bowlders.  Blasting  was  necessary  to  remove  this 
blue  till.  This  mound  is  outside  the  limits  of  the  Wisconsin  drift.  Mr. 
Lutcavisli  made  a  boring  for  John  Holmes,  sr.,  one  mile  east  of  Alta,  which' 
reached  a  depth  of  370  feet,  and  apparently  did  not  strike  rock.  Its  lower 
portion  was  in  a  sand  too  fine  to  be  screened  b}'  a  pump  strainer.  A  bed 
of  muck  with  wood  and  leaves  was  passed  through  at  a  depth  of  245  to  247 
feet.  This  well  is  near  the  crest  of  the  main  ridge  of  the  Bloomington 
moi'ainic  system,  at  an  altitude  nearly  400  feet  aboA'^e  the  Illinois  RiA^er. 
At  the  farm  of  John  Holmes,  jr.,  one-half  mile  Avest  of  Alta,  a  Avell  Avas 
obtained  at  a  depth  of  125  feet,  Avhich  has  80  feet  of  Avater.     Mr.  William 


WELLS  OF  PEOEIA  COUNTY,  ILLINOIS.  675 

Dickison  has  a  well  on  the  crest  of  the  Shelby ville  moraine,  2  J  miles  west 
of  Alta,  which  was  dug  to  a  depth  of  156  feet.  It  entered  blue  till  at  less 
than  10  feet  and  continued  in  it  to  a  depth  of  117  feet,  when  a  thin  bed  of 
very  bowldery  clay  was  encountered,  which  apparently  marks  the  base  of 
the  Wisconsin  drift.  Beneath  this  clay  is  a  deposit  of  loess  several  feet  in 
depth  which  connects  with  the  surface  loess  of  the  districts  to  the  west  out- 
side the  limits  of  the  Wisconsin  drift.  Beneath  the  loess  is  a  hard  till 
(lllinoian)  alternating  with  beds  of  sand.  Water  is  obtained  in  gravel  near 
the  bottom  of  the  well  and  rises  only  to  20  feet.  Mr.  John  Miller  made  a 
well  4  miles  north  of  Dunlap  which  obtained  water  from  sand  and  gravel 
at  a  depth  of  218  feet.  The  upper  68  feet  is  evidently  Wisconsin  di-ift, 
while  the  remainder  is  lllinoian.  The  drift  is  almost  entirely  till.  A  well 
was  made  for  Mr.  Patrick  Hogan  about  4  miles  south  of  Alta  which  reached 
a  depth  of  330  feet.  Wliether  it  entered  rock  was  not  ascertained.  The 
well  is  on  the  crest  of  the  Shelby  ville  moraine,  at  an  altitude  about  375 
feet  above  the  Illinois  River. 

In  Elmwood  and  vicinity,  in  the  west  part  of  the  county,  wells  are 
usually  obtained  at  25  to  40  feet.  The  drift  in  that  vicinity  is  about  60 
feet  in  depth.  The  Manual  of  American  Waterworks  reports  that  the  public 
water  supply  is  from  an  artesian  Avell,  depth  not  given. 

At  Peoria  the  public  water  supply  is  obtained  from  a  large  well  32  feet 
in  diameter  and  50  feet  in  depth,  sunk  in  the  low  bottom  of  the  Illinois 
River  just  above  the  city.  The  well  passes  through  a  bed  of  blue  till  and 
obtains  water  from  gravel  near  the  bottom.  The  city  engineer,  Mr.  J.  A. 
Harman,  reports  that  the  well  will  supply  8,000,000  gallons  per  day,  even 
in  dry  seasons.  It  is  thought  that  the  bed  of  blue  till  overlying  the  water- 
bearing gravel  protects  the  water  from  contamination  by  access  of  Illinois 
River  water,  or  at  least  there  is  a  probability  that  any  water  entering  this 
gravel  from  the  Illinois  River  passes  tln*ough  a  sufficient  amount  of  sand  and 
gravel  before  reaching  the  well  to  insure  the  absorption  of  much  of  the 
impurities.  Mr.  Harman  states  that  this  water  is  preferable  to  water  obtained 
from  the  underlying  rock  strata,  for  the  latter  water  in  this  vicinity  is  brack- 
ish. Several  deep  wells  have  been  sunk  in  the  city  at  the  distilleries,  stock 
yards,  and  by  private  parties.  One  of  these  wells,  controlled  by  D.  L.  Big- 
ham,  is  used  to  supply  the  bath  house  on  Adams  street,  between  Hamilton 
and  Fayette.     This  well  penetrated  151  feet  of  glacial  drift,  and  similar 


676  THE  ILLINOIS  GLACIAL  LOBE. 

depths  have  been  found  in  other  wells  in  the  valley  at  this  city.  They  show 
the  rock  floor  to  be  at  an  altitude  of  350  feet,  or  80  feet  below  the  Illinois 
River.  Possibly  a  deeper  portion  of  the  old  valley  is  to  be  found  farther 
east,  as  these  wells  are  all  situated  near  the  west  bluff. 

Between  Peoria  and  Chillicothe,  on  a  sandy  terrace  of  the  Illinois 
River,  standing  about  100  feet  above  the  present  stream,  several  wells  have 
been  sunk  to  de^Dths  of  90  to  120  feet.  They  apparently  obtain  water  at 
about  the  level  of  the  Illinois  River.  A  few  wells  on  this  terrace  near  the 
west  bluff  obtain  water  at  50  to  75  feet. 

The  Manual  of  American  Waterworks  reports  that  the  public  water 
supply  at  Chillicothe  is  from  driven  wells,  depth  not  given. 

KNOX  COUNTY. 

GENERAL   STATEMENT. 

Knox  County  is  situated  in  western  Illinois  immediately  west  of  Stark 
and  Peoria  counties.  It  has  an  area  of  720  square  miles,  and  Galesburg  is 
the  county  seat.  The  southeastern  portion  of  the  county  is  crossed  by 
Spoon  River  in  a  southwestward  course,  and  about  tliree-fourths  of  the 
county  is  tributary  to  that  stream.  The  northwest  one-fourth  of  the  county 
drains  directly  westward  to  the  Mississippi  River  through  Pope  Creek  and 
two  branches  of  Henderson  River.  The  county  has  a  good  surface  drain- 
age, the  drainage  systems  being  well  matured  and  the  slopes  between 
streams  sufficiently  rapid  to  insure  the  discharge  of  water  not  absorbed  by 
the  soil.  The  loess,  which  forms  a  capping  about  15  feet  in  thickness,  is 
sufficiently  porous  to  readily  absorb  a  large  part  of  the  rainfall  and  retm-n 
it  to  the  crops  in  seasons  of  drought. 

The  glacial  drift  is  generally  but  20  or  30  feet  in  depth,  but  in  places 
where  valleys  have  been  filled  the  depth  may  reach  100  feet  or  more.  The 
average  of  10  borings  which  enter  rock  is  found  to  be  35  feet,  and  this  is 
thought  to  fairly  represent  the  upland  average  for  the  county.  The  majority 
of  wells  are  obtained  in  the  drift,  some  being  sunk  only  to  the  base  of  the 
loess.  The  strong  wells,  however,  usually  penetrate  the  glacial  drift  a  short 
distance. 

INDIVIDUAL   WELLS. 

At  Galesburg  the  public  water  supply  is  obtained  in  part  from  Avells  in 
the  drift  and  in  pni't  from  deep  wells  sunk  to  the  St.  Peter  sandstone.     The 


WELLS  OF  KNOX  COUJfTT,  ILLINOIS.  677 

wells  ill  the  drift  are  located  along  a  valley  leading  westward  from  the  town, 
and  are  sunk  to  depths  of  70  or  80'  feet  without  entering  rock.  They  are 
mainly  through  sand,  and  the  water  rises  nearly  to  the  surface.  A  well  was 
sunk  in  1896  to  a  depth  of  1,226  feet,  entering  St.  Peter  sandstone  at  1,060 
feet.  The  well  is  cased  to  the  St.  Peter  and  the  entire  depth  j)enetrated  in 
this  formation  is  thought  to  be  a  water-yielding  rock.  The  water  has  a 
temperature  of  60°  F.  The  head  is  102  feet  below  the  surface  and  635 
feet  above  tide,  as  determined  by  careful  measurements  conducted  b}'  the 
city  engineer.  The  capacity  is  estimated  at  120  gallons  per  minute.  As 
this  is  but  one-eighth  the  amount  needed  by  the  city,  the  drift  wells  furnish 
the  greater  part  of  the  supply.  It  is  planned  to  sink  other  deep  wells  in 
order  to  dispense  with  the  water  from  the  drift,  since  that  is  not  entirely 
above  suspicion  of  surface  contamination.  Many  private  wells  in  this  city 
are  obtained  from  sand  below  loess  and  till  at  depths  of  25  to  45  feet.  The 
drift  is  said  to  be  80  or  90  feet  in  depth  for  a  distance  of  5  or  6  miles  north- 
east from  Gralesburg,  but  within  a  short  distance  in  other  directions  rock  is 
found  at  much  shallower  depths. 

At  Knoxville  the  public  water  supply  is  obtained  from  a  well  1,350 
feet  in  depth,  which  was  sunk  in  1896.  It  enters  St.  Peter  sandstone  at 
1,180  feet  and  continues  in  that  formation  to  the  bottom.  The  well  is 
cased  to  the  top  of  the  St.  Peter  sandstone  in  order  to  shut  out  sulphurous 
Avater  struck  at  higher  levels.  It  has  an  estimated  capacity  of  80  gallons 
per  minute.  The  water  has  a  temperature  of  68°  F.  Private  wells  are 
obtained  in  the  vicinity  of  Knoxville  at  depths  of  20  to  40  feet,  either  near 
the  base  of  the  drift  or  in  the  underlying  Coal  Measures. 

At  the  villages  of  Wataga,  Oneida,  and  Altona  coal  shafts  usually 
enter  rock  at  about  30  feet,  but  wells  are  obtained  near  the  base  of  the 
drift  or  only  occasionally  from  the  rock. 

At  Williamsfield,  in  the  east  part  of  the  county,  wells  are  usually 
obtained  at  shallow  depths  in  the  glacial  drift,  seldom  exceeding  40  feet. 
The  record  of  a  well  about  1 1  miles  west  of  this  village  is  found  to  show 
85  feet  of  di'ift.  without  entering  rock.  The  cuttings  along  the  Santa  Fe 
Railway  between  Williamsfield  and  Dahinda  expose  a  complex  series  of 
sand  and  till  beds  in  the  descent  to  Spoon  River.  Wells  on  the  bordering 
uplands  appear  to  penetrate  a  similar  complex  series. 

At  Yates,  in  the  southern  portion  of  the  county.  Coal  Measures  shale 


678  THE  ILLINOIS  GLACIAL  LOBE. 

is  entered  at  about  30  feet,  but  wells  are  usually  obtained  without  enter- 
ing the  rock.  A  drift  ridge  leading  east  from  this  town  and  standing  30 
or  35  feet  above  the  general  level  of  the  plain  is  found  to  have  a  black  soil 
beneath  till  at  about  the  level  of  its  base.  This  soil  has  been  struck  in 
several  wells. 

At  Abingdon  wells  are  iisually  obtained  from  rock  at  depths  of  only  25 
or  30  feet.     The  di-ift  is  in  places  but  1 5  feet  in  thickness. 

WARREN    COUNTY. 
GENERAL    STATEMENT. 

"Warren  County  is  situated  immediately  west  of  Knox  and  has  an  area 
of  640  square  miles,  with  Monmouth  as  the  county  seat.  The  drainage  is 
mainly  westward  through  Henderson  River  and  other  streams  into  the 
Mississippi.  The  southeastern  portion  of  the  coimty,  however,  drains 
eastward 'to  Spoon  River.  The  features  of  this  county  are  very  similar  to 
those  of  Knox,  thei'e  being  a  well-drained  surface  and  comparatively  thin 
covering  of  drift.  The  loess  is  fully  as  thick  as  in  Knox  County  and 
equally  pervious  to  water.  At  the  base  of  the  loess  numerous  springs  are 
to  be  seen  where  it  outcrops  along  the  sides  of  ravines. 

INDIVIDITAL    WELLS. 

At  Momnouth  the  public  water  supply  is  from  two  wells,  each  about 
1,227  feet  in  depth.  They  enter  the  St.  Peter  sandstone  156  feet.  One 
was  cased  to  the  top  of  this  sandstone,  but  the  other  was  not  cased  to  so 
gi-eat  a  depth,  for  the  reason  that  a  water  vein  was  found  at  a  depth  of 
about  935  feet  which  seemed  desirable  to  admit  to  the  well.  The  head  in 
the  well  cased  to  the  St.  Peter  sandstone  is  60  feet  below  the  surface  and 
675  feet  above  tide.  No  data  have  been  obtained  concerning  the  head  in 
the  other  well.  The  capacity  of  the  first-named  well  is  estimated  at  200 
gallons  per  minute.  An  analysis  of  its  water  appears  in  the  Seventeenth 
Annual  Report  of  this  Survey.^  Private  wells  of  considerable  strength 
are  obtained  in  the  vicinity  of  Monmouth  at  a  depth  of  about  60  feet,  in 
some  cases  from  the  glacial  drift.  There  are  also  shallower  wells  of  less 
strength. 


I  Part  II,  p.  827. 


WELLS  OF  HENDERSON  COUNTY,  ILLINOTS.  679 

111  the  southeast  part  of  the  county  rock  is  often  struck  on  the  high 
points  at  25  feet  or  less,  but  on  lower  ground  the  drift  is  usually  thicker. 
In  the  southwest  part  of  the  county  the  drift  appears  to  have  an  average 
depth  of  at  least  50  feet,  and  wells  seldom  reach  the  rock. 

The  Manual  of  American  Waterworks  (1897)  reports  that  waterworks 
systems  have  recently  been  introduced  at  Alexis,  Kirkwood,  and  Roseville. 
In  each  village  the  supply  is  from  a  well.  That  at  Kirkwood  is  reported 
to  be  insufficient  for  the  needs  of  tlie  village. 

HENDERSON    COUNTY. 
GENERAL   STATEMENT. 

Henderson  County  borders  the  Mississippi  River  in  the  western  part 
of  the  State,  immediately  west  of  Warren  and  south  of  Mercer  County. 
It  has  an  area  of  380  square  miles,  and  Oquawka  is  the  county  seat.  The 
county  is  drained  mainly  by  Henderson  River  and  its  tributaries,  which 
lead  westward  to  the  Mississippi.  The  southern  portion  is  tributary  to 
Honey  Creek,  which  leads  westward  entirely  across  the  county. 

There  is  a  strip  of  the  Mississippi  bottoms  along  the  west  border  of  the 
county  having  an  average  width  of  about  5  miles,  much  of  which  is  subject 
to  overflow  and  is  sparsely  settled.  The  remainder  of  the  bottom  land  is 
very  sandy.  The  uplands,  which  stand  about  200  feet  above  the  river,  are 
covered  with  loess  to  a  depth  of  20  feet  or  more.  In  places  the  loess  has 
been  heaped  into  dunes  and  ridges  on  the  brow  of  the  bluffs,  which  stand 
50  feet  or  more  above  the  uplands  to  the  east.  In  places  also  sand  in 
dunes  appears  along  the  brow  of  the  bluff. 

But  few  records  of  wells  have  been  obtained  in  this  county,  and  these 
indicate  considerable  difference  in  the  distance  to  rock,  there  being  a  range 
from  20  feet  to  over  160  feet.  The  rock  floor  of  the  Mississippi  Valley 
probably  stands  nearly  160  feet  below  the  level  of  the  bottoms,  its  elevation 
at  Fort  Madison,  Iowa,  just  beyond  the  limits  of  this  county,  being  360  to 
370  feet  above  tide,  or  about  140  feet  below  the  level  of  low  water  at  that 
city.  Preglacial  tributaries  of  this  valley  would  be  excavated  to  a  corre- 
spondingly low  level;  hence  we  may  expect  to  find  a  drift  filling  of  not  less 
than  300  feet  on  the  portions  of  the  uplands  adjacent  to  the  Mississippi, 
where  the  valleys  have  been  filled  to  the  level  of  the  upland  plain. 


680  THE  ILLINOIS  GLACIAL  LOBE. 

INDIVIDUAL    AVKLLS. 

At  Oquawka  wells  are  obtained  by  driving  pipes  to  a  depth  of  4C)  to 
.  GO  feet  in  the  sand  of  the  Mississippi  bottoms,  and  wells  of  this  class  are 
common  tlu'oughont  the  settled  portions  of  these  bottoms. 

In  the  vicinity  of  Biggsville  rock  is  entered  on  the  uplands  at  a  depth 
of  about  40  feet,  but  wells  are  usually  obtained  at  12  to  30  feet.  Similar 
conditions  prevail  in  the  vicinity  of  Media  and  Stronghurst,  though  the 
drift  occasionally  exceeds  50  feet. 

Near  Decorra,  in  the  southwest  part  of  the  count}',  several  wells  have 
been  sunk  to  depths  of  90  to  150  feet.  They  usually  enterrock  within  100 
feet  of  the  surface.  About  2  miles  southeast  of  Decorra  rock  is  struck  in 
several  wells  at  only  30  feet. 

At  Stronghurst  a  deep  well  was  drilled  by  the  Stronghurst-Media 
Company  in  the  winter  of  1897-98  with  a  view  to  obtain  oil.  Instead 
water  was  obtained,  which  rises  to  within  30  feet  of  the  surface,  or  643  feet 
above  tide.  The  log  of  the  well  kept  by  the  drillers,  Wilson  Brothers,  of 
Belleville,  Illinois,  is  as  follows  (names  in  parentheses  are  by  the  writer): 

Section  of  an  oil  boring  at  Stronghurst,  Illinois. 

Feet. 

1.  Glacial  drift,  largely  blue  clay 150 

2.  Gray  shale  (Kinderhook?) 165 

3.  Limestoue  (Devonian  and  Upiier  Siluriaa?) 105 

4.  Shale  (Hudson  River  Group?) 165 

5.  Gray  limestone  (Trenton?) 200 

6.  Brown  limestone  (Trenton?) lo 

7.  Gray  limestone  (Trenton?) 60 

8.  Sandstone  (St.  Peter?) 71 

9.  While  shale 25 

10.  White  limestone 10 

11.  White  shale 5 

12.  White  limestone 24 

13.  White  saudatoiio 20 

14.  Limestone 50 

15.  Shale 5 

16.  Limestone 105 

17.  Sandstone 5 

18.  Limestone 25 

19.  .St.  Croix  (?)  sandstone 290 

20.  Sandstone 6 

Total , 1.601 

There  was  a  strong  yield  of  water  in  the  Trenton  and  in  the  sandstone 
strata  at  lower  dejjths. 


WELLS  OF  HAifOOCK  COUNTY,  ILLINOIS.  681 


HANCOCK  COUNTY. 
GENERAL  STATEMENT. 


Hancock  Coiint}^  borders  on  the  Mississippi  below  Henderson  County 
and  opposite  the  extreme  southeast  corner  of  Iowa.  It  has  an  area  of  769 
square  miles,  and  Carthage  is  the  county  seat.  Although  bordering  the 
Mississippi  RiA^er,  a  considerable  portion  of  the  county  is  tributary  to  the 
Illinois  River.  In  the  north  part  of  the  county  the  divide  between 
the  Illinois  and  Mississippi  rivers  is  only  3  or  4  miles  from  the  east  bluff  of 
the  Mississippi.  The  principal  stream  leading  to  the  Illinois  in  this  county 
is  Crooked  Creek,  which  drains  the  northeastern  fourth  of  the  county.  The 
principal  stream  tributary  to  the  Mississippi  is  Bear  Creek,  which  drains  the 
southwestern  fourth  of  the  county  southward  into  Adams  County  and  thence 
westward  into  the  Mississippi.  Along  much  of  the  northern  half  of  the 
border  of  this  county  the  Mississippi  River  is  in  a  new  course  and  occupies 
the  entire  width  of  its  valley.  The  distance  between  bluffs  is  but  little 
more  than  a  mile.  In  the  remainder  of  the  border  the  river  is  in  a  pregla- 
cial  course,  with  bottoms  6  or  8  miles  in  width.  These  bottoms  are  mainl}- 
on  the  Missouri  side,  though  near  the  south  line  they  extend  3  or  4  miles 
into  this  county.  The  uplands  stand  150  to  200  feet  above  the  river  and 
are  generally  plane.  There  is,  however,  a  well-defined  drift  ridge  leading 
southward  from  Warsaw  a  short  distance  east  from  the  river  bluff,  a  ridge 
which,  as  previously  described,  apparently  marks  the  western  limit  of  the 
Illinois  glacial  lobe. 

The  thickness  of  the  drift  varies  greatlj^,  owing  to  the  presence  of  deep 
preglacial  valleys  which  haA^e  been  filled  to  a  level  as  great  as  the  border- 
ing: uplands.  In  such  valleys  rock  is  not  usuallv  entered  at  less  than  200 
feet,  but  on  the  bordering  uplands  it  may  be  entered  at  20  feet.  There  is 
usually,  however,  50  or  60  feet  of  drift  on  the  preglacial  uplands.  One  of 
the  most  conspicuous  of  these  buried  valleys  revealed  by  the  wells  is  found 
in  the  central  portion  of  the  count}-,  near  Carthage,  and  a  portion  of  its 
course  is  along  the  present  water  parting  between  the  Illinois  and  the  Mis- 
sissippi rivers.  This  valley  a^jparently  leads  southward  into  Adams  County 
along'  a  line  a  short  distance  east  of  the  A^alley  of  Bear  Creek.  Perhaps  its 
lower  course  is  followed  by  Bear  Creek. 

The  drift  is  mainly  a  compact  till,  and  in  places  wells  are  difficult  to 
obtain.     A  large  number  of  wells  have  been  sunk  to  a  depth  of  100  to  200 


682  THE  ILLINOIS  GLACIAL  LOBE, 

feet,  or  even  more,  many  of  them  entering  limestone  before  obtaining  a 
strong  vein  of  water. 

A  portion  of  the  lUinois-Mississippi  divide  is  fiat  and  poorly  drained, 
bnt  the  portions  of  the  county  adjacent  to  the  Mississippi,  and  also  to  Bear 
Creek  and  to  Crooked  Creek,  are  greatl)^  eroded. 

INDIVIDUAL    WrELLS. 

At  Dallas,  on  the  northern  border  of  the  county,  in  the  Mississippi 
Valley,  wells  are  usually  obtained  at  20  to  35  feet,  mainly  in  limestone. 
Occasionally  they  are  sunk  to  a  depth  of  150  feet. 

At  Nauvoo,  on  the  brow  of  the  Mississippi  blutf,  in  the  northwest  part 
of  the  county,  the  wells  are  usually  obtained  at  about  20  feet,  in  sand. 
Rock  is  entered  at  25  to  30  feet,  but  wells  seldom  reach  it. 

At  Laliarpe,  on  the  upland  plain,  in  the  northeast  part  of  the  county, 
the  strong  wells  are  obtained  in  sand  below  till  at  a  depth  of  about  60  feet. 
One  well  made  by  Mr.  Bainter  enters  rock  at  100  feet. 

In  the  vicinity  of  Webster  and  Fountain  Green,  in  the  east  part  of  the 
county,  wells  50  feet  in  depth  do  not  reach  rock.  They  are  mainly  through 
till.  Between  these  villages  and  Laharpe  there  is  an  area  of  several 
square  miles  in  which  the  rock  is  so  near  the  surface  that  sink  holes  abound. 

At  Carthage  the  public  water  supply  is  obtained  from  two  deep  wells, 
one  of  which  terminated  in  the  St.  Peter  sandstone  at  1,000  feet,  but  the 
other  continued  to  a  depth  of  1,700  feet.  AVater  veins  are  struck  in  the 
Niagara  limestone  at  about  750  feet;  in  the  Galena  limestone  at  865  feet, 
and  in  the  St.  Peter  sandstone  at  975  feet.  The  head  is  about  16  feet  below 
the  surface,  or  660  feet  above  tide.  The  water  is  rather  unpleasant  on 
account  of  salinity.  The  following  record  of  strata  penetrated  by  one  well 
before  reaching  the  St.  Peter  is  taken  from  the  Geology  of  Illinois:' 

Section  of  deep  tcell  at  Carthage,  Illinois. 

Feet. 

Drift,  clay,  sand,  and  gravel 214 

White  limestone 70 

Shale 355 

Limestone 336 

St.  Peter  sandstone,  penetrated 25 

Total  depth 1.  000 

At  Elvaston  wells  are  obtained  at  12  to  16  feet,  and  also  at  20  to  30 
feet,  from  beds  of  gravel  associated  with  till. 

'Vol.  VIII,  p.  65. 


WELLS  OF  HANCOCK  COUNTY,  ILLINOIS. 


683 


At  Hamilton,  on  the  brow  of  the  Mississippi  bluffs,  in  the  west  part  of 
the  county,  the  best  wells  are  obtained  in  the  rock,  which  is  entered  at  20 
or  30  feet.  Many  weak  wells,  however,  are  obtained  from  the  drift.  An 
artesian  well  has  been  sunk  at  Ringland's  Sanitarium,  in  the  north  part  of 
the  village.  It  has  a  depth  of  680  feet  and  obtains  a  flow  from  the  Lockport 
(Magara)  limestone,  which  is  penetrated  about  25  feet.  The  head  is 
reported  to  be  63  feet  above  the  surface,  or  aboxit  660  feet  above  tide. 

At  Warsaw  several  artesian  wells  have  been  sunk,  one  by  the  village 
and  others  by  corporations  and  private  individuals.  The  village  well  is 
mainly  for  fire  protection.  Gen.  Oliver  Edwards,  of  Warsaw,  has  furnished 
the  Survey  a  carefully  prepared  body  of  statistics  concerning  the  wells, 
and  these  statistics  are  presented  in  the  discussion  of  artesian  wells  in 
Illinois  appearing  in  the  Seventeenth  Annual  Report  of  this  Survey.  The 
wells  all  terminate  in  the  Galena  or  Trenton  limestone  and  have  depths 
ranging  from  750  to  860  feet.  The  original  head  at  each  of  the  wells  was 
about  680  feet  above  tide,  but  at  present  it  scarcely  exceeds  600  feet.  The 
water  is  sulphurous,  but  otherwise  not  of  unpleasant  quality. 

At  Plymouth,  in  the  eastern  part  of  the  county,  it  is  proposed  to  obtain 
a  public  water  supply  from  an  artesian  well.^ 

At  Augusta,  in  the  southeast  corner  of  the  county,  wells  are  usually 
obtained  in  sand  contained  in  the  di'ift,  at  depths  ranging  from  20  to  60 
feet.  A  few  have  been  drilled  into  the  underlying  Coal  Measures  to  depths 
ranging  from  120  to  265  feet. 

The  following  table  embraces  the  deepest  wells,  not  reported  in  the 
above  discussion,  of  which  records  were  collected.  They  are  confined 
mainly  to  the  southern  half  of  the  county : . 

Wells  in  Hancock  Cotmty. 


Owner  or  location. 

Altitude 
(above  tide). 

Depth. 

Kemarlis. 

Sec.  11,  T.  4,  R.  9  W 

Feet. 
645 

620 
625 

660 

Feet. 
73 

50 
80 

45 

Sec  12  T. 4  K  9W 

rock. 
Enters  rock  at  45  feet. 

Sec.  12,  T.  4,  R.  9  W 

No  rock ;  mainly  sandy  drift. 
Rock  entered  at  40  feet. 

Sec.  7.  T.  4.  R.  8  AV 

'Manual  of  American  Waterworks,  1897. 


684 


THE  ILLINOIS  GLACIAL  LOBE. 
Wells  in  Rancoclc  County — Coiitinued. 


Owner  or  location. 


Altitude       -n^^ti, 
(above tide).    ^^P''''- 


Remarks. 


W.  McCuen,  4   miles  south  of 
Hamilton. 

Sec.  30,  T.  4,  K.  8  W 

Sec.  31,  T.  4,  R.  8  W 

Sec.31,  T.4,R.8W 

Sntter  and  Vicinity 

Tioga  aud  vicinity 

J,  D.  Wood,  at  Chili 


Mr.    Cunningham,     2    miles 

northeast  of  Chili. 
Mr.  Dickersou,  2  miles  north 
of  Chili. 


Bowen  and  vicinity 

Owens's  mill  at  Still  well 

Sec.  1,  T.3,  R.7W 

Sec.  36,  T.  4,  R.  7  W 

East  part  T.  4,  R.  6  W 

Sec.  4,  T.  4,  R.  6  W 

Sees.  15  aud  16,  T.  4,  R.  6  W  . . . . 
Sec.  20,  T.  4,  R.  6  W 

Sec.29,T.4,  R.  6W 

Sec.  28,  T.  4,  R.  6  W 

Gittings  Mound,  north  line  of 
county- 


Feel. 
690 


750 
710 
750 

690 
700 

670 


670 


Feet. 


690 

670 
670 


74 


60 
63 

42 

40 
40 

70 


80 


220 


70 

217 
198 


660 

192 

660 

40 

670 

75 

680 

100 

690 

195 

700 

1,030 

700 

100 

750 

41 

Loess,  12  feet;  grayish-yellow  gummy  clay,  22  feet; 

blue  till,  8  feet;  peaty  soil  with  wood,  5  feet;  blue 

till,  28  feet. 
No  rock;  mainly  gray  till. 
Rock  entered  at  bottom. 
Surface  silt,  10  feet;  brown  clay,  few  pebbles,  15 

feet;  yellowish-gray  till,  17  feet. 
Rock  entered  at  about  25  feet. 
Surface  silt,  8  to  10  feet;  yellow  till,  20  to  25  feet; 

sand,  5  feet. 
Yellow  and  brown  clays,  15  feet;  gray  gummy  clay, 

10  feet;   yellowish-gray  till,  40  feet;   bard  blue 

till,  20  feet ;  rock  at  bottom. 
Two  wells  enter  rock  at  75  or  80  feet. 

Surfcice  silt,  6  feet;  grayish  gummy  clay  and  yellow 
till,  34  feet;  blue  clay  with  few  pebbles.  160  feet; 
gray  sand,  10  feet;  cemented  gravel,  5  feet;  loose 
gravel,  5  feet. 

Several  wells  enter  rock  at  65  or  70  feet ;  drift  mainly 
till. 

Rock  entered  at  207  feet. 

Yellowish  clays,  20  feet;  blue  clay,  175  feet;  sand, 
3  feet. 

Yellow  clay,  20  feet;  blue  clay,  168  feet;  sand  with 
wood,  4  feet. 

Rook  entered  at  30  or  40  feet. 

Rock  at  about  75  feet. 

Rock  struck  at  about  100  feet. 

Silt  and  yellow  clay,  26  feet;  blue  clay,  few  peb- 
bles, 169  feet;  sand  at  bottom,  6  feet. 

The  well  enters  rock  at  200  feet  aud  terminates  in 
St.  Peter  sandstone;  water  rises  to  40  feet  below 
surface. 

Rock  at  about  100  feet. 

Yellow  till,  30  feet;  blue  till,  11  feet;  sand  at  bot- 
tom. 


WELLS  OF  Mcdonough  county,  Illinois.  685 


Mcdonough   county, 
general  statement. 


McDonougli  County  is  situated  east  of  Hancock  and  has  an  area  of 
540  miles,  with  Macomb  as  the  county  seat.  The  county  is  drained  ahnost 
entirely  by  Crooked  Creek,  through  several  tributaries  leadiug  southwest- 
ward  to  that  stream.  The  surface  is  generally  much  eroded,  but  there  is  a 
flat  strip  on  the  north  and  east  borders  in  which  drainage  is  rather  imperfect. 
The  county  is  covered  to  a  depth  of  8  to  12  feet  or  more  with  a  j^orous 
sheet  of  loess  which  absorbs  water  rapidly  and  returns  it  to  the  crops  in 
seasons  of  drought. 

The  drift  is  composed  largely  of  a  compact  till,  and  in  places  strong 
wells  can  not  be  obtained  in  it.  Throughout  much  of  the  county,  however, 
the  wells  do  not  enter  the  rock.  There  is  apparently  a  general  coating  of 
50  to  75  feet  of  drift,  and  in  places  a  much  greater  depth.  In  the  extreme 
northeast  corner,  however,  near  Prairie  City,  the  rock  rises  in  ridges  slightly 
above  the  general  level  of  the  upland  plain. 


INDIVIDUAL    WELLS. 


At  Prairie  City  wells  on  the  rock  ridges  are  sunk  to  depths  of  50  feet 
or  more ;  those  on  the  plane  tracts  obtain  water  in  the  drift  at  20  to  30  feet. 

At  Bushnell  the  public  water  supply  is  obtained  from  a  well  115 
feet  in  depth  which  does  not  enter  rock.  A  well  at  the  Toledo,  Peoria  and 
Western  Railway  station  enters  rock  at  140  feet.  The  drift  consists  of 
about  20  feet  of  loess  and  yellow  till,  beneath  which  is  a  heavy  sheet  of 
blue  till.  Wells  are  obtained  from  thin  beds  of  sand  and  gravel  in  the  blue 
till,  or  occasionally  at  the  top  of  the  till. 

At  Macomb  the  public  water  supply  is  obtained  from  a  well  1,630  feet 
in  depth.  The  well  is  cased  to  the  St.  Peter  sandstone,  which  is  entered  at 
1,135  feet,  and  the  entire  supply  is  from  that  sandstone.  An  analysis  made 
by  this  Survey  is  published  in  the  Seventeenth  Annual  Report  (Part  II, 
pp.  925,  926).  The  water  is  moderately  hard,  but  its  chief  mineral  ingre- 
dients are  sodium  chloride  and  sodium  sulphate.  Some  dissatisfaction  with 
the  use  of  the  water  is  felt  because  of  these  ingredients,  though  the  quality 
is  similar  to  that  of  the  water  from  several  other  wells  in  use  in  western 
Illinois.     The  drift  at  Macomb  has  a  known  range  of  nearly  100  feet  in 


686  THE  ILLINOIS  GLACIAL  LOBE. 

depth.  The  deep  well  penetrates  145  feet,  hut  in  })arts  of  the  city  at 
similar  altitude  rock  is  entered  at  only  60  feet. 

At  Adair  the  wells  are  usually  25  or  30  feet  in  depth,  though  they 
occasionally  pass  into  the  rock,  which  is  entered  at  about  60  feet.  The  di-ift 
is  mainly  bkie  till,  which  is  entered  at  only  10  or  12  feet  from  the  surface. 

At  Good  Hope  the  village  well  is  33  feet  in  depth  and  has  the  follow- 
ing section,  reported  by  R^^  S.  D.  Peet : 

Section  of  town  well  at  Good  Hope,  Illinois. 

Feet. 

Loess 16 

Pebbly  brown  clay 2  or  3 

Saud  with  a  few  pebbles - 9 

Fine  sand  with  ferruginous  crust 2 

Blue  sand 2 

Blue  till 2 

Wells  in  tlie  vicinity  of  Good  Hope  enter  rock  at  depths  ranging  from 
45  to  8  b'  feet,  and  are  mainly  through  blue  till. 

FULTON   COUNTY. 
GENERAL    STATEMENT. 

Fulton  County  is  situated  east  of  McDonough  and  has  the  Illinois 
River  on  its  eastern  border.  The  area  is  870  square  miles,  and  Lewistown 
is  its  county  seat.  The  principal  stream  traversing  the  county  is  Spoon 
River,  which  passes  in  a  southward  course  through  its  western  part.  The 
surface,  like  that  of  the  adjoining  counties  on  the  north  and  west,  is  well 
di-ained.  In  addition  to  the  drainage  lines,  which  carrj-  oif  much  of  the  sur- 
plus rainfall,  there  is  a  capping  of  porous  loess  which  absorbs  a  lai-ge  part  of 
the  rain  and  returns  the  water  to  the  soil  in  seasons  of  drought. 

The  drift  is  in  thickness  similar  to  that  in  adjoining  counties.  An 
average  of  sections  on  the  uplands  reaching  rock  is  41  feet.  In  preglacial 
valleys  the  thickness  is  much  greater,  for  the  main  valleys  were  cut  to  a 
level  75  feet  or  more  below  the  low  water  of  the  present  Illinois.  The 
majority  of  wells  are  obtained  without  entering  the  rock,  there  being  a 
sufficient  amount  of  sand  and  gravel  interbedded  with  the  till  to  ailbrd 
a  strong  supply  of  water  for  wells. 


INDIVIDUAL    AVELLS. 


At  Farmington,  in  the  northeast  corner  of  the  county,  the  drift  is  only 
about  20  feet  in  thickness  and  wells  are  frequently  sunk  to  slight  depth  in 


WELLS  OF  FULTOK  COUNTY,  ILLINOIS.  687 

the  underlying  rock.  Similar  conditions  prevail  at  the  neig-hboring  village 
of  Fairview,  and  also  at  Avon,  in  the  northwest  part  of  the  county.  Fire 
protection  is  obtained  at  Avon  and  Farmington  by  pumping  from  wells  to 
tanks. 

The  city  of  Canton  obtains  its  public  water  supply  from  two  deep 
wells,  one  of  which  reaches  a  dej^th  of  2,500  feet  and  the  other  1,646  feet. 
The  latter  terminates  in  the  St.  Peter  sandstone,  but  the  former  may  reach 
the  Potsdam  sandstone.  Water  is  found  in  the  Gralena  limestone  at  1,100 
to  1,300  feet,  as  well  as  in  the  St.  Peter  sandstone  and  lower  strata.  The 
deeper  well,  with  a  diameter  of  but  4  inches,  has  an  estimated  capacity  of 
125  gallons  a  minute.  The  shallower  one,  with  a  diameter  of  6  inches,  will 
yield  260  gallons  a  minute.  The  former  well  is  cased  only  90  feet  and  has 
a  head  630  feet  above  tide,  or  about  30  feet  below  the  surface.  The  latter 
well  is  cased  797  feet  and  has  a  head  615  feet  above  tide,  which  is  15  feet 
above  the  surface,  this  well  being  located  on  ground  about  60  feet  lower 
than  the  other.  The  following  record  of  the  strata  penetrated  by  the  shal- 
lower well  was  published  in  a  Canton  paper  at  the  time  of  the  completion 

of  the  well: 

Section  of  a  deep  ivell  at  Canton,  Illinois. 

Feet. 

Surface 14 

Blue  shale 29 

Gray  shale 45 

Blue  shale 40 

Coal 1 

Fire  clay 6 

Blue  shale 35 

Gray  shale 22 

Coal 2 

Slate 12 

Shale 55 

Limestone,  sandstone,  and  shale 65 

Shale 15 

Black  limestone 7 

Limestone,  flint,  sandstone,  shale,  white  marl 192 

Shale 225 

Limestone 63 

Limestone  and  shale  (mixed ) 272 

Trenton  limestone  (water  bearing,  flow) 265 

Limestone,  sandstone,  shale,  etc 100 

St.  Peter  sandstone  (water  bearing,  flow) 241 J 

In  the  above  section  the  first  247  feet  of  rock  should  perhaps  be 
referred  to  the  Coal  Measures ;  the  next  279  feet  are  probably  Eocarbon- 
iferous  limestone,  shale,  etc. ;  the  following  heavy  bed  of  shale  (225  feet)  is 


688  THE  ILLINOIS  GLACIAL  LOBE. 

jDvesumably  Kinderhook;  the  next  335  feet  is  probably  to  be  referred  to 
the  Niagara  and  Hudson  river  formations ;  and  the  next  305  feet  to  the 
Galena  and  Trenton. 

The  public  water  supply  for  the  city  of  Lewistown  is  obtained  from  a 
series  of  wells  in  Spoon  River  Valley  about  20  feet  in  depth.  The  town  is 
situated  on  an  upland,  pi'obably  130  feet  above  the  river,  and  the  wells 
there  are  obtained  from  gravel  in  the  glacial  drift  at  a  depth  of  25  to  35 
feet. 

At  Astoria,  in  the  southern  part  of  the  coiinty,  wells  are  obtained  at 
20  to  40  feet  from  saud  below  till.  The  drift  in  that  vicinity  ranges  from 
30  to  70  feet  in  depth,  and  is  largely  till. 

At  Vermont,  on  the  west  border  of  the  county,  wells  are  usually 
obtained  at  25  to  35  feet.  The  drift  in  the  vicinity  of  that  village  is  about 
60  feet  in  depth.  A  test  boring  for  coal,  oil,  etc.,  was  made  at  this  village 
to  the  depth  of  2,487  feet,  which  probably  reached  the  Potsdam  sandstone, 
but  the  boring  is  not  utilized  for  water. 

At  Ipava  a  well  1,570  feet  in  depth  supplies  the  waterworks,  and 
is  used  also  by  a  woolen  mill.  A  sulpho -saline  water  was  struck,  pi-obably 
in  the  Galena,  at  a  depth  of  1,010  feet.  A  water  of  more  pleasant  taste  is 
obtained  from  the  St.  Peter  sandstone.  Strong  wells  are  obtained  in  the 
vicinity  of  this  village,  either  from  drift  or  from  rock,  at  about  100  feet. 

MASON    COUNTY. 
GENERAL    STATEMENT. 

Mason  County  is  situated  on  the  east  side  of  the  Illinois  River  opposite 
Fulton  County,  and  has  an  area  of  560  square  miles,  with  Havana  as  the 
county  seat.  The  county  occupies  a  low  basin-like  expansion  of  the  Illinois 
Valley,  heavily  covered  with  sand,  except  where  old  river  channels  have  left 
a  surface  deposit  of  muck.  The  drainage  is  imperfect,  and  extensive  arti- 
ficial ditching  has  been  necessary  to  render  the  old  river  channels  produc- 
tive. Much  of  the  county  is  so  sandy  that  it  is  not  cultivated.  The  eastern 
jiortion,  however,  is  very  fertile,  the  sand  there  being  a  fine  deposit  approxi- 
mating a  loess. 

The  thickness  of  tlie  drift  is  known  only  at  a  single  point — Mason — 
where  it  is  204  feet.  The  wells  are  usually  obtained  at  depths  of  20  to  40 
feet,  but  at  Havana  they  are  frequently  sunk  to  a  depth  of  70  feet,  through 
sand  and  gravel. 


WELLS  OF  MASON  COUNTY,  ILLINOIS.  689 

INDIYIDUAL   WELLS. 

At  Mason  the  wells  often  reach  a  depth  of  130  feet,  though  some 
water  can  be  obtahaed  at  35  feet.  A  prospect  boring  for  coal  at  this  town 
penetrated  the  following  complex  series  of  di-ift  deposits : 

Section  of  drift  beds  in  a  coal  boring  at  Mason,  Illinois. 

Ft.  In. 

Black  soil 5  o 

Yellow  cjay 30  0 

Yellow  Baud 5  0 

Gray  sand 32  7 

Blue  clay 1  o 

Fine  sand 23  11 

Hardpan 15  6 

Blue  clay _.. 7  0 

Sand 11  0 

Sand  and  gravel , 20  0 

Coarse  sand 10  0 

Sand  and  gravel 33  0 

Fine  red  sand _.  o  4 

Dark  sand ._ l  8 

Gravel  and  bowlders _ 5  4 

Sand 3  8 

Total  drift 204      0 

Several  beds  of  coal  were  passed  tlu-ough  in  the  underlying  Coal  Meas- 
ures, the  thickest  being  34  inches,  struck  at  a  depth  of  290  to  293  feet. 
The  rock  floor  at  this  well  is  394  feet  above  tide,  the  well  mouth  being 
598  feet. 

The  public  water  supply  at  the  city  of  Havana  is  reported  by  tlie 
Manual  of  American  Waterworks  to  be  obtained  from  10  driven  wells,  72 
feet  in  depth  and  6  inches  in  diameter. 

Near  San  Jose,  in  the  northeast  part  of  the  county,  wells  on  the  swampy 
land  are  obtained  at  about  30  feet.  They  penetrate  6  feet  or  more  of  black 
muck,  beneath  which  they  are  in  a  fine  blue  sand  to  near  the  bottom,  where 
gravel  is  struck.  On  the  higher  ground  east  from  San  Jose  wells  are  fre- 
quently sunk  to  a  depth  of  100  feet  or  more,  largely  through  sand  and 
gravel. 

TAZEWELL  COUNTY. 
GENERAL    STATEMENT. 

Tazewell  County  is  situated  northeast  of  Mason,  on  the  east  side  of  the 
Illinois  River,  and  has  an  area  of  650  square  miles,  with  Pekin  as  the 
county  seat.     The  county  is  traversed  nearly  centrally  from  east  to-  west  by 
MON  xxxviii 44: 


690  THE  ILLINOIS  GLACIAL  LOBE. 

Mackinaw  River,  wliicli  enters  the  Illinois  just  below  Pekin.  The  northern 
part  of  the  county  is  di'ained  by  Farm  Creek,  n'hich  enters  the  Illinois  oppo- 
site Peoria.  About  one-fourth  of  the  county  is  situated  in  the  Illinois  River 
valle\-,  in  the  northward  continuation  of  the  basin  referred  to  in  the  descrip- 
tion of  Mason  County.  The  uplands  have  an  extreme  altitude  of  about  450 
feet  above  the  Illinois  River  and  a  general  elevation  of  nearly  300  feet. 
The  Bloomington  morainic  system  crosses  the  northeast  part  of  the  county 
and  the  Shelbysalle  or  outer  moraine  of  the  AVisconsin  drift  leads  north- 
westward through  the  central  portion.  Between  these  moraines  there  is  a 
narrow  plane  tract  scarcely  5  miles  in  average  width.  The  portion  outside 
the  Wisconsin  drift  is  mainly  within  the  valley  of  the  Illinois  River,  but  a 
naiTOw  strijD  of  upland  is  found  between  the  moraine  and  river  bluff  south 
from  Pekin. 

There  are  rock  outcrops  at  a  few  points  along  the  east  bluff  of  the  Illi- 
nois River,  but  the  Avell  borings  distributed  widely  over  the  county  indicate 
that  the  drift  is  a  heavy  deposit.  Twenty  borings  wliich  do  not  reach  rock 
have  an  average  depth  of  135  feet,  while  four  which  reach  rock  penetrate 
an  average  thickness  of  247  feet  of  di-ift.  It  is  probable  that  the  aA'^erage 
for  the  countv  is  not  less  than  200  feet. 

In  the  Illinois  Valley  the  drift  is  largely  gravel  and  sand,  but  on  the 
uplands  there  is  a  heavy  sheet  of  soft  blue  till  deposited  at  the  Wisconsin 
stage  of  glaciation.  The  deep  wells  frequently  enter  a  hard  till  near  the 
bottom,  which  is  presumablv  the  deposit  of  an  earlier  stage  of  glaciation, 
and  contemporaneous  with  the  sheet  of  drift  found  outside  the  limits  of  the 
Wisconsin  drift.  Wells  are  often  obtained  at  depths  of  but  25  or  30  feet, 
and  the  depth  rarely  exceeds  75  feet. 

INDlVIDtTAL    WKLLS. 

Tlie  public  water  supph*  of  AVashingtou  is  obtained  from  wells  driven 
in  the  drift  to  a  depth  of  60  feet  or  more,  the  supply  coming  from  sand 
below  till.  This  sand  is  usually  entered  at  about  30  feet.  A  well  at 
Andrew's  mill,  in  AVashington,  227  feet  in  depth,  is  thought  to  have  entered 
z'ock  2  feet.  There  was  a  change  from  soft  to  hard  till  at  about  150  feet. 
A  well  at  the  Milburn  stock  farm,  near  AVashington,  23()  feet  in  depth,  did 
not  reach  rock.  It  was  mainly  through  till.  Some  intiaunnable  gas  was 
encountei'ed  near  the  bottom.     A  well  at  AA'illiam  Kiel's,  about  4  miles  west 


WELLS  OF  TAZEWELL  COUNTY,  ILLINOIS.  691 

of  Washington,  reciched  a  depth  of  262  feet  without  entering-  rock.  Several 
changes  in  structure  were  noted  during  the  boring. 

At  Morton  the  waterworks  well  is  230  feet  in  depth  and  terminates  in 
sand.  Three  other  wells  within  2  miles  northwest  reach  abont  the  same 
dejjth  without  entering  rock,  and  have  similar  sections.  The  waterworks 
well  is  reported  to  have  penetrated  30  feet  of  yellow  clay  and  sand  at  sur- 
face, beneath  which  was  70  feet  of  soft  blue  till,  belonging  apparently  to 
the  Shelby ville  drift  sheet.  The  next  100  feet  is  mainlv  a  hard  graA'  till, 
but  includes  about  20  feet  of  sand.     The  lower  30  feet  is  white  sand. 

At  Pekin  the  public  water  supply  is  obtained  from  the  g-ravel  of  the 
Illinois  River  Valley.  A  large  well,  50  feet,  in  diameter,  is  excavated  to  a 
depth  of  30  feet,  in  the  bottom  of  which  several  small  wells  are  driven  50 
feet  farther.  The  wells  will  yield  3,000,000  gallons  a  day.  Distilleries  at 
this  citv  use  the  Illinois  River  water.  An  artesian  well  sunk  on  a  high 
terrace  in  the  east  part  of  the  city  at  the  City  Park  reached  a  depth  of  850 
feet,  and  struck  salt  water  at  about  500  feet.  The  well  mouth  is  100  feet 
above  the  level  of  the  Illinois  River,  or  525  feet  above  tide,  and  a  flow  of 
water  is  obtained.  The  drift  is  about  200  feet  in  thickness.  '  Within  a  half 
mile  east  of  the  well  rock  is  exposed  in  the  bluff  at  an  altitude  25  feet  higher 
than  the  well  mouth. 

At  Delavan  the  public  water  supply  is  from  a  well  obtained  in  sand  and 
gravel  at  a  depth  of  160  feet.  A  well  was  sunk  by  this  village  to  a  depth 
of  241  feet  without  entering  rock,  and  penetrated  the  following  beds: 

Section  of  a  boring  at  Delavan,  Illinois. 

¥aet. 

Yellow  till 15 

Blue  till 60 

Black  muck  with  wood 6 

Greeu  mucky  clay , 8 

Gray  sandy  till 30 

Gray  sand 122 

Total  depth 241 

"  The  muck  found  beneath  the  blue  till  is  probably  at  the  base  of  the 
Wisconsin  drift  sheet.  A  well  4  miles  northeast  of  Delavan  at  an  altitude 
about  80  feet  above  the  village,  or  700  feet  above  tide,  struck  rock  at  a 
depth  of  313  feet.  The  drift  was  mainly  till  to  a  depth  of  140  feet,  and 
included  a  bed  of  black  muck  near  the  base.  The  remainder  of  the  sec- 
tion is  principally  sand,  as  at  Delavan. 


(392  THE  ILLINOIS  GLACIAL  LOBE. 

In  the  vicinity  of  Green  Valley  village,  on  the  portion  of  the  Illinois 
bottoms  northwest  from  Delavan,  several  wells  have  been  sunk  to  a  depth 
of  over  100  feet  through  sand  and  gravel  without  entering  rock.  In  one 
case  a  depth  of  145  feet  was  reached.  At  the  east  border  of  the  valley, 
however,  the  wells  in  some  cases  penetrate  40  to  60  feet  of  clay  before 
entering  sand  and  gravel.  One  in  sec.  6,  T.  22,  R.  4  W.  penetrated  60 
feet  of  clay,  then  75  feet  of  fine  sand,  and  obtained  water  in  the  gravel  at 
bottom.  Another  in  sec.  7  of  the  same  township  penetrated  62  feet  of  clay 
and  30  feet  of  sand,  when  a  water-bearing  gravel  was  struck. 

At  Hopedale  the  railway  well  is  195  feet  in  depth  without  reaching 
rock.  It  was  mainly  thi'ough  till  to  a  depth  of  160  feet,  beneath  which 
sand  was  encountered.  A  bed  of  black  muck  was  passed  tlu'ough  between 
till  sheets,  but  the  precise  depth  was  not  noted.  Between  Hopedale  and 
Armington,  a  well  on  the  farm  of  Robert  Pratt,  250  feet  in  depth,  is  thought 
to  have  struck  rock  at  the  bottom.  The  well  mouth  is  about  650  feet  above 
tide. 

At  Mackinaw  a  boring  160  feet  in  depth  was  mainly  through  till  to 
140  feet,  beneath  which  sand  was  entered  which  yields  an  inflammable  gas. 
Wells  at  this  village  usually  obtain  water  in  sand  and  gravel  between  till 
sheets  at  a  depth  of  35  or  40  feet.  The  waterworks  well  is  65  feet  deep, 
and  is  scarcely  adequate  to  supply  the  village. 

In  the  vicinity  of  Cooper,  on  the  crest  of  the  inner  strong  ridge  of  the 
Bloomington  morainic  system,  at  an  altitvide  about  820  feet  above  tide,  wells 
are  frequently  sunk  to  a  depth  of  150  feet,  mainly  through  till.  In  some 
wells  a  black  muck  is  found  between  tills  nearly  150  feet  below  the  surface. 


McLean  county, 
general  statement. 


McLean  County  is  situated  east  of  Tazewell,  with  Bloomington  as  the 
county  seat.  It  is  the  largest  county  in  the  State,  its  ai-ea  being  1,166 
square  miles.  The  northern  half  of  the  county  is  tributary  to  the  Mackinaw 
River,  with  the  exception  of  a  few  square  miles  in  the  northeast  corner, 
whicli  are  drained  northward  to  the  Illinois-Vermilion.  The  southern  half 
is  drained  by  the  Sangamon  and  its  tributaries.  The  valleys  are  all  small, 
within  tlic  limits  of  the  county,  and  in  many  cases  are  mere  ditches  cut  to 


WELLS  OF  MCLEAN  COUNTY,  ILLINOIS.  693 

a  depth  of  but  a  few  feet.  The  greater  part  of  the  county  is,  however, 
sufficiently  di-ained  to  need  but  Httle  artificial  ditching-. 

This  is  one  of  the  most  elevated  counties  in  central  Illinois,  mu'^h  of 
its  surface  being-  more  than  800  feet  above  tide  and  occasional  points  900 
feet.  The  northern  border  and  also  the  southwest  corner  fall  below  750  feet. 
A  very  small  area  in  the  southwest  corner  falls  below  700  feet. 

The  Bloomington  inorainic  system  traverses  the  county  neai-ly  centrally 
in  an  east-west  direction  and  occupies  a  Ijelt  6  to  10  miles  in  width.  The 
Mfickinaw  River  drains  its  north  border  and  the  Sangamon  and  tributaries 
its  south  border.  A  small  moraine,  Cropsey  Ridge,  follows  the  north  border 
of  the  Mackinaw  River  across  the  northeast  part  of  the  county,  separating 
this  drainage  system  from  the  Vermilion  drainage  system. 

The  di-ift  is  of  great  depth,  averaging  probably  over  200  feet.  Records 
of  ten  deep  borings  were  obtained  which  reach  rock  at  an  average  of  155 
feet,  but  twenty-one  others  have  an  average  depth  of  174  feet  without 
entering  rock.  The  drift  is  apparently  thinnest  in  the  northern  part  of  the 
county,  where  rock  is  struck  at  about  100  feet.  The  drift  in  the  central 
and  southern  portions  has  a  depth  of  200  to  250  feet.  Buried  soils  are 
found  at  two  or  more  horizons  at  depths  usually  of  100  feet  or  more,  but 
on  the  plain  outside  the  morainic  system  a  soil  occurs  at  40  feet  or  less. 
The  drift  above  the  first  buried  soil  is  usually  a  soft  blue  till.  At  greater 
depths  the  till  is  frequently  found  to  be  very  hard,  as  in  the  neighborino- 
counties  to  the  north  and  northeast,  already  discussed.  In  some  of  the  deep 
borings  a  large  amount  of  sand  and  gravel  is  found  in  the  lower  part  of  the 
di-ift.  Many  wells  have  been  sunk  to  a  depth  of  150  to  200  feet  in  order  to 
reach  the  water-bearing  beds  beneath  the  blue  till,  there  being  only  a  small 
amount  of  water-bearing  gravel  interbedded  with  the  blue  till. 

INDIVIDUAL   WELLS. 

At  Chenoa,  on  the  north  border  of  the  county,  several  strong  wells 
have  been  obtained  from  depths  of  100  to  150  feet  near  the  surface  of  the 
Coal  Measures  sandstone.  The  public  supply  is  from  two  wells  135  and 
214  feet  in  depth.^  Rock  is  entered  at  this  village  at  about  80  feet.  Wells 
from  the  drift  are  usually  weak  compared  with  those  from  the  rock. 


'  Manual  of  American  Waterworks,  1897. 


694  THE  ILLINOIS  GLACIAL  LOBE. 

The  Waterworks  Manual  reports  that  Lexington  has  its  public  svipj^ly 
from  a  well,  but  the  depth  is  not  given. 

At  Colfax  borings  for  coal  entered  rock  at  100  to  125  feet,  but  wells 
are  usually  obtained  at  moderate  depths,  seldom  exceeding  40  feet.  The 
drift  contains  considerable  sand  in  that  vicinity.  The  record  of  a  well 
about  4  miles  west  of  Colfax  shows  scarcely  any  till  in  a  depth  of  115  feet, 
at  rt'hich  depth  rock  was  entered. 

The  city  of  Bloomington  obtains  its  water  supplv  from  a  large  well  60 
feet  in  depth,  located  in  the  valley  of  Sugar  Creek.  The  well  penetrates 
about  33  feet  of  surface  gravel,  beneath  which  is  blue  clay  and  water- 
bearing gravel  at  60  to  65  feet.  Prospect  borings  show  a  belt  of  gravel 
about  2,000  feet  in  width  leading  down  the  creek  valley  from  the  vicinity 
of  the  waterworks.  Except  in  seasons  of  extreme  drought,  such  as  that  of 
1894  and  1895,  the  waterworks  well  can  be  depended  upon  to  furnish  an 
adequate  supply  for  the  city.  The  coal  shaft  near  the  Cliicago  and  Alton 
Railway  station,  at  an  altitude  of  about  750  feet,  entered  rock  at  a  depth  of 
161  feet,  penetrating  the  following  drift  beds: 

Section  of  drift  beds  in  a  coal  shaft  in  Bloomington,  Illinois. 

■Feet. 

Loam  and  gravel 20 

Blue  till <il 

Sand - 4 

Blue  till 76 

Total  drift 161 

In  Vol.  IV  of  the  Geology  of  Illinois  a  coal  shaft  at  Bloomington, 
one-half  mile  north  of  the  Chicago  and  Alton  Railway  station,  is  reported 
to  have  penetrated  252  feet  of  drift,  as  follows: 

Section  in  coal  shaft  one-half  mile  north  of  preceding. 

Feet. 

Brown  clay 10 

Blue  clay JO 

Gravelly  hanlpan 60 

Black  niolil  ^vitli  pieces  of  wood 13 

Hardpan  .ind  clay 89 

Black  mold .  6 

Bine  clay  34 

Sand,  bnfi'  ami  drab,  with  fossil  shells 2 

Total  drift 252 

A  well  in  the  east  part  of  Bloomington  14U  feet  in  depth  is  reported 
V)v  tlie  driller  to  liave  penetrated  a  "blue  i-ock"  the  lower  40  feet.     It  is 


WELLS  OF  MCLEAN  COUNTY,  ILLINOIS.  695 

possible,  however,  that  the  "bhie  rock"  is  only  a  hard  till.  A  well  at  the 
Soldiers'  Orphans'  Home  near  Bloomington  obtains  water  in  gravel  below 
till  at  130  feet. 

At  Ijeroy,  on  a  plain  south  of  the  Bloomington  morainic  system, 
strong  wells  are  obtained  in  sand  at  a  depth  of  20  or  30  feet.  In  the 
vicinity  of  the  village  wells  pass  through  a  black  muck  at  35  to  40  feet.  The 
public  water  supply  is  from  a  well  110  feet  in  depth  and  8  inches  in  diame- 
ter, which  will  yield  at  least  100  gallons  a  minute.  Many  wells  on  farms 
in  the  vicinity  of  Leroy  are  sunk  to  depths  of  76  or  100  feet,  and  occa- 
sionally 200  feet,  without  entering  rock,  and  the  water  rises  to  within  60  feet 
of  the  surface,  and  occasionall}-  within  10  feet.  A  prospect  boring  for  coal 
at  Leroy,  made  some  years  ago,  was  abandoned  at  a  depth  of  200  feet 
without  entering  rock. 

At  Saybrook,  in  the  eastern  part  of  the  county,  on  the  outer  slope  of 
the  Bloomington  morainic  system,  a  prospect  boring  for  coal  reached  rock 
at  247  feet.  It  was  mainly  through  till  for  38  feet,  then  mainly  sand  for 
67  feet,  beneath  which  was  100  feet  of  till,  which  was  in  turn  underlain  by 
62  feet  of  sandy  and  gravelly  drift. 

The  village  of  Danvers,  in  the  western  part  of  the  county,  has  recently 
put  in  a  waterworks  system  which  obtains  its  supply  from  a  well  about  200 
feet  in  depth  which  does  not  enter  rock.  The  creamery  well  at  Danvers  is 
also  about  200  feet  in  depth  without  entering  rock.  It  is  mainly  through 
till,  and  stnick  an  inflammable  gas  at  about  170  feet.  The  village  stands 
on  the  outer  ridge  of  the  Bloomington  morainic  system  at  an  altitude  slightly 
above  800  feet. 

In  the  vicinity  of  Shirley  and  Funk's  Grove  the  wells  are  reported  by 
Mr.  Lafayette  Funk  to  have  a  general  depth  of  only  30  or  40  feet,  and 
rarely  to  exceed  80  feet.  Water  is  obtained  in  gravel  below  till.  The 
village  well  at  Shirley  has  a  depth  of  40  feet,  but  a  neighboring  well  at  Mr. 
Douglas's  residence  reached  a  depth  of  75  feet. 

At  Hey  worth  the  general  depth  of  wells  is  30  to  40  feet,  abundance  of 
water  being  found  in  the  gravel  below  the  upper  sheet  of  till.  This  village 
has  sunk  borings  for  gas  which  reach  a  depth  of  166  to  300  feet.  Gas  is  found 
in  sand  at  155  to  166  feet  in  a  well  about  one-half  mile  south  of  the  villag-e, 
and  at  214  feet  in  a  well  three-fourths  of  a  mile  south  of  the  village.  A  well 
in  the  village  300  feet  in  depth  obtained  very  little  gas,  though  it  is  thought 


696 


THE  ILLINOIS  GLACIAL  LOBE. 


to  have  reached  the  rock.  The  callage  is  suppHed  with  gas  from  a  well 
southeast  of  it.  This  is  reported  by  the  owner,  J.  C.  Wakefiekl,  to  have  a 
pressure  of  22  pounds  to  the  square  inch  from  a  2-inch  pipe,  and  during 
the  winter  of  1896-97  it  supplied  fuel  for  200  stoves.  The  gas  may  be 
derived  in  part  from  underlying  Coal  Measures  shale,  but  muck  beds 
inclosed  in  the  drift  afford  a  probable  source.  A  section  of  the  drift  beds 
penetrated  appears  on  page  215. 

The  wells  in  the  following  table  are  the  deepest  of  which  records  were 
obtained,  and  include  but  a  small  part  of  those  which  have  been  sunk  in 
the  county.  There  is  probably  not  a  township  in  the  county  which  does 
not  include  several  wells  over  100  feet  in  depth. 

Wells  of  McLean  County. 


Owner  or  location. 

Altitude 
(above  tide). 

Depth. 

Remarks. 

Feel. 

Feet. 

Mr.  Helrterley,  near  Carlock  .. 

775 

210 

Three  beds  of  black  clay,  probably  soil,  the  lowest 
at  about  200  feet,  separated  by  till,  sand,   and 
gravel ;  upper  90  feet  of  -w-ell  entirely  till. 

Jacob   Shad,   3  miles  east  of 

800 

250 

Black  clay,  probably  soil,  at  about  150  feet. 

Carlock. 

Sec  31  T  24  R.  5  E 

850 

146 

Inflammable  gas  from  drift  at  bottom. 

Yellow   till,    15   feet;  soft  blue  till,  11   feet;  hard 

Sec  4  T  24  R.  4  E             .... 

775 

140 

KJ\>\^9    T,      J.    •    ^JTKj     -A^>    ^     J-J      ••«**•      ««rtvBa 

blue  till,  12  feet;  sand  and  gravel,  6  feet;  hard. 

blue  till,  40  feet;  soft  blue  till,  56  feet. 

Sec.  9,  T.  24,  R.  4  E 

775 

95 

Yellow  till,  15  feet ;   soft  blue  till,  65  feet :  hard 

sandy  blue  till,  15  feet. 

Sec.  28,  T.  24,  R.  4  E. 

850 

198 

Maiuly  till,  136  feet;  sand  and  gravel  with  gas,  62 
feet;  shale  at  bottom. 

Sec.  36,  T.  24,  R.  4  E 

850 

180 

Mainly  sand;  probably  rock  at  bottom. 

Sec  6  T  24  R.  4  E 

800 

230 

Yellow  till,  18  feet;  bine  till,  60  feet;  white  sand, 

KJ^\J9       Kff         J^     •       ■■    ''■J       -■-Vt       T.         -*-*        -•■•        ABB«        BBBH 

80  feet;  blue  sand,  .">0  feet;  gravel,  7  feet;  blue 

clay  to  bottom,  13  ieet. 

Sec.  21:1,  T.  24,  R.  1  W 

725 

256 

Loess  and  yellow  till,  12  feet ;  blue  clay  with  few 
pebbles,  244  feet;  gas  at  111  feet. 

Sec.  29,  T.  24,  R.  1  W 

725 

192 

Loess  and  yellow  till,  12  feet;  blue  clay,  few  jieb- 
bles,  95  feet;  hard  blue  till,  83  feet;  no  rock. 

Sec.  34,  T.  24,  R.  1  W 

725 

200 

Loess  and  yellow  till,  18  feet ;  soft  blue  till,  182  feet ; 
rook,  perhaps  a  bowlder,  at  bottom. 

Sec  2  T.23,R.1W 

725 

217 

Maiuly  blue  till;  gravel  at  bottom. 

Blue  till  entered  at  40  feet;  black  muck  with  wood 

Sec.  3,  T.  23,  R.  1  W 

725 

246 

and  leaves  at  about  200  feet. 

Mrs.  Cowdon,  at  (iilleiii 

S20 

116 

Mainly  blue  till;  gr.avel  at  bottom. 

WELLS  OF  VEEMILIOF  COUNTY,  ILLINOIS. 

Wells  of  McLean  County — Continued. 


697 


Owuer  or  location. 

Altitude 
(above  tide). 

Depth. 

Kemarks. 

Feet. 

Feet. 

E.  McGraw,  1  mile  east  of  Gil- 

825 

127 

Mainly  blue  till ;  gravel  at  bottom. 

lem. 

Southwest  part  T.  23,  E.  4  E . . . 

850 

187 

No  rock  struck. 

Sec.  7,  T.  22,  R.  4  E 

800 

176 

Yellow  silt  and  till,  15  feet;  soft  blue  1  ill,  24  feet; 

black  muck  with  wood,  4  feet ;  greenish  clay,  10 

feet;  gray  clay  and  sand,  8  feet;  blue- gray  till, 

113  feet. 

J.  Paiuter,  5  miles   north  of 

825 

190 

No  rock  struck. 

Le  Roy. 

H.Vert,  4  miles  north  of  LeEoy 

875 

221 

No  rock  struck. 

Leroy,  coal  boring 

778 

200 

Mainly  till,  56  feet;  sand,  145  feet;  no  rock. 
Gas  from  drift  at  about  100  feet. 

Sec  3  T.  22,  R  4  E 

850 
850 

100 
100 

4  miles  northeast  of  Ellsworth. 

Gas  from  drift  at  about  100  feet. 

VERMILION   COUNTY. 


GENERAL,    STATEMENT. 


Vermilion  County  is  situated  on  the  east  border  of  the  State,  about 
midway  of  the  east  line,  and  has  an  area  of  926  square  miles,  with  Danville 
as  the  count V  seat.  1 1  is  drained  naaiiily  by  Wabash- Vermilion  River,  whose 
North  Fork  leads  through  the  northeastern  part  of  the  county,  the  Middle 
Fork  through  the  northwestern,  and  Salt  Fork  through  the  western.  The 
south  border  of  the  county  is  drained  eastward  through  Little  Vermilion 
River  and  the  extreme  northwest  border  is  drained  northward  to  the 
Iroquois  River. 

The  north-central  portion  of  the  county  is  occupied  by  the  Blooming- 
ton  morainic  system,  which  is  here  differentiated  into  two  belts,  each  of 
which  in  places  presents  a  double  ridge.  The  south  border  of  the  county  is 
traversed  by  the  Champaign  morainic  system,  whose  main  ridge  lies  south 
of  Little  Vermilion  River,  but  which  has  a  minor  ridge  leading  eastward 
across  the  county  a  few  miles  farther  north  than  this  stream. 

In  the  southern  half  of  the  county  the  drift  is  generally  of  shallow 
depth,  rock  being  entered  frequently  at  30  or  40  feet,  or  even  less.  In  the 
northern  half  of  the  county  the  thickness  is  much  greater.  The  few  bor- 
ings  of  which  records  were  obtained  indicate  that  it  may  averag'e  not  less 


698  THE  ILLINOIS  GLACIAL  LOBE. 

than  200  feet.  The  elevation  of  the  northern  portion  is  greater  than  tlie 
southern,  but  not  so  much  as  the  difference  in  the  thickness  of  drift,  being- 
perhaps  50  or  75  feet  g-reater. 

In  the  northern  half,  where  the  drift  is  thick,  the  sti-ucture  is  similar  to 
that  of  Iroquois  County,  which  borders  it  on  the  north;  there  being  a  soft 
blue  till  about  100  feet  in  thickness  along  the  moraines,  and  of  somewhat 
less  depth  on  the  narrow  plains  between  them.  Beneath  this  till  tliere  is 
frequently  a  black  muck  or  soil,  under  which  a  harder  till  sheet  sets  in.  In 
places  the  lower  portion  of  the  drift  is  sand  or  gravel  instead  of  hard  till. 
In  the  southei-n  part  of  the  county,  where  the  drift  is  comparativelv  thin,  it 
consists  of  soft  till  similar  to  the  surface  portion  in  the  district  to  the  north. 
The  older  sheets  of  drift  are  apparently  present  only  in  thin  deposits. 

Many  flowing  wells  have  been  obtained  in  the  valley  of  Middle  Fork, 
near  Potomac.  J.  M.  Crayton,  in  a  letter  addi-essed  to  the  Director,  February 
3,  1897,  reported  that  within  a  square  mile  in  the  vicinity  of  Potomac  there 
are  over  200  flowing  wells,  varying  in  depth  from  65  to  140  feet,  each 
throwing  a  continuous  and  never-failing  2-incli  stream  of  j^alatable  water. 
The  water  is  obtained  from  beds  of  sand  below  blue  till,  and  there  are 
tln-ee  or  more  water-bearing  beds,  separated  by  thin  beds  of  till  or  clay. 
The  wells  situated  on  low  tracts  between  morainic  ridges  in  this  county 
have  generally  a  strong  hj^drostatic  pressm-e,  with  head  but  a  few  feet  lielow 
the  surface.  The  absorbing  area  is,  in  all  probability,  on  the  neighboring- 
moraine.  The  sheets  of  drift  are  usually  so  arranged  that  water  absorbed 
by  a  moraine  may  readily  pass  northward  beneath  the  neighboring-  till  plain. 
In  the  southern  portion  of  the  county  there  is  also  some  rise  in  tlie  wells, 
especially  if  made  on  slopes  north  of  the  moraines.  The  wells  there  ai'e, 
however,  shallower  than  in  the  northern  portion  of  the  county,  and  condi- 
tions are,  on  the  whole,  less  favorable  for  obtaining  flowing  wells. 

INDIVIDUAL    WELLS 

The  ])ublic  water  supply  of  Hoopeston  is  from  a  well  350  feet  in 
depth,  which  enters  rock  only  50  feet.  The  upper  30  feet  of  the  drift  is 
clay  and  sand,  the  remainder  principally  gravel.  The  well  is  only  8  inches 
in  diameter,  yet  in  1895  it  had  an  estimated  capacity  of  2,000,000  gallons 
a  day.  'I'lie  liead  is  about  20  feet  Iw'low  tlie  surface.  The  water  is  inod- 
erately  liard,  and  has  a  small  amount  of  sulpliate  of  sodium  and  a  still 
smaller   amount    of  sulphate   of  magnesium,    l)ut    is    very    palatalilc      The 


WELLS  OF  VERMILION  COUNTY .  ILLINOIS.  699 

Manual  of  American  Waterworks  (1897)  reports  two  8-inch  driven  wells  at 
the  waterworks.  Many  wells  are  obtained  in  the  vicinity  of  Hoopeston  at 
depths  of  80  to  100  feet,  in  sand  or  gravel  below  blue  till. 

At  East  Lynn  wells  are  usnally  obtained  at  depths  of  40  to  60  feet,  in 
gravel  or  sand  below  a  sheet  of  till. 

At  Rossville  a  coal  boring  about  500  feet  in  depth  entered  hard  rock 
at  190  feet.  There  is  125  feet  of  blue  till  forming-  the  upper  part  of  the 
drift,  beneath  which  is  60  feet  of  cemented  material,  called  by  the  driller  a 
soft  sandstone,  under  which  there  is  a  water-bearing  gravel  resting  on  the 
rock.  A  similar  cemented  material  was  penetrated  in  a  boring  about  5 
miles  north  of  Rossville.  It  sets  in  under  the  blue  till  at  a  depth  of  150 
feet,  and  is  underlaid  by  a  yellow,  pebbly  clay,  extending  to  the  rock  at 
235  feet.  The  Manual  of  American  Waterworks  reports  that  the  public 
supply  at  Rossville  is  from  a  deep  well. 

The  public  water  supply  for  the  city  of  Danville  is  pumped  from  the 
North  Fork  of  Vernjilion  River.  Wells  in  the  city  usually  enter  rock  at  a 
depth  of  about  15  feet  and  obtain  water  at  a  depth  of  60  to  75  feet,  which 
is  near  the  level  of  the  Vermilion  River.  A  deep  well  sunk  at  Dan- 
ville Junction  to  a  depth  of  2,008  feet  has  the  following  section,  reported 
by  J.  Gr.  English,  of  Danville:  ' 

Section  of  a  well  at  Danville  Junction,  Illinois. 

Feet. 

Yellow  till  and  gravel 20 

Blue  till 15 

Hardpan 30 

Blue  till '. 15 

Sandy  loam  10 

Clay,  sand,  and  gravel 1 50 

Muck  bed  -svitli  wood • 8 

Tough  blue  clay - 25 

Sand  and  gravel 2 

Coal  Measures  and  Devonian  strata 950 

Hard  gray  limestone  (probably  Upper  Silurian). 51 

Soft  gray  limestone  with  H:S  gas 10 

Limestone,  both  dark  and  light  colored 160 

Soft  white  limestone  with  US  gas 12 

Limestone,  both  dark  and  light  colored 342 

AVhite  sandstone  (St.  Peterf),  and  brackish  water 35 

Clay  shale 110 

Gray  limestone 125 

Blue  limestone - 65 

Blue  shale 57 

Eed  rock 15 

Total  depth 2,008 


700  THE  ILLINOIS  GLACIAL  LOBE. 

A  well  near  tlie  waterworks  in  the  Vermilion  Valler  penetrated  to 
sup230sed  Upper  Silnrian  limestone,  which  it  enters  at  a  deptli  of  1,075 
feet.  Tlie  thickness  of  drift  at  the  Danville  Junction  well  much  exceeds 
that  of  other  wells  in  the  neighborhood,  and  indicates  that  a  preglacial 
valley  was  entered  by  the  boring. 

At  Fithian,  in  the  western  part  of  the  county,  wells  are  usuallv  obtained 
from  sand  or  gravel  associated  with  the  till  at  depths  of  50  feet  or  less,  but 
one  well  was  found  to  have  a  depth  of  90  feet,  of  whicli  the  lower  15  feet 
is  in  rock. 

At  Fairmount  rock  is  entered,  at  slight  depth,  and  wells  usually  are 
obtained  at  less  than  50  feet. 

At  Indianola  wells  are  obtained  from  sand  or  gravel  below  till  at  a 
depth  of  about  30  feet,  a  strong  supply  of  water  being  found  at  this  depth. 

At  the  village  of  Ridge  Farm  the  wells  are  usually  obtained  at  a  depth 
of  20  feet  or  less,  in  sand  associated  with  till. 

The  flowing-  wells  near  Potomac,  in  the  north  part  of  the  county, 
referred  to  above,  usually  penetrate  the  following-  series  of  drift  beds,  the 
section  being  furnished  by  George  Piatt,  a  well  driller  who  has  sunk  sev- 
eral of  the  wells : 

Generalized  section  ofjioiriny  irells  near  Potomac,  Illinois. 

Feet. 

Yellow  pebbly  clay  (Wisconsin) 10-  12 

Blue  clay,  soft  like  putty,  and  containing  few  pebbles  (^Wisconsin) 60-  70 

Hard,  stony  clay,  or  ferruginous  crust 1-    3 

Sand  and  gravel,  witb  artesian  water 6-  10 

Hard,  partially  cemented,  sandy  clay 25-  30 

Sand  and  gravel,  with  artesian  water 5 

1  lard,  partialU'  cemented,  sandy  clay •. 1.5-  20 

Sand  and  gravel,  with  artesian  water several  feet 

Very  few  records  of  deep  wells  were  obtained  in  this  couutv  outside 
the  villages  just  discussed.  The  record  of  a  farm  well,  made  in  sec.  31, 
T.  23,  R.  13  W.,  shows  240  feet  of  drift,  mainly  till  of  a  blue  color,  at  the 
bottom  of  wliicli  water  was  obtained  in  sand  and  gravel.  A  well  in  sec.  3G, 
in  the  same  township,  penetrated  drift  a  deptli  of  160  feet  without  reaching 
rock,  and  a  well  near  Alviu  a  deptli  of  173  feet. 


WELLS  OF  CHAMPAIGN  COUNTY,  ILLINOIS.  ■  701 


CHAMPAIGN  COUNTY. 
GENERAL    STATEMENT. 


Champaign  County  is  situated  west  of  Vermilion,  aiid  has  an  area  of 
1,000  square  miles,  with  Urbana  as  the  county  seat.  The  eastern  and 
northeastern  portions  are  tributary  to  the  Vermilion  River.  The  southern 
portion  contains  the  headwaters  of  the  Embarras  and  Kaskaskia  rivers,  and 
the  northwestern  portion  is  crossed  by  the  Sangamon  River.  Much  of  the 
surface  is  so  level  that  artificial  ditching  has  been  necessary  to  give  good 
drainage.  There  are,  however,  two  morainic  systems  crossing  the  county. 
The  outer  belt  of  the  Bloomington  system  crosses  the  northeast  corner,  while 
the  Champaign  morainic  system  traverses  the  county  in  a  southeast  course, 
a  little  to  the  south  of  the  center.  The  latter  system  consists  of  tlu-ee  dis- 
tinct ridges  in  the  southeast  part  of  the  county,  which  become  united  into  a 
single  ridge  near  Champaign,  and  continue  united  to  southeastern  McLean 
Countv,  beyond  which  the  morainic  system  is  not  traceable.  The  belt 
belonging  to  the  Bloomington  system  has  an  ave:;ige  relief  of  about  50  feet 
above  the  plain  bordering  it  on  the  southwest.  The  Champaign  morainic 
system  has  even  less  average  relief  above  the  bordering  plains. 

In  the  portion  of  the  county  southeast  from  Urbana  the  drift  has  an 
average  thickness  of  scarcely  100  feet,  but  throughout  the  remainder  of  the 
coiTuty  its  thickness  is  much  greater.  Records  of  22  borings  which  did  not 
reach  rock  show  an  average  of  171  feet,  and  it  is  probable  that  the  average 
for  the  county  is  not  less  than  200  feet.  The  drift  to  a  depth  of  about  100 
feet  is,  in  the  main,  a  soft  blue  till  of  Wisconsin  age.  On  the  moraines  the 
depth  is  correspondingly  greater.  Prof  C.  W.  Rolfe,  of  the  University  of 
Illinois,  reports  that  throughout  much  of  the  county  wells  are  found  to 
pass  through  a  buried  soil  immediately  below  the  blue  till,  and  then  to 
enter  a  harder  till.  The  writer  found  exposures,  of  which  desci-iption  has 
already  been  given  (p.  216),  of  a  peaty  muck  or  soil  along  the  bluffs  of 
the  Sangamon  River  in  the  western  part  of  the  county. 

Many  wells  have  been  sunk  through  the  blue  till  into  beds  of  sand  or 
gravel  associated  with  the  underlying  harder  till,  as  shown  in  the  discussion 
below.  Throughout  much  of  the  county  the  wells  have  strong  hydrostatic 
pressure,  though  they  seldom  overflow. 


702  THE  ILLINOIS  GLACIAL  LOBE. 

INDIVIDTAL    ^VELLS. 

In  the  \acinity  of  Ludlow,  in  the  north  part  of  the  countv,  at  an 
ahitude  about  800  feet  above  tide,  several  wells  have  been  sunk  to  a 
depth  of  150  feet  without  reaching  rock.     They  are  largely  through  till. 

A  well  at  F.  Delaney's  near  Dickerson,  in  the  northwest  part  of  the 
countv,  at  an  altitude  about  750  feet  above  tide,  reached  a  depth  of  280 
feet  without  encountering  rock. 

In  the  vicinity  of  Rantoul  the  wells  range  from  80  to  200  feet  in  di-ift. 
The  public  water  supply  for  this  village  is  obtained  from  a  well  135  feet  in 
depth,  mainly  through  blue  till.  A  prosjDect  boring  for  coal  at  this  village, 
reported  in  the  Geology  of  Illinois,  is  said  to  have  reached  rock  at  a  depth 
of  80  feet.  The  report,  however,  is  based  upon  rather  imperfectly  sup- 
ported data,  the  results  of  the  boring  having  been  kept  secret  for  about 
twelve  years  before  they  were  communicated  to  the  Survey.^ 

Near  Gilford,  in  the  northeast  part  of  the  county,  on  the  crest  of  the 
outer  ridge  of  the  Bloomington  morainic  system,  a  well  is  reported  to  have 
reached  a  depth  of  260  feet  and  little  or  no  rock  was  penetrated.  No 
more  definite  record  of  the  well  was  obtainable. 

In  the  vicinitv  of  ]\Iavview  several  wells  have  been  obtained  in  sand 
and  gravel  below  till  at  depths  of  80  to  100  feet.  A  well  at  the  residence 
of  T.  Hissong  in  Mayview  reached  a  depth  of  118  feet. 

The  cities  of  Champaign  and  Urbana  have  a  common  public  water 
supply  obtained  from  seven  wells  sunk  to  depths  of  157  to  162  feet  in  the 
glacial  drift.  The  combined  daily  capacity  of  tlie  wells  is  nearly  a  million 
gallons.  The  wells  range  in  diameter  from  5  to  8  inches.  Two  coal  bor- 
ings  at  Urbana  show  a  difterence  of  165  feet  in  the  distance  to  rock,  one 
enteriny-  rock  at  100  feet,  the  other  at  265  feet.  The  tbift  section  of  the 
deeper  one,  furnished  by  Prof  C  W.  Rolfe,  appears  on  page  235. 

At  Champaign  a  deep  boring  prospecting-  for  coal  and  gas,  as  indi- 
cated in  the  section  on  page  234,  has  penetrated  a  deposit  of  drift  even 
thicker  than  in  the  deepest  boring  at  Urbana,  it  being  300  feet,  but  the 
altitude  is  aljout  30  feet  higher  than  at  the  Urbana  boring,  thus  giving  the 
rock  surface  nearh'  tlie  same  altitude  at  l)()tli  })laces. 

At  .Sidne\'  the  duy  wells  are  about  30  feet  and  bored  wells  30  to  70 


'Geology  of  Illinois.  Vol.  IV,  p. 274. 


A¥ELLS  OF  PIATT  COUNTY,  ILLINOIS.  703 

feet  in  depth,  water  being  obtained  in  beds  of  sand  and  gravel  associated 
with  till.  A  prospect  boring  for  coal  at  this  village  entered  rock  at  95  feet. 
The  section  of  the  drift  penetrated  appears  on  page  236. 

In  the  vicinity  of  Homer  wells  are  usually  obtained  at  about  30  feet, 
and  rock  is  entered  at  90  feet.  South  from  Homer,  near  the  southeast 
corner  of  the  county,  wells  are  usually  obtained  at  20  to  40  feet,  but  occa- 
sionally reach  a  depth  of  lOO  feet  without  entering  rock. 

At  the  village  of  Philo,  which  is  situated  on  the  crest  of  one  of  the 
ridges  of  the  Champaign  system,  a  well  reached  a  depth  of  171  feet  with- 
out entering  rock  (see  p.  235). 

Several  wells  in  the  vicinity  of  Philo  reach  a  depth  of  100  feet  without 
entering  rock. 

At  Mahomet  several  wells  obtain  water  at  45  to  50  feet.  A  well  in 
this  callage  at  D.  McArtlmr's  has  the  following  section: 

Section  of  McArthur  well  at  Mahomet,  Illinois. 

Feet. 

Gravel <■ 7 

Pebbleless  clay 3 

Browu  mid  gray  till - 32 

Black  muck 2 

Hard  till 58 

Total  depth 100 

A  well  at  Jonas  Lester's,  a  half  mile  south  of  Mahomet,  passes  tlu-ough 
a  black  soil  below  till  at  about  36  feet.  The  section  of  an  exposure  in 
the  Sangamon  bluff  south  from  Mi-.  Lester's  appears  on  page  216. 

A  well  at  George  Frankenburgher's,  2  miles  east  of  Mahomet,  at  an 
altitude  60  feet  higher  than  the  village,  reached  a  depth  of  200  feet  with- 
out entering  rock.  About  4  miles  southwest  from  Mahomet,  on  ground 
no  higher  than  the  village,  records  of  three  wells  were  obtained  which 
penetrate  over  200  feet  of  drift,  mainly  blue  till,  without  entering-  rock 
(see  pp.  219-220). 

PIATT  COUNTY. 
GENERAL    STATEMENT. 

Piatt  County  is  situated  in  the  east-central  part  of  the  State,  immedi- 
ately west  of  Champaign  County,  and  has  an  area  of  440  square  miles, 
with  Monticello  as  the  county  seat.  The  Sangamon  River  leads  southwest- 
ward  through  the  central  portion  of  the  county,  and  is  the  onl3^  stream  of 


704  '  THE  ILLINOIS  GLACIAL  LOBE. 

importance  within  its  limits.     Mnch  of  the  county  has  a  very  level  surface 
which  requires  artificial  di'ainage. 

Tlie  few  borhig-s  of  which  records  were  obtained  indicate  that  the 
county  is  covered  with  a  very  thick  sheet  of  drift,  averaging  probably  more 
than  200  feet.  The  greater  part  of  the  drift  appears  to  be  blue  till.  Shal- 
low wells  of  moderate  streng'th  are  often  obtained  at  depths  of  25  to  40 
feet,  but  tubular  wells  are  usually  sunk  to  depths  of  100  feet  or  more  and 
obtain  stronger  supplies  than  at  shallow  depths. 

INDIVIDUAL    WELLS. 

At  Monticello  the  public  water  supply,  as  noted  on  page  220,  is  from 
two  wells  212  and  316  feet  in  depth,  neither  of  which  entei's  rock. 

At  Bement  the  public  water  supply  is  obtained  from  two  wells,  one  138 
feet,  in  gravel  below  till,  the  other  225  feet,  in  rock  the  lower  3  feet.  The 
shallower  one  obtains  the  larger  supply  of  water.  The  Wabash  Railway 
has  a  strong  well  at  this  village  152  feet  in  depth,  from  gravel  below  till. 
A  well  at  the  mill,  141  feet  in  depth,  is  also  in  gravel  below  till.  Joseph 
Rodman  sunk  a  well  to  a  depth  of  384  feet,  which  entered  rock  at  205 
feet.  A  well  at  the  Bement  cemetery,  2  miles  north  of  the  village,  at  an 
altitude  about  45  feet  higher,  reached  a  depth  of  221  feet  without  entering 
rock,  and  a  well  one-half  mile  east  of  the  cemetery,  222  feet  in  depth,  did 
not  reach  rock. 

At  Cerro  Grordo  several  wells  have  been  sunk  to  a  depth  of  about  1^0 
feet  without  reaching  rock.  The}^  are  mainly  through  blue  till,  and  in 
some  cases  are  rather  weak. 

A  well  near  Mansfield,  on  the  farm  of  Mrs.  R.  Carson,  as  noted  on 
page  234,  reached  a  depth  of   200    feet   without  entering  rock,  mainly, 
through  sand. 

DE^A^ITT   COUNTY. 
GENERAL    STATEMENT. 

Dewitt  County  is  situated  in  the  central  part  of  the  State,  west  of  the 
northern  portion  of  Piatt  Countv,  and  south  of  McLean  County.  It  has  an 
area  of  405  square  miles,  and  Clinton  is  the  county  seat.  Salt  Creek,  a 
tributary  of  the  Sangamon  River,  leads  westward  through  the  central  por- 
tion of  the  county,  and  is  the  main  stream  within  its  limits.     The  western 


WELLS  OF  DEWITT  COUNTY,  ILLINOIS.        '  705 

part  of  the  county  is  traversed  by  the  outer  moraine  of  the  Wisconsin  drift 
sheet,  which  here  has  a  relief  of  nearly  100  feet  above  the  plain  to  the 
west,  but  rises  only  a  few  feet  above  the  plain  to  the  east. 

The  drift  of  this  county,  like  that  of  the  neighboring-  counties,  Piatt 
and  McLean,  is  very  heavy,  averaging-  probably  more  than  200  feet.  The 
upper  100  feet  is  mainly  a  blue  till,  except  on  the  plain  outside  the  Wiscon- 
sin drift,  where  much  sand  and  gravel  occiu-s.  The  few  deep  wells  sunk  on 
the  newer  drift  indicate  that  the  sandy  drift  continues  eastward  under  the 
Wisconsin  drift  sheet.  In  several  places  buried  soils,  or  muck  beds,  have 
been  found  about  the  leVel  of  the  base  of  the  Wisconsin  drift.  There  are 
also  numerous  instances  of  inflammable  gas  from  beds  of  sand  and  gravel 
in  the  drift. 

INDIVIDUAL   WELLS. 

But  few  records  of  wells  have  been  obtained  in  this  county,  and  these 
are  of  considerable  depth.  Wells  are  often  obtained  at  moderate  depths  in 
sand  or  gravel  associated  with  the  blue  till. 

At  Farmer  City  the  public  water  supply  is  from  a  well  176  feet  in 
depth,  which  terminates  in  sand.  The  head  is  now  a  few  feet  below  the 
surface,  but  when  first  made  the  well  ovei-flowed.  A  prospect  boring  for 
coal  at  this  town  entered  rock  at  a  depth  of  189  feet.  The  upper  half  of 
the  drift  is  mainly  till,  the  lower  half  largely  sand  and  gravel.  (See  section 
on  page  216.) 

A  well  one  mile  noi-th  of  Parnell,  200  feet  in  depth,  did  not  enter  the 
rock. 

At  Clinton  strong  wells  are  obtained  from  sand  and  gravel  below  till 
at  depths  of  80  to  110  feet.  The  public  water  supply  is  obtained  from 
several  wells  about  110  feet  in  depth.  The  following  detailed  record  of  the 
drift  penetrated  at  Clinton,  in  a  prospect  boring  for  coal,  made  with  a 
diamond  di-ill,  is  taken  from  the  Geology  of  Illuiois:^ 

Drift  heds  in  a  prospect  boring  for  coal  at  Clinton,  Illinois. 

Feet. 

Surface  soil 5 

Quicksand 15 

Saud  with  gravel  aud  bowlders 17 

Sand  and  clay  mixed 53 

Hardpan 12 

Gravel '. 1 1  . 

Hardpan  ...^ 4 

>  Vol.  VIII,  p.  34. 
MON   XXSVIII 45 


706  THE  ILLINOIS  GLACIAL  LOBE. 

Feet. 

Clay  and  sand i 

Gravel  and  clay 7 

Hardpan 3 

Clay  and  sand 7 

Clay  and  gravel 14 

Clay 4 

Hardpan 6 

Clay  and  gravel 8 

Quicksand 5 

Sand  and  gravel 2 

Coarse  gravel 2 

Clay 6 

Gravelly  hardpan 25 

Quicksand 6 

Sand  and  clay 7 

Gravel 9 

Sand 11 

Gravel 9 

Sand 9 

Quicksand  and  gravel 101 

Total  depth  (if  drift 352 

This  boring'  continued  to  a  depth  of  942  feet  without  reaching  the  bot- 
tom of  the  Coal  Measures.  A  boring  about  one-half  mile  farther  north  was 
carried  to  a  depth  of  539  feet  and  penetrated  only  270  feet  of  drift,  or  70 
feet  less  than  that  whose  section  is  just  given. 

The  section  of  a  gas  well  at  James  Barnett's,  8  miles  west  of  Clinton, 
also  reported  in  the  Greology  of  Illinois,  appears  on  page  205.  It  is  stated 
that  dry  sand  and  pebbles  were  thrown  out  upon  the  surface  by  the  pressure 
of  the  gas  which  was  struck  at  the  bottom  of  this  well. 

In  the  -sacinity  of  Hallsville  several  gas  wells  have  been  obtained  from 
beds  of  gravel  between  sheets  of  till  at  a  depth  of  117  to  127  feet.  The  gas 
is  used  in  some  cases  to  supply  light  and  fuel  for  dwellings. 

At  Kenney,  on  the  low  plain  outside  the  Wisconsin  drift  sheet,  at  an 
altitude  only  650  feet  above  tide,  a  boring  was  sunk  to  a  dejstli  of  291  feet, 
mainly  through  sand  and  gravel,  without  reaching  the  rock. 

At  Waynesville,  in  the  northwest  comer  of  the  count}-,  on  the  outer 
slope  of  the  moraine  which  marks  the  limit  of  the  Wisconsin  drift,  the  public 
water  supply  is  obtained  from  wells  150  feet  in  depth.^ 

In  the  vicinity  of  Wapella  wells  seldom  obtain  a  good  supply  of  water 
at  less  than  65  feet,  and  several  are  80  to  100  feet  iu  depth.  They  penetrate 
only  8  to  12  feet  of  surface  silt  and  yellow  till  before  entering  blue  till. 

'  See  Manual  of  American  Waterworks,  1897 


WELLS  OF  LOGAN  COUNTY,  ILLINOIS.  707 

The  blue  till  extends  to  about  80  feet.  At  this  depth  a  black  mucky  soil 
containing  wood  is  found,  which  is  underlain  by  a  green  clay,  apparently  a 
swamp  subsoil.  The  muck  and  associated  green  clay  are  often  several  feet 
in  thickness.  They  rest  upon  a  harder  till  than  that  which  overlies  them. 
Occasionally  gas  is  struck  in  sand  near  the  level  of  the  buried  muck,  but 
not  in  sufficient  amount  to  be  utilized  for  fuel. 

LOGAN  COUNTY. 
GENERAL  STATEMENT. 

Logan  County  is  situated  in  the  central  part  of  the  State,  with  Lincoln 
as  the  county  seat,  and  has  an  area  of  620  square  miles.  It  is  drained  by 
Salt  Creek  and  its  tributaries,  the  principal  tributaries  being  Sugar  Creek, 
Kickapoo  Creek,  and  Lake  Fork.  With  the  exception  of  the  northeast 
corner,  it  lies  outside  the  limits  of  the  Wisconsin  drift  and  its  drainage  sys- 
tems are  much  more  mature  than  those  on  the  Wisconsin  di'ift  to  the  east, 
though  the  elevation  is  about  100  feet  lower  than  on  neighboring  portions 
of  the  Wisconsin  drift.  In  addition  to  a  better  drainage  system,  there  is  a 
coating  of  loess,  which  absorbs  the  excess  of  rainfall  much  more  rapidly 
than  the  till  which  forms  the  surface  of  much  of  the  Wisconsin  drift,  and 
returns  the  moisture  to  the  crops  in  seasons  of  drought  to  a  larger  extent 
than  the  till  sheet. 

The  thickness  of  di'ift  is  known  only  at  a  few  points  in  the  southwest 
part,  where  it  is  60  to  100  feet.  The  thickness  in  the  northern  and  eastern 
parts  of  the  county  apparently  averages  at  least  150  feet,  several  wells 
having  reached  that  depth  without  entering  rock.  The  drift  in  the  south- 
ern and  eastern  portions  of  the  county  is  largely  till,  but  in  the  northwestern 
part  it  apparently  consists  in  the  main  of  sand  and  gravel,  thus  resembling 
the  diift  of  Mason  County,  which  borders  it  on  the  west. 

Wells  are  usually  obtained  at  depths  of  20  or  30  feet,  which  have 
sufficient  strength  to  supply  stock  as  well  as  households.  In  a  few  cases, 
however,  wells  have  been  sunk  to  depths  of  100  or  even  200  feet. 

INDIVIDUAL   WELLS. 

The  village  of  Atlanta,  which  is  situated  on  the  outer  moraine  of  the 
Wisconsin  drift,  obtains  its  supply  for  the  waterworks  from  a  well  151  feet 
in  depth,  a  section  of  which  appears  on  p.  206.     In  the  vicinity  of  Atlanta 


708  THE  ILLINOIS  GLACIAL  LOBE. 

several  wells  reach  a  depth  of  125  feet,  and  occasionally  a  well  is  sunk  to 
a  depth  of  fully  200  feet  without  entering  rock.  The  well  di-illers  report 
that  the  upper  100  feet  is  a  softer  clay  than  the  lower  100  feet.  A  buried 
soil  is  not  uncommon  at  the  base  of  the  soft  clay.  It  is  probable  that  the 
soil  immediately  underlies  the  Wisconsin  drift,  though  it  may  in  some 
instances  be  at  a  lower  horizon. 

At  Lawndale,  situated  on  the  plain  immediately  outside  the  Wisconsin 
drift  sheet,  at  an  elevation  about  115  feet  lower  than  Atlanta,  several  wells 
have  been  sunk  to  depths  of  65  to  80  feet,  mainly  through  a  hard  till. 
Water  is  found  beneath  a  cemented  gravel  in  a  loose  gravel  or  sand.  East 
from  this  village  wells  are  in  several  instances  50  or  55  feet  in  depth,  and 
enter  gravel  below  till. 

At  Hartsburg  the  public  well  is  obtained  in  sand  below  till  at  a  depth 
of  95  feet.  Another  well  in  the  village  is  thought  to  have  struck  rock  at 
about  100  feet. 

In  the  vicinity  of  Emden,  on  the  plain  outside  the  Wisconsin  drift,  in 
the  north  part  of  the  county,  tubular  wells  are  85  to  200  feet  in  depth  with- 
out entering  rock.  They  usually  penetrate  alternations  of  till  with  sand  or 
gravel  beds.  Well  drillers  report  that  west  from  Emden  the  wells  frequently 
penetrate  a  dry  gravel  to  depths  of  90  to  115  feet.  Southwest  from  Emden 
a  sand  and  blue  silt  frequently  constitutes  almost  the  entire  section  to  a 
depth  of  at  least  100  feet.  A  well  at  Mr.  Hubbard's,  in  sec.  31,  T.  21, 
R.  4  W.,  196  feet  in  depth,  has  the  following  section: 

Section  of  the  Hubhard  well  in  Sec.  31,  T.  31,  R.  4,  W. 

Feet. 

Yellow  clay,  mainly  loess 16 

Blue  clay,  nearly  jtebbleless,  called  "blue  mud" Ij50 

Hard  blue  clay  (till?) 30 

Gravel  at  bottom. 

Total  depth 199 

At  Lincoln  a  strong  supply  of  water  is  obtained  from  sand  at  about  65 
feet  after  penetrating  beds  of  clay,  sand,  and  gravel.  The  public  water 
supply  is  mainly  obtained  by  pumping  from  neighboring-  creeks,  though 
wells  have  been  used. 

In  the  \acinity  of  Broadwell  the  drift  is  nininlv  a  blue  till  and  is  60  or 
70  feet  in  depth.  Wells  are  frequently  obtained  above  the  blue  clay  at. 
depths  of  15  or  20  feet. 


WELLS  OF  MENAKD  COUNTY,  ILLINOIS.  709 

At  Elkhart  the  drift  is  about  60  feet  in  depth,  as  follows: 
Generalized  section  of  drift  at  Elkhart,  Illinois. 

Feet. 

Loess  aud  slightly  pebbly  clay -- 12 

Black  soil  containing  wood ; 3-6 

Yellow  till .  - - 5-10 

Blue  till 30-35 

Records  of  several  wells  were  obtained  west  from  Elkhart  which  show 
a  section  similar  to  the  above  and  enter  rock  at  about  60  feet. 

At  Mount  Pulaski  the  public  water  supply  is  from  a  well  about  80  feet 
in  depth,  which  is  mainly  through  a  sandy  drift.  The  villag'e  stands  on  a 
knoll,  about  40  feet  above  the  bordering-  plain.  On  the  plain  near  Mount 
Pulaski  a  black  mucky  soil  is  penetrated  below  yellow  clay  at  a  depth  of 
16  or  18  feet,  and  wells  are  obtained  at  about  30  feet.  A  prospect  boring 
for  coal  on  the  plain  near  this  village  penetrated  92  feet  of  drift. 

MENARD   COUNTY. 
GENERAL   STATEMENT. 

Menard  County  is  situated  in  the  central  part  of  the  State,  immediately 
west  of  Logan  County  and  south  of  Mason  County.  It  has  an  area  of  only 
320  square  miles,  and  Petersburg  is  the  county  seat.  The  county  is  trav- 
ersed nearly  centrally  in  a  south-to-north  direction  by  Sangamon  River, 
and  this  stream  also  forms  a  portion  of  the  north  boundary  of  the  county. 
The  remainder  of  the  north  boundary  is  formed  by  Salt  Creek,  the  princi- 
pal tributary  of  Sangamon  River.  The  county  is  well  drained  by  these 
streams  and  their  tributaries,  and  has  also  a  coating  of  loess  which  absorbs 
the  rainfall  rapidly  and  returns  it  to  the  crops  in  seasons  of  drought. 

The  drift  has  about  the  same  constitution  as  in  southwestern  Logan 
County,  being  largely  a  hard  blue  till.  Its  depth  is  seldom  less  than  60 
feet,  and  probably  averages  at  least  100  feet.  Wells  are  usually  obtained 
at  about  35  feet,  though  a  few  have  been  sunk  to  greater  depths.  Borings 
for  coal  have  tested  the  thickness  of  the  drift  at  several  points. 

INDIVIDUAL   WELLS. 

The  public  water  supply  at  Petersburg  is  obtained  from  four  8-inch 
wells  sunk  to  depths  of  35  to  60  feet  in  the  glacial  di-ift.  A  coal  shaft  in 
the  Sangamon  Valley,  2  miles  north  of  this  city  and  at  about  65  feet  lower 
elevation,  entered  rock  at  46  feet. 


710  THE  ILLINOIS  GLACIAL  LOBE. 

In  the  vicinity  of  Greenview  the  drift  is  less  than  100  feet  in  thickness. 
The  loess  has  a  depth  of  12  to  16  feet,  and  is  separated  from  the  underlying 
till  by  a  definite  soil  horizon. 

The  record  of  a  boring-  at  Sweetwater,  published  in  the  Geology  of 
Illinois,  is  as  follows: 

Section  of  a  boring  at  Sweetwater,  Illinois, 

Feet. 

Brown  clay 40 

Sand 11 

Blue  clay 59 

Total  drift 110 

Black  soil  at  bottom  of  drift. 

Another  deep  boring  reported  in  the  Geology  of  Illinois,  is  in  a  valley 
in  sec.  2,  T.  17,  R.  6  W.,  which  reached  a  depth  of  86  feet  without  entering 
rock.     Wood  was  found  at  65  feet. 

Outcrops  of  rock  occur  in  the  west  part  of  T.  18,  R.  5  W.,  along  ra^'ines 
at  a  level  only  35  feet  below  the  neighboring  uplands,  and  wells  east  from 
there  near  the  county  line  enter  rock  at  about  70  feet.    . 

CASS  COUNTY. 
GENERAL  STATEMENT. 

Cass  County  is  situated  on  the  east  side  of  the  Illinois  River,  immedi- 
ately south  of  the  mouth  of  the  Sangamon  River,  with  Virginia  as  the 
county  seat,  and  has  an  area  of  360  square  miles.  It  is  drained  by  small 
streams  tributary  to  the  Sangamon  and  Illinois,  and  its  drainage  is  much  like 
that  of  Menard  County,  rainfall  being  disposed  of  by  the  loess  as  well  as 
by  a  well-developed  drainage  system.  There  ai-e  extensive  bottom  lands 
along  the  Sangamon  and  Illinois  rivers,  occupying  about  one-third  the  area 
of  the  countv.  These  bottoms  have  a  sandy  deposit,  though  usually  their 
soil  is  productive. 

Wells  at  Beardstown  indicate  that  the  Illinois  Valley  has  a  filling  of  at 
least  100  feet,  mainly  sand  and  gravel.  On  the  uplands  the  drift  thickness 
is  known  to  the  writer  at  only  two  points — Ashland  and  Virginia — being 
85  feet  at  the  former  and  187  at  the  latter  vfllage. 

Wells  are  usually  obtained  at  25  to  50  feet,  both  on  the  bottom  lands 
and  on  tlie  upland.  The  shallower  ones  obtain  their  supply  above  tlie  lilue 
till,  but  tlie  deeper  ones  on  the  uplands  enter  that  deposit  n  few  feet. 


WELLS  OF  SCHTTYLEE  COUNTY,  ILLINOIS.  711 


INDIVIDUAL   WELLS. 


The  public  water  supply  at  Beardstown  is  obtained  from  driven  wells 
about  80  feet  in  depth.  The  wells  show  a  gradation  downward  from  sand 
through  fine  gravel  to  coarse  gravel.  Several  artesian  wells  have  been  sunk 
at  this  city  which  penetrate  about  100  feet  of  drift  and  reach  depths  of  1,050 
to  1,100  feet.  A  flow  of  water  is  obtained  f'om  strata  supposed  to  be 
Devonian  at  about  350  feet,  and  another  flow  with  small  amounts  of  gas 
and  oil  at  500  to  600  feet,  and  a  third  flow  from  near  the  bottom.  The 
wells  are  estimated  to  have  a  capacity  of  about  175  gallons  a  minute. 

At  Virginia  wells  are  usually  obtained  at  25  to  50  feet  from  sand  and 
gravel  below  clay.  The  beds  of  sand  and  gravel  are  not  certain  to  occur, 
and  only  those  wells  which  are  so  fortunate  as  to  strike  them  obtain  an 
abundant  supply  of  water.  Dr.  J.  F.  Snyder,  of  Virginia,  reports  that 
during  the  drought  of  1894  and  1895  about  70  per  cent  of  the  wells  in  the 
vicinity  of  Virginia  became  dry.  The  coal  shaft  at  this  village,  220  feet  in 
depth,  penetrated  187  feet  of  drift.  It  was  mainly  through  till,  but  a  black 
soil  was  passed  through  at  67  to  70  feet.  This  coal  shaft  is  stated  by  Dr. 
Snyder  to  have  afforded,  during  the  drought  referred  to  above,  about  375 
baiTels  of  water  a  day.  A  boring  at  Virginia  730  feet  in  depth  obtained  a 
water  sti'ongly  impregnated  with  sulphur  and  iron,  which  is  considered  unfit 
for  general  use.  A  remarkable  thickness  of  peat  was  penetrated  by  a  well  at 
Mr.  Oldi'idge's,  in  this  village,  of  which  an  account  appears  on  a  previous 
page  (p.  127).     The  section  at  Ashland  has  also  been  discussed  (p.  127). 


SCHUYLER  COUNTY. 
GENERAL    STATEMENT. 


Schuyler  County  is  situated  on  the  west  border  of  the  Illinois  River, 
northwest  from  Cass  County,  and  has  an  area  of  430  square  miles,  with 
Rushville  as  the  county  seat.  Crooked  Creek  crosses  its  northwest  corner 
and  forms  a  portion  of  the  western  border.  No  other  prominent  sti-eam 
occurs  in  the  county,  but  it  has  a  somewhat  mature  drainage  system,  and 
portions  of  the  county  are  very  much  broken  by  ravines.  There  is  a  loess 
coating,  as  in  the  counties  east  of  the  Illinois  River,  which  adds  to  the  ready 
disposition  of  the  rainfall.     The  Illinois  bottoms  lay  mainly  east  of  the 


712  THE  ILLINOIS  GLACIAL  LOBE. 

river  opposite  this   county,  but  extend  about  2  miles  into  the  county  near 
the  south  border,  above  the  mouth  of  Crooked  Creek. 

The  di-ift  deposits  appear  to  be  much  thinner  than  in  the  counties 
east  of  the  Ilhnois,  just  discussed,  rock  being  entered  in  many  places  at 
a  de2:)th  of  about  30  feet.  The  wells  are  usually  obtained  above  the  rock 
at  depths  of  15  or  20  feet. 

INDIVIDUAL  WELLS. 

At  Rushville  the  present  public  supply  is  from  impounded  water  fed 
by  springs.  From  1894  to  1896  a  well  2,500  feet  in  depth  supplied  the 
waterworks.  The  quality  of  the  water  was  found  so  unpleasant  that  its 
use  was  discontinued.  The  distance  to  rock  varies  50  feet  or  more  within 
the  limits  of  this  town.  At  the  creamery  rock  was  entered  at  only  20 
feet,  but  at  the  northeast  corner  of  the  public  square  a  well  reached  a 
depth  of  70  feet  without  entering  rock.  A  coal  mine  on  the  outskirts  of 
the  town  enters  rock  at  about  40  feet.  The  drift  is  mainly  sand  and  gravel, 
while  in  the  well  at  the  public  square  it  is  mainly  till. 

East  from  Rushville,  in  the  vicinity  of  Pleasant  View,  wells  are  reported 
to  enter  a  blue  shale  at  de]3ths  of  17  to  24  feet,  but  as  some  of  them  are 
also  thought  to  enter  gravel  below  this  material  it  is  probable  that  the 
material  is  till  rather  than  shale.  These  wells  enter  limestone  at  about  60 
feet,  and  this  probably  represents  the  thickness  of  the  drift. 

In  the  interior  of  the  county,  northwest  from  Rushville,  wells  are  found 
to  enter  rock  at  depths  of  30  to  50  feet,  though  occasionally  a  greater  depth 
is  reached  without  encountering  rock. 

BROWN  COUNTY. 

GENERAL  STATEMENT. 

Brown  County  is  situated  on  the  west  border  of  the  Illinois  River, 
immediately  south  of  Schuyler,  and  has  an  area  of  300  square  miles,  with 
Mount  Sterling  as  the  county  seat.  Crooked  Creek  forms  a  portion  of  the 
northern  border  and  receives  the  drainage  of  the  northeast  half  of  the 
county.  McKee's  Creek  crosses  the  southern  border  of  the  county  and 
drains  its  southwestern  portion.  In  thickness  and  structm'e  the  drift  in  this 
county  is  similar  to  that  of  Schuyler.  The  surface  also  is  generally  much 
eroded  and  the  drift  is  capped  by  a  deposit  of  loess.     The  thickness  of  the 


WELLS  OF  ADAMS  COUNTY,  ILLINOIS.  713 

loess  is  usually  but  10  or  15  feet.  On  the  borders  of  the  Illmois,  however, 
it  attains  iu  one  place  a  thickness  of  over  100  feet,  a  large  part  of  the  bluff 
being  formed  of  that  deposit.  The  Illinois  bottoms  occupy  an  average 
width  of  about  two  miles  along  the  east  border  of  the  county,  and  the 
higher  portions  of  the  bottoms  are  sandy  and  gravelly,  but  the  lower  por- 
tions are  covered  with  a  deposit  of  muck. 

Although  the  drift  is  comparatively  thin  throughout  much  of  the 
county,  wells  are  usually  obtained  without  entering  the  rock.  The  rock 
consists  largely  of  a  sandy  shale,  which  often  affords  water  in  fair  amount. 

INDIVIDUAL   WELLS. 

At  Mount  Sterling  the  wells  are  usually  obtained  from  sandy  clay  at 
depths  of  16  to  25  feet.  The  Manual  of  American  Waterworks  states  that 
the  public  supply  is  from  an  open  well. 

In  the  vicinity  of  Mount  Sterling  shale  is  often  struck  at  about  25 
feet.  The  Illinoian  drift  embraces  only  about  half  this  depth,  there  being 
10  or  12  feet  of  loess  at  the  surface. 

In  the  vicinity  of  Versailles  wells  are  often  sunk  to  a  depth  of  50  feet, 
and  they  are  largely  through  loess. 

At  Mound  Station,  in  the  northwest  part  of  the  county,  a  well  at  the 
lumber  yard  enters  rock  at  44  feet.  The  mounds  or  low  hills  immediately 
northwest  of  this  station,  which  give  it  its  name,  are  said  to  have  a  nucleus 
of  rock  which  causes  their  relief  of  50  feet  or  more  above  the  plain. 

ADAMS  COUNTY. 
GENERAL  STATEMENT. 

Adams  County  borders  the  Mississippi  River  in  the  western  part  of  the 
State,  with  Quincy  as  the  county  seat,  and  has  an  area  of  830  square  miles. 
The  northern  tliird  of  the  county  is  drained  westward  tlu'ough  Bear  Creek, 
the  southwestern  part  is  drained  westward  through  Mill  Creek,  and  the 
southeastern  part  is  drained  eastward  through  McKee's  Creek,  a  tributary 
of  the  Illinois  River.  In  the  western,  central,  and  southern  portions  of  the 
county  there  are  several  ridges  of  drift  formed  near  the  western  border  of 
the  Illinoian  drift  sheet  and  trending  in  a  general  northwest-southeast  direc- 
tion.    These  ridges  are  each  a  mile  or  less  in  averag-e  width  and  rise  20 


o 


to  60  feet  above  the  bordering  plains.     Their  distribution  is  shown  on  the 


714  THE  ILLINOIS  GLAUIAL  LOBE. 

glacial  map,  PI.  VI.  Aside  from  these  few  ridges,  the  drift  has  a  plane 
surface  and  the  drift  filling  is  sufficient  to  nearly  conceal  preglacial  valleys. 
With  the  exception  of  a  narrow  strip  along  the  Illinois-Mississippi  divide, 
in  the  central  and  northeastern  parts  of  the  county,  the  surface  is  generally 
much  eroded.  In  the  vicinity  of  the  Mississippi  bluffs  there  is  a  thick 
deposit  of  loess,  in  places  reaching  50  or  60  feet,  but  within  5  or  6  miles 
back  from  the  brow  of  the  bluffs  the  thickness  decreases  to  10  feet  or  less. 
The  loess  affords  quick  absorption  for  the  rainfall  and  supplies  moisture  to 
the  crops  in  seasons  of  drought. 

The  glacial  drift  is  largely  till.  It  is  underlain  in  places  by  deposits 
of  preglacial  sand,  first  brought  to  notice  by  Worthen  and  later  examined  in 
more  detail  by  Salisbury  and  the  writer.  The  heaviest  deposits  noted  are 
in  the  vicinity  of  Mendon,  in  the  northwest  part  of  the  county,  but  deposits 
of  considerable  depth  also  occur  along  the  Illinois-Mississippi  divide  in  the 
southeast  part  of  the  county.  In  the  former  situation  their  elevation  is 
150  to  200  feet  above  the  Mississippi  River,  and  in  the  latter  nearly  300 
feet  above  that  stream,  or  on  about  the  highest  rock  surface  known  within 
the  limits  of  the  county.  The  thickness  of  the  deposits  and  their  relation 
to  wells  is  set  forth  in  the  discussion  below. 

The  wells  of  this  county  are  usually  obtained  at  moderate  depths  in  the 
drift.  In  nearly  every  township,  however,  several  deep  wells  have  been 
sunk.  Records  of  59  such  wells  were  collected  which  show  an  average 
depth  of  about  63  feet.  The  rock  was  struck  in  36  wells  at  an  a%-erage 
depth  of  61  feet.  In  the  remaining  23  wells  the  average  depth  is  65  feet. 
From  these  wells  it  appears  probable  that  the  average  thickness  for  the 
county  is  not  less  than  65  feet.  None  of  the  well  records  were  obtained  in 
the  Mississippi  bottoms,  which  occupy  about  100  square  miles  of  the  county 
and  in  which  the  drift  is  probably  more  than  100  feet  in  average  depth,  for 
the  valley  floor  of  the  preglacial  river  was  cut  to  a  level  fully  100  feet 
below  the  present  stream. 

INDIVIDUAL   WELLS. 

The  pulilic  water  supply  for  the  city  of  Quincy  is  pumped  from  the 
Mississi])pi  River,  but  there  are  numerous  private  wells  in  the  city,  ranging 
in  depth  from  90  to  200  feet.  These  wells  are  mainly  through  limestone. 
In  parts  of  the  city  30  feet  or  more  of  loess  is  peueti'ated  before  the  lime- 
stone is  entered. 


WELLS  OF  ADAMS  GOUNTY,  ILLINOIS.  715 

At  Mendon  the  public  water  supply  is  from  a  well  1,010  feet  in 
depth,  fi'om  which  water  is  pumped  to  a  tank.  This  well  passed  through 
about  20  feet  of  loess  and  glacial  drift,  beneath  which  a  deposit  of  orange- 
colored  sand,  presumably  preglacial,  was  found,  which  extends  to  the  lime- 
stone at  70  feet  from  the  surface.  Another  well,  at  the  public  square,  on 
ground  20  feet  higher  than  the  deep  well,  also  penetrated  a  large  amount 
of  sand  and  entered  limestone  at  a  depth  of  94  feet.  Samples  of  this  sand 
examined  with  acid  are  apparently  free  from  calcareous  material,  thus 
differing  markedly  from  the  glacial  sands  of  this  region,  which  are  com- 
posed largely  of  limestone  fragments.  The  sand  is  also  stained  a  deeper 
yellow  than  that  associated  with  glacial  drift. 

A  well  at  W.  W.  Benton's,  1  mile  west  of  Mendon,  reached  a  depth  of 
400  feet,  but  the  water  supply  is  mainly  from  about  200  feet.  The  drift 
penetrated  in  this  well  is  as  follows,  the  determinations  being  made  by  the 
writer  at  the  time  the  well  was  sunk: 

Section  of  Benton  well  near  Mendon,  Illinois. 

Feet. 

Loess 12 

Gray  gummy  soil 2 

Yellow  sand 18 

Gray  gummy  clay,  apparently  a  soil 6 

Gray  sandy  clay  with  few  pebbles 35 

Blue  clay  with,  a  few  pebbles ; 10 

Total 85 

On  ravines  southeast  of  Mendon  the  following  strata  are  exposed: 
.  Section  in  a  ravine  southeast  of  Mendon. 

Peet. 
Loess 8 

Black  gummy  soil-like  clay _ 1_2 

Sand .5_10 

Gray  sandy  clay,  resembling  soil 1_2 

Brownish  clay  or  clayey  sand  with  pebbles,  of  variable  depth,  and  underlain  by  yellow  sand, 
apparently  preglacial 20-40 

In  the  vicinity  of  Fowler,  wells  are  usually  obtained  in  the  di-ift  at 
depths  of  20  to  40  feet,  but  a  well  at  the  mill  was  sunk  to  a  depth  of  262 
feet  and  entered  rock  at  80  feet. 

At  Coatsburg,  a  well  at  the  mill  reached  a  depth  of  95  feet  without 
entering  rock.  The  drift  is  mainly  till  to  a  depth  of  65  feet,  beneath  which 
there  is  a  blue  clay  with  sandy  partings  which  is  thought  from  the  descrip- 
tion to  be  a  water  deposit.     Waterworks  recently  constructed  at  this  village 


716  THE  ILLINOIS  GLACIAL  LOBE. 

use  a  well  for  supply,  but  the  depth  is  not  ascertained.  A  coal  shaft  1  mile 
east  of  Coatsburg,  reported  in  the  Geology  of  Illinois,  passed  through  a  clay 
similar  to  that  at  the  mill  in  its  lower  portion,  whicli  was  separated  from  the 
overlying-  till  bv  a  black  soil,  the  following  being  the  section,  supplemented 
by  notes  taken  bv  the  writer  from  the  residents  and  from  exposures  near 
the  coal  shaft;  it  should  be  compared  with  the  section  given  on  page  62. 

Section  in  a  boring  for  coal  a  mile  east  of  Coatsburg,  Illinois. 

Feet. 

Soil  and  yellow  clay 6 

Gray  or  ashy  clay,  resembling  a  soil *i 

Yellow  till,  becoming  gray  or  blue  near  bottom 10-15 

Bill  -gray  till 70-75 

Black  soil -- Si 

Strati  tied  clay 6 

Tough  blue  clay 20 

Total  drift 118 

At  the  Countv  Infirmary  near  Coatsburg,  a  well  entered  rock  at  a 
depth  of  165  feet.  The  upper  6.5  feet  appears  to  be  largely  till,  below 
which  is  a  blue  silt  with  sand  partings,  perhaps  a  water  deposit.  A  boring 
at  ]Mr.  Henry's,  near  the  infirmary,  peneti-ated  a  similar  section  and  entered 
rock  at  160  feet.  Another  well  on  the  infirmary  farm  is  only  58  feet  in 
depth.  After  penetrating  about  40  feet  of  till  it  entered  sand  and  gravel, 
which  furnished  the  water. 

At  Camp  Point  wells  are  usually  obtained  at  25  to  30  feet.  A  few 
have,  however,  been  sunk  to  a  depth  of  45  or  50  feet,  at  which  depth  the 
first  rock  is  struck. 

At  Clayton  rock  is  usually  entered  at  a  depth  of  30  or  40  feet.  The 
depth  of  wells  supplying  the  waterworks  has  not  been  ascertained;  the  sys- 
tem was  but  recently  introduced. 

At  Liberty  several  deep  wells  have  been  sunk  which  show  a  range  in 
thickness  of  drift  from  47  feet  to  at  least  90  feet.  A  well  at  Collins's  mill, 
90  feet  in  depth,  has  the  following  section: 

Section  of  a  well  at  Collins's  mill  in  Liherty,  Illinois. 

Feet, 

Till,  mainly  of  yellow  color 50 

Blue  clay  containing  much  wood,  but  with  few  pebbles 33 

Sand  with  water 5 

To ta  1  depth 90 

A  well  in  Liberty,  at  William  Lytle's,  after  penetrating  52  feet  of  till, 
entered  a  sandv  blue  dav  (•(int;iining  wood.     AVater  was  found  in  thi.s  clay. 


WELLS  OF  ADAMS  COUNTY,  ILLINOIS.  717 

A  well  at  Mr.  Grubb's,  on  ground  20  feet  hig-her,  entered  Coal  Measures 
shale  at  47  feet.  The  drift  is  largely  g-ravel.  Mr.  Grubb,  who  has  had 
some  experience  as  a  well  driller,  reports  that  over  an  area  of  several 
square  miles  northwest  from  Libert}^  the  till  has  a  thickness  of  about  .50 
feet  and  is  underlain  bj  a  dark-blue  clay  similar  to  that  of  wells  at  Liberty 
and  probably  similar  to  that  at  the  infirmary  noted  above.  In  a  well  exam- 
med  by  the  writer  while  in  process  of  excavation,  a  section  of  which  appears 
on  page  61,  it  was  found  that  the  dark-blue  clay  is  a  calcareous  silt  free  from 
pebbles. 

In  the  vicinity  of  Burton  wells  are  usually  obtained  at  about  30  feet, 
near  the  base  of  the  drift.  Two  wells  southwest  of  the  village  reach  a 
much  greater  depth  and  apparently  strike  into  a  preglacial  valley.  One  at 
Mr.  Dietreck's,  on  the  east  bluff  of  Mill  Creek,  has  a  depth  of  200  feet  and 
enters  rock  at  160  feet.  A  well  at  Mrs.  Ihrig's,  on  the  west  bluff  of  Mill 
Creek,  reached  a  depth  of  155  feet  without  entering  rock.  It  was  mainlv 
through  yellow  clay  to  a  depth  of  105  feet,  beneath  which  the  clay  is  of 
blue  color.     Sand  was  struck  near  the  bottom. 

In  the  vicinity  of  Newtown  (Adams  post-office)  wells  not  infrequently 
reach  a  depth  of  75  feet,  there  being  a  ridge  of  drift  leading  past  the  village 
in  a  northwest-southeast  course,  in  which  wells  are  sunk  to  a  greater  depth 
than  on  the  bordering  plains.  The  village  well,  75  feet  in  depth,  is  reported 
to  be  mainly  till  with  gravel  at  bottom.  Another  well  on  the  ridge  south- 
east of  the  Aallage,  at  the  residence  of  Mrs.  Wittemeyer,  the  section  of 
which  is  given  on  page  59,  passed  through  a  gray  muck  or  soil  below  till  at 
40  to  45  feet,  which  is  about  the  level  of  the  base  of  the  ridge.  Beneatli 
this  soil  was  a  sandy  till  grading  into  sand  below,  and  water  is  obtained 
in  this  sand  at  80  to  82  feet. 

At  the  village  of  Payson,  which  is  located  on  a  ridge  of  drift,  rock  is 
entered  at  a  depth  of  about  90  feet,  and  the  drift  is  largely  of  sandy  consti- 
tution. A  well  at  Mr.  Barnard's,  1  mile  west  of  this  village,  after  penetrat- 
ing alternations  of  clay  and  gravel  to  a  depth  of  60  feet,  passed  into  a 
reddish  clay,  apparently  formed  by  the  decomposition  of  limestone,  which 
was  17  feet  in  thickness  and  extended  to  the  rock. 

At  Plainville  the  village  well  penetrates  about  20  feet  of  clay  contain- 
ing few  pebbles,  beneath  which  is  ordinary  till  extending  to  the  rock,  which 
is  entered  at  about  40  feet.     The  drift  in  that  vicinity  seldom  exceeds  40 


718  THE  ILLINOIS  GLACIAL  LOBE. 

feet  in  depth,  and  wells  are  often  sunk  some  distance  into  the  underlying 
limestone. 

At  Beverly  the  village  well  is  73  feet  in  dejjth,  and  apparently  enters 
a  preglacial  sand  in  the  lower  20  feet.  This  interpretation  is  made,  how- 
ever, from  the  examination  of  a  well  in  process  of  excavation  about  one- 
half  mile  east  of  the  village,  at  the  residence  of  J.  Sykes,  the  section  of 
■vfhich  appears  on  page.  60.  Mr.  Sykes's  well  penetrated  an  orange-colored 
quartz  sand  in  its  lower  15  feet,  which  is  entirely  free  from  calcareous 
material  and  is  apparently  much  older  than  the  glacial  drift.  It  so  happens 
that  at  this  well  there  occurs  at  the  base  of  the  glacial  drift  a  bed  of  gravel 
and  sand  which  is  highly  calcareous,  and  is  much  fresher  in  appearance 
than  the  quartz  sand  just  referred  to,  a  feature  which  lends  much  support 
to  the  intei'pretation  of  the  preglacial  age  of  the  orange-colored  sand. 

Along  the  Illinois-Mississippi  divide  northwest  from  Beverly  wells 
occasionally  reach  a  depth  of  90  feet  without  entering  solid  rock.  They 
are  reported  to  pass  through  an  orange-colored  sand  in  the  lower  part,  which 
is  probably  similar  to  that  examined  in  the  well  at  Mr.  Sykes's.  Probably 
further  study  in  the  region  would  result  in  the  discovery  of  natural  expo- 
sures, for  the  ravines  leading  eastward  from  this  divide  are  frequently  cut 
to  sufficient  depth  to  reach  the  level  of  the  orange-colored  sand. 

PIKE  COUNTY. 
GENERAL  STATEMENT. 

Pike  County  is  situated  between  the  Mississippi  and  Illinois  rivers, 
immediately  south  of  Adams  and  Brown  counties,  and  has  an  area  of  795 
square  miles,  with  Pittsfield  as  its  county  seat.  Fully  three-foui"ths  of  the 
county  is  tributary  to  the  Mississippi  River.  It  is  probable  that  a  larger 
portion  is  now  tributary  to  the  Mississippi  than  in  preglacial  times.  As 
noted  on  page  480,  the  headwater  portion  of  Bay  Creek  leads  southeast- 
ward, as  if  to  join  the  Illinois,  but  a  morainic  ridge  on  its  east  border 
prevents  its  entering  the  Illinois,  and  it  passes  westward  through  a  hilly 
region  which  probably  once  constituted  the  divide  between  the  Mississippi 
and  the  Illinois,  and  thus  becomes  tributaiy  to  the  Mississippi. 

The  interior  portion  of  the  county  is  traversed  by  a  series  of  drift 
ridges,  which  are  the  continuation  of  those  noted  in  Adams  County,  and 
wliicli,    like  those   of  Adams   Count\-,    liave   a  noi-thwe.st-southeast  trend. 


WELLS  OF  PIKE  COUNTY,  ILLmOlS.  719 

Two  of  the  ridg-es  extend  but  little  south  of  Pittsfield,  but  a  third  ridge, 
which,  as  noted  above,  follows  the  east  border  of  Bay  Creek,  continues 
southeastward  to  the  Illinois  bluff,  which  it  strikes  between  Montezuma  and 
Bedford.  These  ridges  constitute  the  highest  land  within  the  county,  and 
reach  in  places  an  elevation  of  nearly  900  feet,  and  throughout  much  of 
their  course  are  about  800  feet  above  tide.  The  rivers  bordering-  the 
county  have  an  elevation  of  less  than  450  feet  above  tide,  or  about  400  feet 
below  the  general  level  of  these  ridges.  Much  of  the  upland  in  the  county 
stands  nearly  300  feet  above  the  bordering  streams. 

Aside  from  the  drift  ridges  justx  mentioned,  the  drift  of  the  county  is  a 
thin  deposit,  scarcely  forming  a  continuous  coating.  But  in  the  drift  ridges 
a  thickness  of  about  100  feet  is  in  places  attained,  and  the  tliickness  is 
seldom  less  than  50  feet.  The  di-ift  in  these  ridges  consists  largely  of  a 
clay  in  which  pebbles  are  less  thoroughly  intermixed  than  in  typical  till. 
The  dumps  of  some  wells  examined,  which  reached  the  depth  of  60  feet, 
show  scarcely  a  handful  of  pebbles  on  their  surface,  while  neighboring  wells 
or  natural  exposures  may  contain  a  large  amount  of  stony  material.  This 
imperfect  intermingling  of  the  stony  and  clayey  material  is  probably  due 
to  the  derivation  of  much  of  the  drift  from  the  immediate  vicinity  and  the 
consequent  short  distance  that  it  was  transported.  The  loess  forms  a  heavy 
deposit  on  the  borders  of  the  Illinois  and  Mississippi  rivers,  its  usual  thick- 
ness being  25  or  30  feet,  but  in  the  interior  of  the  county  its  thickness 
decreases  to  scarcely  10  feet.  On  the  higher  portions  of  the  drift  ridges 
it  is  in  places  only  4  or  5  feet  in  depth. 

Along  the  drift  ridges  wells  are  often  obtained  without  entering  the 
rock,  but  elsewhere  on  the  uplands  strong  wells  are  seldom  obtained  in 
the  drift.  In  the  valleys  of  the  Mississippi  and  Illinois  wells  are  usually 
obtained  in  sand  and  gravel  at  about  the  level  of  these  streams. 

INDITIDTJAL   WELLS. 

In  the  vicinity  of  Barry,  in  the  northwest  part  of  the  county,  the  wells 
are  usually  obtained  in  rock  at  a  depth  of  60  to  85  feet.  The  loess  and 
di'ift  is  16  to  35  feet  in  depth.  The  public  water  supply  is  from  a  well 
2,510  feet  in  depth,  which  has  a  head  135  feet  below  the  surface,  except 
when  filled  with  surface  water  after  an  intermission  from  pumping.  The 
water,  unless  diluted  with  surface  water,  is  too  salt  for  domestic  use  and  the 
majority  of  the  citizens  depend  upon  private  wells. 


720  THE  ILLINOIS  GLACIAL  LOBE. 

At  the  A-illag-e  of  Baylis,  situated  on  the  crest  of  the  highest  drift  ridge 
in  the  county,  a  village  well  was  sunk  to  a  depth  of  90  feet  without  enter- 
ing rock.  The  upper  30  feet  is  of  a  clayey  constitution,  the  remainder  a 
fine  sand.  Wells  are  obtained  in  this  village  at  the  top  of  this  sand.  In 
ra%'ines  1  to  2  miles  southeast  of  Baylis  there  are  exposures  of  drift  about 
50  feet  in  depth  showing  a  brown  surface  clay  with  few  pebbles,  extending 
to  a  depth  of  30  or  40  feet,  beneath  which  there  is  a  pebbh'  brown  clay, 
streaked  with  gray,  exposed  to  a  depth  of  10  or  20  feet.  On  the  west  slope 
of  the  di-ift  ridge,  west  and  southwest  from  Baylis,  the  pebbly  clay  near  the 
base  of  the  ridge  is  more  gravelly  than  on  the  eastern  slope,  perhaps  because 
of  the  removal  of  the  clayey  material  as  an  outwash  from  the  ice  sheet. 
The  section  of  a  well  at  the  residence  of  A.  Hill,  2  miles  north  of  Baylis, 
appears  on  page  63. 

Along  the  county  line  northwest  from  Baylis  the  following  section  of 
drift  deposits  was  found: 

Section  at  roadside  on  county  line  northicest  of  Baylis,  Illinois. 

Feet. 

Loess  or  yellow  silt 5 

Ashy  clay,  probably  soil 1-3 

Yellowish-gray  clay  with  few  pebbles 40-50 

Sand,  gray  or  yellow,  in  thin  beds 1-  2 

Ash-colored  clayey  sand,  resembling  soil---. 2-  5 

Cobble  and  gravel,  with  Canadian  rocks 5-15 

Total  drift r 60-85 

At  New  Salem  a  well  near  the  railway  station  obtains  water  in  a 
gi-avelly  clay  at  a  depth  of  30  feet,  but  in  the  main  part  of  the  village  wells 
usually  enter  rock  at  about  20  feet  and  obtam  tvater  at  depths  of  40  to  50 
feet. 

In  the  vicinity  of  Griggsville  the  loess  has  a  thickness  of  about  15  feet. 
Beneath  it  is  a  brown  clay  in  which  there  are  but  few  pebbles  and  which 
apparently  extends  to  the  rock.  The  village  of  Grig-gsAalle  stands  upon  a 
slight  elevation  in  which  rock  is  nearly  at  the  surface,  but  on  the  bordering 
plain  rock  is  entered  at  greater  depth,  25  to  35  feet. 

In  tlie  vicinity  of  Detroit  and  i\Iilton  rock  is  occasionally  entered  at 
30  feet,  but  wells  along  the  drift  ridge  west  and  south  from  these  villages 
are  sunk  to  depths  of  50  or  75  feet  without  entering  the  rock.  A  well  at 
Marion  Petty's,  south  of  Milton,  is  reported  to  have  passed  through  a  black 
earth  or  soil  containing  wood  at  the  base  of  the  glacial  drift,  30  to  35  feet 
from  the  surface. 


WELLS  OF  SOOTT  COUNTY,  ILLINOIS.  721 

At  Time  the  village  well  has  a  depth  of  70  feet.  For  a  distance  of  50 
feet  it  is  tlirough  a  clay  of  brown  color  carrying  few  pebbles.  The  I'emain- 
der  is  through  a  blue  clay  of  the  consistency  of  putty.  Eavines  in  that 
vicinity  show  about  20  feet  of  loess,  beneath  which  is  a  slightly  pebbly 
brown  clay.  A  well  at  J.  E.  Dinsmore's,  2  miles  south  of  Time,  reached  a 
depth  of  60  feet,  mainly  through  pebbly  clay,  and  did  not  strike  rock.  Mr. 
Dinsmore  made  another  well  in  a  ravine  at  an  elevation  about  40  feet 
below  the  one  at  his  residence  which  passed  tlu-ough  a  black  muck  below 
brown  clay  at  a  depth  of  40  to  45  feet  and  entered  a  red  clay  similar  to  the 
residuary  clay  formed  from  limestone  in  that  vicinity  It  had  not  struck 
solid  rock  at  a  depth  of  50  feet. 

At  Pittsfield  the  public  water  supply  is  from  a  well  2,200  feet  in  depth, 
which  is  used  for  fire  protection  and  street  sprinkling  only.  Private  wells 
are  obtained  at  moderate  depth  in  the  rock,  seldom  more  than  50  feet.  On 
the  drift  ridges  west  from  Pittsfield  wells  reach  depths  of  30  to  50  feet 
without  entering  rock,  obtaining-  their  water  from  sandy  drift  associated 
with  the  clay. 

At  Nebo,  in  the  valley  of  Bay  Creek,  wells  are  obtained  at  only  15  or 
20  feet  in  sandy  beds  at  about  the  level  of  the  creek.  On  the  bordering 
uplands  wells  are  sunk  into  rock  to  depths  of  50  or  even  100  feet. 

SCOTT  COUNTY. 
GENERAL    STATEMENT. 

Scott  County  has  its  west  border  on  the  Illinois  River,  opposite  Pike 
County.  Its  area  is  but  250  square  miles,  and  Winchester  is  the  county 
seat.  It  is  drained  westward  by  tributaries  of  the  Illinois,  of  which  the 
principal  ones  are  Mauvaise  Terre  and  Big  Sandy  creeks.  The  Illinois 
bottoms  occupy  a  strip  about  3  miles  in  average  width  along  the  west 
border  of  the  county.  The  uplands  have  a  coating  of  loess,  which  is  25  to 
50  feet  in  thickness  on  the  border  of  the  Illinois,  but  decreases  eastward  to 
scarcely  more  than  10  feet  at  the  east  line  of  the  county.  The  drainage 
lines,  together  with  the  loess,  dispose  of  the  rainfall  rapidly.  In  the  Illinois 
River  bottoms  the  sand  is  in  places  so  light  as  to  be  barren  in  seasons  of 
drought. 

The  drift  in  portions  of  the  county  is  very  thick,  there  being  along  the 
Illinois  bluffs  wide  stretches  in  which  no  rock  is  exposed,  though  the  bluffs 

MON  XXSVIII 46 


722  IHE  ILLINOIS  GLACIAL  LOBE. 

are  over  100  feet  in  lieig-ht.  But  in  portions  of  the  county  the  drift  is  only 
20  or  30  feet  in  deptli.  The  drift  filHng  is  sufficient  to  greatly  conceal  the 
courses  of  preglacial  tributaries  of  the  Illinois.  Till  fonns  the  principal 
part  of  the  drift,  though  in  some  parts  of  the  Qounty  wells  pass  through  a 
large  amount  of  gravel  and  sand.  The  wells  are  usually  20  to  40  feet  in 
deptli  and  obtain  water  from  the  drift,  very  seldom  entering  the  rock. 

INDIVIDUAL    WELLS. 

In  the  vicinity  of  Winchester  wells  are  usually  obtained  at  a  depth  of 
20  or  30  feet,  but  a  well  at  the  grist  mill  was  sunk  to  a  depth  of  412  feet. 
It  has  a  head  60  feet  below  the  surface,  or  470  feet  above  tide. 

In  the  vicinity  of  Manchester  wells  are  obtained  at  a  depth  of  20  or  30 
feet.     A  coal  shaft  enters  rock  at  about  60  feet. 

In  the  vicinity  of  Alsey  wells  are  obtained  at  about  40  feet.  They 
penetrate  8  or  10  feet  of  loess,  and  then  pass  through  till  to  the  water- 
bearing bed  at  bottom. 

Near  Glasgow,  on  the  Illinois  River  bluff,  wells  usually  pass  through 
about  25  feet  of  loess,  20  feet  of  yellow  till,  and  30  feet  or  more  of  blue 
till  before  entering  rock.     In  some  cases  they  are  obtained  above  the  rock. 

MORGAN    COUNTY. 
GENERAL   STATEMENT. 

Morgan  County  is  situated  north  and  east  of  Scott  County  and  touches 
the  Illinois  River  for  a  few  miles  on  its  northwest  border.  It  has  an  area  of 
680  square  miles,  and  Jacksonville  is  the  county  seat.  It  is  drained  west- 
ward to  the  Illinois  River  through  several  creeks,  of  which  Indian  and 
Mauvaise  Terre  creeks  are  the  largest.  Like  Scott  County,  this  county  has 
a  heavy  coating  of  loess  on  the  border  of  the  Illinois  River,  but  only  a  thin 
deposit  a  few  miles  back  from  the  Illinois  The  loess  and  drainage  lines,  as 
in  Scott  County,  give  excellent  drainage. 

The  drift  is  tliiii  in  the  southeast  portion  of  the  county,  rock  being  at 
depths  of  but  20  or  30  feet  in  many  of  the  wells,  but  in  the  remainder  of 
the  county  the  thickness  generally  exceeds  50  feet  and  in  places  reaches 
at  least  150  feet.  It  consists  largely  of  till,  but-  gravel  and  sand  beds  are 
sufficiently  abundant  to  supply  water  for  most  of  tlie  wells.  The  wells  are 
sehhun  sunk  to  de})ths  of  more  than  40  or  60  feet. 


WELLS  OF  MORGAN  COUNTY,  ILLINOIS.  723 


INDIVIDUAL   WELLS. 


In  the  extreme  northwest  part  of  the  county,  on  the  llHnois  bottoms, 
wells  are  obtained  in  sand  at  30  to  50  feet,  or  at  about  the  level  of  the 
Illinois  River.  On  the  bluffs  they  are  sunk  through  20  feet  or  more  of  loess 
before  entering  glacial  drift.  Rock  is  occasionally  struck  in  that  part  of  the 
county  at  about  40  feet,  but  wells  usually  obtain  water  above  the  rock. 

At  Chapin  the  shafts  or  borings  for  coal  pass  through  about  12  feet  of 
loess,  beneath  which  is  a  sheet  of  till  extending-  to  the  rock,  which  is  entered 
at  40  to  50  feet.  Wells  in  several  instances  have  been  sunk  entirely 
throug-h  the  drift,  but  they  usually  obtain  water  at  about  20  feet. 

At  Jacksonville  wells  are  usually  obtained  at  20  to  40  feet,  but  the 
public  water  supply  is  from  two  deep  artesian  wells,  one  of  which  is  2,373 
and  the  other  3,028  feet  in  depth.  The  wells  are  situated  on  low  ground, 
about  30  feet  below  the  level  of  the  Chicago  and  Alton  depot,  and  water 
will  rise  a  few  feet  above  the  surface.  In  the  shallower  well  it  is  stated  to 
rise  15  feet  and  in  the  deeper  one  30  feet  above  the  well  mouth.  Attention 
is  here  called  to  an  error  which  appears  in  the  present  author's  paper  in  the 
Seventeenth  Annual  Report,  the  head  at  the  deep  well  being  given  as  30 
feet  below  the  surface,  instead  of  30  feet  above.  The  drift  at  the  artesian 
wells  is  about  140  feet  in  thickness  and  consists  mainly  of  till.  A  boring 
for  coal  east  of  the  city  penetrated  154  feet  of  di-ift,  mainly  till,  except 
about  10  feet  of  sand  at  the  bottom. 

There  is  a  series  of  drift  knolls  leading  from  Jacksonville  southwest- 
ward  3  or  4  miles  on  which  several  wells  have  been  obtained  at  dejDths  of 
40  to  50  feet.  They  are  almost  entirely  through  till,  the  lower  half  being 
a  blue  till. 

At  Prentice  a  coal  shaft  penetrates  85  feet  of  drift,  the  greater  part  of 
which  is  a  blue  till.  In  the  lower  ten  feet  a  sandy  clay  containing-  a  log 
was  passed  thi'ough. 

At  Alexander  wells  are  usually  obtained  at  depths  of  20  to  40  feet,  but 
one  at  the  elevator  reached  a  dejDth  of  95  feet  and  did  not  enter  rock.  Its 
section  is  as  follows: 

Section  oftoell  at  elevator  in  Alexander,  lUinois. 

Peet. 

Loess 10 

Yellow  till 10 

Blue  till  with  thin  saud  beds 75 


724  THE  ILLINOIS  GLACIAL  LOBE. 

A  well  near  Alexander,  on  the  farm  of  Isaac  Tyndall,  was  sunk  to  a 
depth  of  1,000  feet  without  obtaining  a  flow.  Another  well  was  sunk  to 
a  depth  of  320  feet.  Each  of  the  wells  yields  a  small  amount  of  gas, 
which  is  struck  in  Coal  Measures  strata.  The  drift  at  these  wells  is  about 
90  feet  in  depth,  as  follows : 

Section  of  drift  in  Tyndall  well  near  Alexamder,  Illinois. 

Feet. 

Soil  and  yellow  clay - 25 

Gray  pebbly  clay 26 

Blue  clay 25 

Clays  of  variable  color 15 

Total  drift 90 

At  "Waverly  wells  are  20  to  50  feet  in  depth,  and  the  deeper  ones 
enter  rock  near  the  bottom.  The  loess  in  that  vicinity  is  only  6  feet  in 
depth.  The  drift  is  mainly  yellow  till,  though  there  is  blue  till  near  the 
base. 

In  tlie  vicinity  of  Franklin  rock  is  usually  entered  at  about  35  feet, 
but  wells  are  often  obtained  above  the  rock. 

SANGAMON    COUNTY. 
GENERAL   STATEMENT. 

Sangamon  County,  situated  near  the  center  of  the  State,  contains 
Springfield,  the  State  capital,  which  is  also  the  county  seat.  It  has  an  area 
of  860  square  miles.  The  northeastern  portion  of  the  county  is  traversed 
in  a  westward  course  by  the  Sangamon  River,  and  this  stream  with  its 
tributaries  drains  nearly  all  of  the  county.  The  drainage  from  the  western 
and  southern  portions  of  the  county  is  northeastward,  there  being  a  rapid 
descent  in  that  direction.  The  county  is  well  drained,  and  yet  the  valleys 
of  most  of  the  streams  are  very  shallow.  A  coating  of  loess  about  8  feet 
in  average  depth  caps  the  glacial  drift,  and  aids  greatly  in  the  ready 
absorption  of  the  excess  of  rainfall. 

The  drift  is  generally  of  moderate  depth,  the  distance  to  rock  being 
seldom  more  than  50  feet.  Where  it  is  mainly  till,  wells  are  frequently 
sunk  into  the  underlying  Coal  Measures  for  Avater,  the  supph^  from  the  drift 
being  weak.  Tlie  conspicuous  development  of  Sangamon  soil  between  the 
loess  and  till  is  discussed  on  preceding  pages. 


WELLS  OF  CHEISTIAN  COUlJTTY,  ILLINOIS.  725 

INDIVIDUAL    WELLS. 

The  jDiiblic  water  supply  for  the  city  of  Springfield  is  obtained  from 
infiltration  wells  sunk  to  a  depth  of  about  25  feet  on  the  banks  of  the 
Sangamon  River.  Private  wells  are  largely  discontinued,  but  may  be 
obtained  at  depths  of  25  feet  or  less. 

In  the  northwest  part  of  the  county,  near  Pleasant  Plain,  the  drift  is 
60  to  80  feet  in  dejDth,  as  shown  by  coal  shafts,  but  wells  are  usually 
obtained  at  20  to  40  feet. 

In  the  northern  part  of  the  county  the  drift  is  40  to  60  feet  in  depth, 
but  wells  are  usually  obtained  without  entering-  the  rock. 

In  the  eastern  part  several  coal  shafts  and  a  few  of  the  wells  enter  rock 
at  about  60  feet.  At  Illiopolis  rock  is  struck  at  54  feet,  and  at  Dawson  at 
60  feet.  Southeast  from  Illiopolis,  near  the  Sangamon  River,  records  of 
two  wells  were  obtained  which  penetrated  about  80  feet  of  drift. 

In  the  southern  part,  near  Lowder,  although  the  altitude  is  the  highest 
in  the  county,  rock  is  frequently  entered  at  about  20  feet.  This  area  of 
thin  drift  is  a  continuation  of  that  noted  in  southeastern  Morgan  County. 

In  the  western  part  of  the  county  the  distance  to  rock  ranges  from  20 
to  at  least  75  feet.  Near  New  Berlin  the  rock  is  entered  at  40  or  50  feet. 
At  Bates  a  well  at  the  elevator,  70  feet  in  depth,  did  not  reach  rock.  A 
well  at  the  elevator  in  Curran  also  reached  a  dejDth  of  70  feet  without  enter- 
ing rock,  but  within  2  or  3  miles  south  of  Curran  wells  enter  rock  at  20  or 
30  feet. 

CHRISTIAN    COUNTY. 
GENERAL    STATEMENT. 

Christian  County  is  situated  southeast  of  Sangamon  and  has  an  area  of 
710  square  miles,  with  Taylorville  as  the  county  seat.  It  is  drained  chiefly 
by  the  South  Fork  of  Sangamon  River,  which  leads  northwestward  through 
the  county.  -The  main  Sangamon  River  forms  the  north  border  of  the 
county.  The  character  of  the  drainage  and  the  coating  of  loess  are  similar 
to  the  same  features  in  Sangamon  Countj^  already  discussed. 

The  drift  is  seldom  less  than  60  feet,  and  in  places  is  more  than  100 
feet  in  thickness,  and  consists  largely  of  blue  till.  The  occurrence  of  peat 
and  muck  at  the  base  of  the  loess  is  quite  common,  as  indicated  on  page  126. 
Tliroughout  the  county  wells  are  usually  obtained  at  depths  of  20  to  30 


726  THE  ILLINOIS  GLACIAL  LOBE. 

feet.     The  data  concerning'  the  distance  to  rock  are  obtained  largely  tlu'ough 
coal  shafts  and  borings. 

INDIVIDUAL   WELLS. 

At  Mount  Auburn,  which  is  situated  on  a  knoll  in  the  north  part  of  the 
county,  wells  penetrate  a  brown,  sandy  clay  to  a  depth  of  about  30  feet 
before  entering  blue  till.  On  the  bordering  plain  blue  till  is  found  at  20  to 
25  feet,  but  wells  are  usually  obtained  without  entering  it.  The  drift  in 
that  vicinity  is  at  least  80  feet  in  depth. 

Near  the  center  of  the  county,  in  the  vicinity  of  Taylorville,  wells  are 
frequently  found  at  depths  of  only  15  feet,  in  sandy  beds  at  the  base  of  the 
loess.  In  the  city  of  Taylorville,  however,  they  are  usually  sunk  to  depths 
of  20  to  40  feet.  The  public  water  supply  is  from  an  open  well  30  feet  in 
diameter  and  30  feet  in  depth.  The  amount  of  water  is  so  great  in  this 
vicinity  that  much  difficulty  is  experienced  in  sinking  coal  shafts.  The 
Taylorville  coal  shaft  has  the  following  section  of  diift: 

Section  of  drift  in  the  Taylorville  coal  shaft. 

FeoL 

Surface  clay 13 

Sand  and  gravel 24 

White  clay 3 

Black  gummy  clay 4 

Bowlder  clay 17 

Sand  aud  gravel 15 

Sand 15 

Greenish  clay 12 

Clay  and  gravel 12 

Sand  aud  gravel 11 

Total  drift 126 

At  Pana  the  coal  shaft  is  reported  by  Worthen  to  have  penetrated  two 
buried  soils,  but  the  writer  finds  that  his  upper  soil  is  simplv  wood  embed- 
ded in  till.  The  lower  is  a  black  muck.  The  import  of  this  section,  together 
with  similar  sections  at  other  points  has  already  been  discussed  (p.  107  et 
seq.).  The  wells  in  this  city  range  from  18  to  about  50  feet  in  depth.  The 
waterworks  supply  is  from  wells  45  to  48  feet  deep,  in  part  3  inches  and 
in  part  6  inches  in  diameter.  These  wells  afforded,  during  the  season  of 
drought  ill  189,5,  an  average  daily  consumption  of  215,000  gallons.  A 
boring  was  sunk  at  this  city  to  a  depth  of  2,507  feet,  but  found  only  a  weak 
supply  oi'  brackish  water  after  entering  the  rock. 


9 


WELLS  OF  MAOON  COUNTY,  ILLINOIS.  727 

At  Morrisonville  the  public  water  supply  is  obtained  from  large  wells 
excavated  to  a  depth  of  25  or  30  feet.  During  the  drought  of  1894  and 
1895  only  about  300  ban-els  a  day  could  be  obtained  from  this  source, 
where  fully  twice  that  amount  was  needed.  Mr.  H.  N.  Herdman,  chairman 
of  the  waterworks  committee,  estimates  that  private  wells  in  the  village 
have  an  average  yield  of  about  10  barrels  a  day  in  seasons  of  drought. 

At  Palmer  a  coal  shaft  penetrates  60  feet  of  drift,  as  follows : 

Section  of  coal  shaft  at  Palmer,  Illinois. 

Teet. 

Loess  and  yellow  till 16 

Hard  gray  till 22 

Soft  brown  clay ^ 

Sand 10 

Gravel 1 

Pebbly  clay 4 

Total  drift 60 

At  Miller  Station  rock  is  entered  at  about  60  feet,  or  at  nearly  the  same 
elevation  above  tide  as  at  Pana.     The  drift  is  largely  gray  till. 

MACON  COUNTY. 

GENERAL    STATEMENT. 

Macon  County  is  situated  in  the  central  part  of  the  State,  with  Decatur 
as  the  county  seat,  and  has  an  area  of  780  square  miles.  The  Sangamon 
River  traverses  it  nearly  centrally  from  east  to  west,  and  there  are  no  other 
large  streams  within  the  limits  of  the  county.  The  greater  portion  of  the 
county  lies  within  the  limits  of  the  Wisconsin  drift,  the  outer  moraine 
formed  at  the  Wisconsin  stage  of  glaciation  having  a  southward  course 
through  the  western  part  of  the  county.  The  portion  occupied  by  the 
Wisconsin  drift  stands  about  100  feet  above  the  plain  on  the  west,  but  is 
far  less  perfectly  drained.  Not  only  are  drainage  lines  less  perfect,  but  the 
loess,  which  constitutes  so  important  an  absorbent  for  water  in  counties  to 
the  west,  is  absent  or  is  represented  only  by  a  thin  coating,  probably 
drifted  by  the  wind. 

The  thickness  of  the  drift  is  known  at  but  a  few  points,  and  these, 
together  with  sections  of  deep  wells  which  do  not  reach  rock,  indicate  that 
the  average  thickness  of  the  drift  exceeds  100  feet.  The  Wisconsin  drift 
consists  largely  of  a  soft  blue  till,  readily  distinguished  from  the  harder 


t 
728  THE  ILLINOIS  GLACIAL  LOBE. 

gray  or  bine  tills  of  the  earlier  sheets  beneath  it  and  Avhich  extend  over  tlie 
country  to  the  west. 

Tubidar  wells  are  often  sunk  in  the  j^ortion  of  the  county  covered  by 
the  Wisconsin  drift  to  a  depth  of  100  to  150  feet,  and  occasional! v  to 
greater  depths  without  reaching  rock.  A  large  number  of  wells,  llowe^•er, 
are  obtained  from  this  drift  sheet  at  depths  of  but  20  to  40  feet.  On  the 
jjlain  outside  the  limits  of  the  Wisconsin  drift  the  wells  are  often  obtained 
at  but  12  to  15  feet,  and  tliey  seldom  exceed  25  feet  in  depth. 

INDIVIDUAL    WELLS. 

At  Niantic,  on  the  plain  in  the  western  part  of  the  county,  wells  are 
usually  obtained  in  sand  and  gravel  at  a  depth  of  15  feet.  A  coal  shaft  at 
this  village  penetrates  the  following  beds  of  drift : 

Section  of  drift  beds  in  coed  shaft  of  Niantic,  Illinois. 

Feet. 

Soil  and  brown  clay H 

Sand  and  gravel _ 4 

Till  of  grayish  color _ 25 

Hard  blue  till 10 

Soft  clay 15 

Hard  gray  till 10 

Soft  clay  of  brown  color 7 

Total  drift ^2 

At  Hamstown,  on  the  crest  of  the  moraine  east  of  Niantic  and  about 
90  feet  higher,  several  tubular  wells  have  been  sunk  to  depths  ranging  from 
75  to  152  feet.  The  deepest,  at  the  residence  of  Dr.  John  Connelly,  has 
tlie  following  section : 

Feet. 

Yellow  till 15 

Soft  blue  till,  about 100 

Hard  grayish-blue  till 37 

Gravel  and  water  at  bottom. 

Total 152 

In  several  instances  the  wells  near  Harristown  appear  to  obtain  their 
supjily  from  the  base  of  the  Wisconsin  drift,  just  below  the  soft  blue  till,  at 
a  depth  of  100  to  110  feet.  The  few  which  are  sunk  deeper  usually  enter 
a  harder  till,  as  in  the  section  just  noted.  East  from  Harristown,  toward 
Decatur,  the  wells  are  often  sunk  to  depths  of  85  to  110  feet,  mainlv  through 
a  soft  blue  till.  The  elevation  is  a  few  feet  lower  than  on  the  crest  of  the 
moraine  at  Hamstown,  and  the  wells  probably  reacli  tlie  bottom  of  the 
Wisconsin  drift. 


WELLS  OF  MOULTEIE  COUNTY,  ILLINOIS.  729 

The  city  of  Decatur  obtains  its  public  water  suppl}^  by  pumping  from 
the  Sang-amon  River.  The  city  engineer  reports  that  the  wells  of  that  city 
obtain  their  strongest  supply  of  water  at  a  depth  of  about  100  feet  in  beds  of 
gravel  below  blue  clay,  and  that  the  water  from  these  -wells  will  rise  within 
20  feet  of  the  top.  He  estimates  the  capacity  of  a  good  well  to  be  about 
20  barrels  a  day.  Coal  borings  at  Decatur,  reported  in  the  Geology  of 
Illinois,  enter  rock  in  one  instance  at  110  feet  and  in  another  at  140  feet. 
The  section  of  the  air  shaft,  taken  from  the  Geology  of  Illinois,  which 
appears  on  page  204,  indicates  the  variable  structure  of .  the  di-ift.  .The 
shaft  is  located  near  the  Sangamon  River  Ijluff. 

At  Maroa,  in  the  north  part  of  the  county,  the  strongest  wells  are 
about  100  feet  in  depth,  in  gravel  below  till.  This  village  has  waterworks, 
recently  constructed,  which  obtains  its  supply  from  gravel  at  a  depth  of  85 
to  100  feet.  At  the  neighboring  villag-e  of  Forsj^the  several  good  wells  are 
obtained  at  35  to  45  feet. 

At  Macon  a  well  120  feet  in  depth  furnishes  the  public  water  supply. 
It  terminates  in  gravel  below  a  thick  sheet  of  till,  and  the  well  is  practically 
inexhaustible.  Water  rises  within  60  feet  of  the  surface,  and  it  is  stated 
by  residents  that  the  water  rose  to  that  level  in  less  than  five  minutes  after 
the  water  bed  was  struck. 

The  well  at  Blue  Mound  from  which  the  public  water  supply  is 
pumped  was  sunk  to  a  depth  of  213  feet  without  reaching  rock,  mainly 
tln'ough  a  hard  blue  till.  As  this  village  stands  on  the  plain  outside  the 
Wisconsin  drift  sheet,  the  great  thickness  of  drift  here  ^jenetrated  belongs 
to  an  earlier  stage  of  glaciation.  The  principal  part  of  the  water  is  obtained 
within  40  feet  of  the  surface,  and  wells  in  that  vicinity  are  15  to  40  feet 
deep. 

MOULTRIE    COUNTY. 
GENERAL    STATEMENT. 

Moultrie  County  is  situated  southeast  of  Macon,  in  the  east-central 
part  of  the  State,  with  Sullivan  as  the  county  seat,  and  has  an  area  of 
340  square  miles.  The  Kaskaskia  River  crosses  the  southeastern  part  in 
a  westward  course,  and  most  of  the  county  is  tributary  to  that  stream. 
Much  of  the  surface  is  flat  and  poorly  drained,  the  county  being  situated 
within  the  limits  of  the  Wisconsin  drift,  where  drainage  lines  are  generally 
immature. 


730  THE  ILLINOIS  GLACIAL  LOBE. 

The  thickness  of  drift  is  known  only  at  the  village  of  Sullivan,  where 
it  is  about  200  feet.  Borings  in  neighboring  counties  also  jDenetrate  nearly 
as  great  an  amount  of  drift.  It  therefore  seems  probable  that  the  thickness 
at  Sullivan  is  not  much  above  the  average  for  the  county.  Wells  in  this 
county  enter  a  soft  blue  till  at  10  or  15  feet,  which,  like  that  of  the  neigh- 
boring counties,  Piatt  and  Macon,  belongs  to  the  Wisconsin  drift.  It  prob- 
ably extends  to  the  level  of  the  plain  outside  the  Wisconsin  di-ift  sheet, 
which  is  nearly  100  feet  lower  than  the  general  elevation  of  this  county. 
Few  records  of  wells  were  obtained,  though  it  was  ascertained  that  wdiile 
wells  are  usually  but  30  or  40  feet  deep,  not  a  few  are  sunk  to  depths  of 
over  100  feet. 

INDIVIDUAL    WELLS. 

At  Sullivan  the  strongest  wells  are  obtained  at  a  depth  of  100  to  125 
feet  in  sand  beds  below  till,  and  the  waterworks  are  supplied  from  a  well  of 
this  class.  A  coal  boring  at  or  near  Sullivan,  made  by  Mr.  John  Patterson, 
is  reported  to  have  struck  a  soft  sandstone  at  about  200  feet,  but  a  well 
boring  at  Sullivan,  made  by  Mr.  Patterson,  is  reported  in  the  Geology  of 
Illinois  to  have  reached  a  depth  of  210  feet  without  entering  rock  and  to 
have  terminated  in  sand  below  clay.  Veins  of  water  were  struck  at  15  feet, 
105  feet,  and  180  feet.  The  last  vein  struck  has  a  head  15  feet  below  the 
surface. 

At  Dalton  there  is  a  village  well  110  feet  in  depth,  which  obtains  its 
main  supply  from  about  70  feet.^  Several  wells  in  this  vicinitv  are  70 
to  85  feet  in  depth  and  a  few  about  100  feet.  They  reach  the  base  of  the 
Wisconsin  drift  at  about  65  feet,  below  which  there  is  sandy  material  often 
associated  with  a  black  mucky  soil.  Beneath  this  sandv  material  is  a 
harder  till  than  the  Wisconsin.  The  deepest  wells  in  that  vicinity  are 
150  feet,  and  none  strike  rock. 

At  Bethany  wells  are  often  sunk  to  a  depth  of  70  feet  before  reaching 
a  good  supply  of  water.  The  Wisconsin  drift  here  is  only  about  40  feet, 
beneath  wliich  there  is  a  greenish  clay  associated  with  a  black  muck.  This 
is  underlain  by  a  hard  till,  in  which  there  are  gravelly  beds  yielding  water. 
The  deepest  wells  are  140  feet  and  do  not  enter  rock. 

'The  Manual  of  American  WaterworUs  (1897)  reports  that  the  public  water  supply  at  Dalton 
is  obtained  from  a  shallow  well  retiniriug  a  pump  but  22  feet  in  length.  This  is  evidently  a  mistake, 
since  no  wateiworks  had  been  constructed  or  were  contemplated  at  the  time  of  my  visit  in  June.  1897. 


WELLS  OF  DOUGLAS  COUNTY,  ILLINOIS.  731 


DOUGLAS  COUNTY. 
GENERAL    STATEMENT. 


Douglas  County  is  situated  in  the  east-central  part  of  the  State,  with 
Tuscola  as  the  county  seat,  and  it  has  an  area  of  410  square  miles.  Its 
western  portion  is  crossed  in  a  southward  course  by  the  Kaskaskia  River, 
and  the  east-central  portion  by  the  Embarras  River.  The  surface  is  gener- 
ally very  level  and  imperfectly  drained,  except  on  the  immediate  borders 
of  the  streams  just  mentioned.  A  small  drift  ridge  belonging  to  the  Cham- 
paign system  traverses  the  northeast  part  of  the  county,  but  it  has  a  g-eneral 
relief  of  only  20  to  30  feet  above  the  bordering  plain.  A  similar. small 
ridge  crosses  the  southeast  corner  of  the  county.  The  surface  of  these 
ridges  is  nearly  as  smooth  as  that  of  the  bordering  plains,  and  is  imperfectly 
drained. 

The  thickness  of  the  drift  in  this  county  has  been  ascertained  at  but 
one  point,  Tuscola,  where  one  well  entered  rock  at  174  feet  and  another 
at  179  feet.  But  at  Oakland,  just  across  the  county  line,  in  Coles  County, 
rock  is  entered  at  only  50  feet.  The  drift,  like  that  of  the  counties  to  the 
west,  just  discussed,  consists  mainly  of  a  soft  blue  till  as  far  as  wells  have 
penetrated.  Iia  the  wells  at  Tuscola  the  drift  was  in  the  main  a  blue  till. 
Wells  60  to  75  feet  in  depth  are  common  in  this  county,  and  a  few  have 
been  sunk  to  depths  of  100  feet  or  more. 


INDIVIDUAL    WELLS. 


At  Areola  the  public  water  supply  is  from  wells  about  50  feet  in  depth, 
and  records  of  several  wells  were  obtained  in  the  vicinity  of  that  village 
which  have  a  similar  depth.  Two  wells  a  few  miles  southeast  of  Areola 
are  reported  to  have  entered  a  swampy  muck  below  blue  till  at  about  50 
feet,  and  beneath  this  a  till  was  found  harder  than  that  above  the  muck. 
One  well  at  Morris  Bradford's  reached  a  depth  of  68  feet  and  one  at 
E.  Bradford's  a  depth  of  75  feet. 

At  Tuscola  a  deep  well  has  been  sunk  with  a  view  to  obtaining  artesian 
water  for  the  waterworks,  but  at  last  reports  the  well  was  incomplete  and 
waterworks  had  not  been  established.^  The  wells  in  the  vicinity  of  Tuscola 
are  obtained  at  a  depth  of  about  30  feet,  but  none  are  considered  of  suffi- 
cient strength  to  supply  the  waterworks. 


'  Manual  of  American  Waterworks,  1897. 


732  THE  ILLINOIS  GLACIAL  LOBE. 


EDGAR  COUNTY. 
GENERAL  STATEMENT. 


Edo'ar  Oountv  is  situated  near  the  middle  of  the  east  boundarv  of  the 
State  aud  lias  an  area  of  630  square  miles,  with  Paris  as  the  county  .seat. 
It  is  crossed  by  no  large  streams,  the  di-ainage  being  entirely  through  small 
creeks.  Those  in  the  eastern  part  drain  eastward  to  the  Wabash,  those  in 
the  western  part  are  tril^utary  to  the  Embarras,  while  the  drainag-e  of  the 
southern  portion  is  divided  between  the  tributaries  of  the  Embarras  and 
small  streams  leading  directly  to  the  Wabash. 

The  northern  part  of  the  county  is  occupied  by  the  Champaign 
morainic  system,  while  the  southern  portion  is  crossed  by  the  Shelbvville 
morainic  system.  Between  these  morainic  systems  there  is  a  verv  flat  area 
dotted  with  occasional  low  knolls  or  ridges  of  drift.  South  of  the  limits 
of  the  Wisconsin  drift  there  is  a  low  plain  which  touches  the  borders  of 
this  county  and  which  is  markedly  more  eroded  than  the  more  elevated 
plain  north  of  the  outer  moraine,  a  feature  which  testifies  to  its  long-er 
exposure  to  agencies  of  erosion. 

The  drift  of  the  moraines  and  the  plain  between  them  consists  largelv 
of  a  soft  blue  till,  thoug'h  portions  of  the  outer  moraine  have  a  gravelly 
constitution.  The  plain  outside  the  outer  moraine  is  underlain  by  a  harder 
till  than  that  forming  the  body  of  the  moraine.  It  is  also  capped  by  a  silt 
which  is  correlated  with  the  loess,  but  the  moraine  and  district  to  the  north 
are  nearly  free  from  silt  capping. 

The  thickness  of  the  drift  along  each  of  the  moraines  is  100  feet  or 
more,  but  on  the  plain  between  the  moraines  rock  is  in  places  entered  at  50 
feet  or  less,  the  drift  being  much  thinner  than  in  counties  to  the  west.  The 
rock  siii'face  appears  to  be  generally  higher  in  Edgar  County  than  in  neigh- 
boring counties  on  the  west. 

Wells  are  generally  obtained  in  this  county  at  depths  of  20  to  40  feet 
and,  so  far  as  ascertained,  A-ery  few  exceed  60  feet.  Those  which  enter 
rock  usually  find  water  within  a  few  feet.  Tlie  majority,  however,  obtain 
their  supph^  above  the  rock. 

INDIVIDIAL    WELLS. 

The  public  water  supply  at  Paris  is  olnained  from  a  well  60  feet  deep, 
which  terminates  in  gravel  below  till.     The  private  wells  in  the  city  aud 


WELLS  OF  OLARK  COUNTY,  ILLINOIS.  733 

vicinity  are  usually  obtained  at  depths  of  20  to  40  feet.  A  boring  at 
Sanford,  near  the  State  line,  east  of  Paris,  whose  section  is  given  on  page 
201,  entered  rock  at  147  feet. 

At  Dudley  wells  are  obtained  at  about  25  feet  and  are  largely  tln-ough 
a  sandy  drift.  Between  Dudley  and  Kansas  and  also  to  the  north  of  the 
latter  village  wells  are  reported  to  have  passed  through  a  soil  below  till  at 
35  to  40  feet. 

At  Kansas  wells  are  usually  20  to  25  feet  and  occasionally  40  feet  in 
depth.  They  are  obtained  in  gravel  below  blue  till.  Good  wells  are  esti- 
mated to  yield  about  30  barrels  of  water  a  day. 

Near  Isabel  wells  occasionally  reach  a  depth  of  60  or  60  feet  without 
entering  rock.  The  majority  of  wells,  however,  are  much  shallower.  A 
short  distance  east  of  Isabel  rock  is  encountered  at  a  depth  of  only  25  feet, 
and  wells  in  the  central  and  eastern  parts  of  the  county  not  infrequently 
enter  rock  at  25  feet  or  less. 

On  the  plain  outside  the  Wisconsin  drift  wells  are  usually  obtained  at 
about  30  feet  and  seldom  enter  the  rock.  They  are  largely  through  a  hard 
till. 

CLARK  COUNTY. 
GENERAL  STATEMENT. 

Clark  County  is  situated  on  the  eastern  border  of  the  State,  immediately 
south  of  Edgar,  a  portion  of  its  east  border  being  formed  by  the  Wabash 
River.  It  has  an  area  of  510  square  miles,  with  Marshall  as  its  county  seat. 
The  eastern  portion  of  the  county  drains  directly  to  the  Wabash,  but  the 
western  half  is  drained  southward  through  Hickory  Creek,  a  tributary  of 
the  Embarras.  The  outer  moraine  of  the  Wisconsin  drift  covers  a  few 
square  miles  in  the  northwest  corner  of  the  county.  Aside  from  this  the 
drift  of  the  county  belongs  to  the  earlier  stages  of  glaciation.  Although 
the  surface  was  originally  very  level,  drainage  lines  are  sufficiently  well 
developed  to  remove  the  surplus  rainfall  more  rapidly  than  on  the  flat  areas 
occupied  by  the  Wisconsin  drift.  The  drift  has  a  capping  of  the  compact 
phase  of  the  loess,  called  white  clay,  whose  depth  is  but  5  or  6  feet.  As 
previously  indicated,  this  clay  is  separated  from  the  underlying  till  by  a 
black  soil. 

The  drift  of  this  county  is  largely  a  hard  till  which  is  brownish  yellow 
at  top,  but  changes  to  a  greyish  blue  color  at  a  depth  of  15  or  20  feet. 


734  THE  ILLINOIS  GLACIAL  LOBE. 

Wells  are  usually  of  sufficient  strength  for  household  or  farm  use,  but  Mr. 
J.  T.  Lafferty,  of  Martinsville,  an  old  i-esident  of  the  county,  states  that  the 
strongest  wells  seldom  yield  more  than  10  barrels  a  day,  and  a  large  number 
will  not  afford  more  than  one  "barrel.  Wells  are  us^ially  obtained  at  a 
depth  of  15  or  20  feet  from  pockets  or  thin  beds  of  gravel  or  sand  asso- 
ciated with  the  till.  In  portions  of  the  county  wells  have  been  sunk  to 
depths  of  40  feet  or  more,  and  such  wells  usually  obtain  their  supply  from 
gravel  below  blue  till.  In  the  vicinity  of  Marshall,  however,  sandstone  is 
entered  at  about  20  feet,  and  wells  are  obtained  after  penetrating  it  a  few 
feet. 

INDIVIDUAL    WELLS. 

The  wells  at  Marshall  which  enter  sandstone  are  estimated  to  yield,  in 
some  cases,  100  barrels  a  day,  and  many  of  them  are  but  25  feet  in  depth. 

In  the  vicinity  of  Martinsville  a  few  wells  have  been  sunk  to  a  depth 
of  70  or  80  feet,  but  they  are  usually  obtained  at  15  or  20  feet. 

At  Casey  the  deepest  wells  are  about  100  feet,  but  the  great  majority 
are  between  18  and  25  feet  in  depth. 

On  the  Wabash  bottoms,  in  the  southeast  part  of  the  county,  wells  are 
usually  obtained  at  about  the  level  of  the  river.  On  the  higher  terraces 
they  need  to  be  sunk  50  or  60  feet.     They  penetrate  fine  gravel  or  sand. 

COLES  COUNTY. 
GENERAL    STATEMENT. 

Coles  County  is  situated  in  the  east-central  part  of  the  State,  with 
Charleston  as  the  county  seat,  and  has  an  area  of  520  square  miles.  The 
Kaskaskia  River  passes  southwestward  across  its  northwest  corner,  and  the 
Embarras  River  passes  southward  through  the  eastern  part  of  the  county. 
The  greater  part  of  the  county  is  tributary  to  the  latter  stream,  but  is 
imperfectly  drained,  like  the  neighboring  counties  on  the  north  and  west 
already  discussed.  The  Shelbyville  morainic  system  crosses  the  southern 
part  of  the  county  in  an  east-to-west  course,  lea^'ing  but  a  few  square 
miles  in  the  extreme  southeast  and  southwest  corners  outside  its  limits. 
'I'liis  morainic  system  has  a  breadth  of  5  or  (>  miles  and  a  relief  of  75  to 
100  feet  abo\n'  the  jjlain  south  of  it.  It  stands  only  30  to  50  feet  above 
the  plain  on  tlie  north. 


WELLS  OF  COLES  COUNTY,  ILLINOIS.  735 

The  Wisconsin  drift  sheet  in  this  county,  as  in  neighboring  counties 
already  discussed,  consists  largely  of  a  soft  blue  till,  while  the  underlying 
sheet  of  drift  is  a  harder  till.  Along  the  Embarras  River  there  are  expos- 
ures of  the  harder  till  beneath  the  Wisconsin  drift,  and  this  harder  till  is 
capped  by  a  white  clay,  as  in  the  disti-icts  outside  the  limits  of  the 
Wisconsin  di'ift. 

In  the  eastern  portion  of  the  county  rock  is  occasionally  entered  at  45 
to  50  feet,  and  is  exposed  extensively  along  the  Embarras  River  in  the 
southern  part  of  the  county.  The  thickness  in  the  western  half  of  the 
county  is  greater,  being  in  places  not  less  than  150  feet.  Wells  are  usually 
obtained  without  entering  the  rock,  .and  in  the  western  part  of  the  county 
but  few  reach  the  bottom  of  the  Wisconsin  sheet  of  drift. 

INDIVIDUAL    WELLS. 

At  Oakland,  in  the  northeast  part  of  the  county,  the  wells  are  usually 
about  20  feet  in  depth.  But  a  well  at  the  mill  reached  a  depth  of  120  feet, 
entering  rock  at  50  feet. 

Northwest  from  Fairgrange  several  wells  have  been  sunk  to  depths  of 
60  to  120  feet  without  entering  rock.  They  usually  pass  from  a  soft  to  a 
hard  till  at  a  depth  of  50  or  60  feet.  This  is  thought  to  be  the  depth  of 
the  Wisconsin  drift  sheet  in  that  locality. 

At  Charleston  the  waterworks  are  supplied  b}^  pumping  from  the 
Embarras  River.  Wells  are  usually  obtained  from  sand  and  gravel  below 
till  at  a  depth  of  20  to  40  feet.  A  well  in  the  northern  part  of  this  city 
reached  a  depth  of  127  feet  without  entering  rock,  but  a  boring  for  oil 
made  some  years  since  is  reported  in  the  Geology  of  Illinois  to  enter  rock 
at  55  feet.     The  section  of  drift  is  as  follows : 

Section  of  boring  at  Charleston,  Illinois. 

Feet. 

Soil  and  yellow  clay 18 

Sand  and  gravel 6 

Blue  clay 16 

Bowlder  clay 15 

Total  drift 55 

At  Mattoon  the  public  water  supply  is  obtained  from  sand  and  gravel 
below  till  at  a  depth  of  60  to  70  feet.  The  private  wells  in  this  village  are 
usually  obtained  at  15  to  30  feet.  A  coal  boring  is  reported  to  enter  rock 
at  about  100  feet  (see  p.  202). 


736  THE  ILLIXOIS  GLACIAL  LOBE. 

At  Lerna,  which  is  situated  on  the  crest  of  the  outer  moraine  of  the 
Wisconsin  di'ift,  wells  have  occasionally  reached  a  depth  of  100  feet  with- 
out enterino-  rock.  One  made  by  Mr.  Todd,  one-half  mile  northwest  of  the 
village,  and  another  b}*  Mr.  Farris  in  section  11,  each  have  a  depth  of  100 
feet  and  are  mainly  through  blue  till. 

A  well  near  Farmington,  made  by  Mr.  T.  Allison,  reached  a  depth  of 
132  feet  without  entering  rock,  mainly  through  blue  till.  East  from  this 
well,  in  the  Embarras  Valley,  rock  is  exposed  up  to  a  level  within  75  feet 
of  that  of  the  well  mouth. 

At  Diona,  on  the  plain  outside  the  Wisconsin  drift  sheet,  wells  are 
(jbtained  at  a  depth  of  only  12  feet,  and  are  mainly  through  gravel. 

CUMBERLAND  COUNTY. 
GENERAL    STATEMENT. 

Cumberland  County  is  situated  south  of  Coles,  in  the  east-central  part 
of  the  State,  with  Toledo  as  the  county  seat,  and  it  has  an  area  of  350 
square  miles.  The  Embarras  River  leads  southward  through  the  east- 
central  part  of  the  county  and  drains  its  eastern  half.  The  western  part  is 
tributary  to  the  Little  Wabash  River,  which  leads  southward  near  the  county 
line.  This  dounty  is  strikingly  in  contrast  with  Coles  County  on  account  of 
the  absence  of  the  Wisconsin  di-ift  sheet,  which  covers  only  a  few  square 
miles  on  its  north  border.  Its  surface  is  covered  with  the  deposit  of  white 
clay  which  is  so  prevalent  in  southern  Illinois  outside  the  limits  of  the  Wis- 
consin drift.  This  clay  absorbs  water  so  slowly  on  the  interflu-sdal  tracts  of 
Cumberland  County  that  most  of  the  water  not  removed  by  the  sti'eams  is 
evaporated.  The  surface  is  very  level,  and  this  feature  works  to  the  disad- 
vantage of  the  development  of  drainage  systems.  There  is,  however,  a 
much  more  mature  system  of  drainage  here  than  on  the  Wisconsin  drift 
sheet  in  Coles  County,  a  feature  wliich  points  strongly  to  the  comparative 
freshness  of  the  latter  sheet  and  recency  of  its  deposition. 

The  thickness  of  the  drift  is  known  at  but  a  few  points,  and  these  are 
in  the  vicinity  of  the  Embarras  River.  In  places  the  rock  occurs  along 
this  river  at  a  level  only  30  or  40  feet  below  the  level  of  the  uplands,  but 
in  other  places  Avells  near  the  river  show  that  the  drift  extends  fully  50  feet 
below  the  bed  of  the  stream,  or  over  100  feet  below  the  level  of  the  uplands. 
Beneath  the  white  clay,  which  is  usuall\'  l>ut  4  or  6  feet  in  thickness,  there  is 


WELLS  OF  CUMBEELAND  COUNTY,  ILLINOIS.  737 

a  black  soil  formed  at  tlie  surface  of  the  till.  The  body  of  the  di-ift  appears 
to  be  generally  a  hard  till  oxidized  to  a  yellowish  color  for  a  depth  of  about 
12  to  15  feet,  beneath  which  it  has  a  blue-gray  color. 

The  wells  in  this  county,  like  those  in  Clark  County,  on  the  east,  are 
usually  of  sufficient  capacity  to  siipply  the  needs  of  the  residents,  though 
they  seldom  yield  more  than  10  barrels  a  day.  The  till  apparently  has 
only  local  inclusions  of  sand  and  gravel,  seldom  of  suiiicient  amount  to 
furnish  strong  wells.  The  depth  of  wells  rarely  exceeds  40  feet,  and  the 
majority  are  only  10  or  15  feet.  It  is  probable  that  they  are  largely  filled 
from  the  well  mouth  by  water  running  into  them  from  the  surface  of  the 
ground  during-  rainy  seasons. 

INDIVIDUAL    WELLS. 

At  Toledo  the  strongest  wells  are  obtained  at  about  60  feet  from  gravel 
below  till.  At  the  bend  of  the  Embarras  River,  about  5  miles  northeast  of 
this  village,  two  wells  situated  on  the  terrace  about  20  feet  above  the  river 
are  67  and  71  feet  in  depth.  They  each  penetrate  about  20  feet  of  gravel, 
beneath  which  they  are  entirely  in  sand  and  do  not  strike  rock.  At  the 
bluff  of  the  river,  east  of  these  wells,  the  following  section  is  exposed, 
which,  it  will  be  observed,  is  entirely  different  from  the  sections  of  the  wells : 

Section  of  bluffs  of  Embarras  River,  near  Toledo,  Illinois. 

Feet. 

White  clay 4 

Soil  and  pale  clayey  snbsoil 5 

Brown  till 10 

Gray  till 30 

At  Greenup  the  wells  are  usually  obtained  near  the  base  of  the  drift, 
at  a  depth  of  about  30  feet.  The  rock  in  the  vicinity  of  Grreenup  stands  at 
an  elevation  nearly  50  feet  above  the  Embarras  River. 

At  Neoga,  on  the  west  border  of  the  county,  wells  are  usually  obtained 
at  about  15  feet.  A  boring  for  coal  is  reported  to  have  entered  rock  at  less 
than  40  feet,  there  being-  a  bed  of  coal  at  that  depth. 

SHELBY  COUNTY. 
GENERAL    STATEMENT. 

Shelby  County  is  situated  southeast  of  the  center  of  the  State,  imme- 
diately west  of  Cumberland  and  Coles  counties.     It  has  an  area  of  776 

MON  XXXVIII 47 


738  THE  ILLINOIS  GLACIAL  LOBE. 

square  miles,  witli  Shelbyville  as  the  county  seat.  The  Kaskaskia  River 
traverses  the  county  in  a  north-and-south  direction  and  drains  nearh"  all  its 
surface.  A  small  area  in  the  southeast  part  is  tributary  to  the  Little  Wa'.jash, 
and  the  northwest  corner  of  the  county  is  tributary  to  the  Sang-anion  River. 
The  Shelbyville  moraine  passes  across  the  northeast  part  of  the  county 
making  an  abrupt  turn  at  the  city  of  Shelbyville  from  a  westward  to  a 
northward  course. 

The  portion  of  the  cormty  outside  the  Shelb}'ville  moraine  is  generally 
plane,  but  the  west  part  of  the  county  is  dotted  with  knolls  of  drift,  some 
of  which  reach  a  height  of  over  100  feet  and  many  are  at  least  50  feet. 

In  the  portion  of  the  county  occupied  by  the  Wisconsin  drift  there  is 
a  sheet  of  soft  blue  till  50  to  100  feet  or  more  in  depth,  covering  the 
harder  till,  which  extends  into  the  outlying  districts.  Exj^osures  of  the 
hard  till  beneath  the  Wisconsin  drift  are  to  be  seen  along  the  Kaskaskia 
River  in  the  Adcinity  of  Shelbyville.  There  are  also  along  the  stream  near 
Shelbyville  exposm-es  of  the  white  clay  which  covers  the  hard  till. 

The  drift  outside  the  Wisconsin  sheet  consists  usually  of  till ;  but  some 
of  the  knolls  and  ridges  contain  a  large  amount  of  gravel  or  sand.  Rock  is 
often  entered  in  tliis  district  at  a  depth  of  50  feet  or  less,  except  on  the  drift 
knolls  and  ridges,  where  the  distance  to  rock  is  usually  increased  by  the 
measure  of  the  height  of  the  knoll  or  ridge. 

The  wells  are  usually  obtained  without  entering  rock.  Those  on  the 
Wisconsin  drift  are  frequently  sunk  to  depths  of  75  or  100  feet,  but  those 
on  the  older  sheet  outside  the  limits  of  the  Wisconsin  drift  seldom  exceed 
30  feet. 

INDIVIDUAL   WELLS. 

At  Moweaqua,  on  the  plain  outside  the  Wisconsin  drift,  in  the  north- 
west part  of  the  county  a  coal  shaft  penetrates  65  feet  of  diift.  The  u})per 
22  feet  is  a  comparatively  soft  clay,  but  the  remainder  is  a  ver}-  hard  blue 
till.  A  well  in  jirocess  of  excavation  at  the  time  the  writer  was  there 
exposed  the  following  section: 

Section  <>/'  ircll  at  Moweaqua,  lUiiwifi. 

•  Feet. 

Lochs  or  pebbleleas  yellow  silt 8 

Yellow  cliiy  witli  a  few  fine  pebbles 7 

Deeply  oxidizeil  till,  very  i)obbly 9 

Hani  blue  till  at  bottom. 


WELLS  OF  SHELBY  COUNTY,  ILLINOIS.  739 

The   Mauual  of  American  Waterworks,  1897,  reports  that  the  public 
water   supply  at  Moweaqua  is   obtained  from  wells,  but  the  depth  is  not 


given. 


iVt  Tower   Hill  a  coal  boring-  enters  rock  at  60  feet.     Drift  knolls  in 


'to 


this  \dllage  rise  about  60  or  75  feet  above  the  level  of  the  ground  at  the 
point  where  this  boring-  was  made.  The  wells  in  the  vicinit}'  of  Tower 
Hill  are  usually  obtained  at  20  feet  or  less,  from  beds  of  sandy  clay  over- 
lying a  hard  blue  till. 

The  public  water  supply  at  Shelbyville  is  pumped  from  the  Kaskaskia 
River.  Wells  are  usually  obtained  at  depths  of  30  to  50  feet  from  sand 
below  till;  in  some  cases  they  are  obtained  at  the  base  of  the  Wisconsin 
drift. 

At  Cowden,  near  the  south  border  of  the  county,  wells  are  usually 
obtained  at  about  20  feet,  just  above  the  hard  blue  till.  Rock  is  struck  at 
40  or  50  feet  An  exposure  on  the  Kaskaskia  bluffs,  near  Cowden,  has  the 
following  section: 

Section  of  bluffs  of  Kashashia  River ^  near  Cowden,  Illinois. 

Feet. 

White  clay 5 

Yellow  clay  with  a  few  pebbles 3 

Reddish-brown  sandy  till 6-8 

Yellow  till,  blue  in  places 10-15 

Hard  blue  till 20 

Coal  Measures  shale  at  base  of  blutf. 

Total  drift 45 

At  Stewardson,  in  the  southeast  part  of  the  county,  wells  are  usually 
obtained  at  20  to  40  feet  without  entering-  rock,  and  similar  conditions  occur 
at  Strasburg. 

At  the  village  of  Windsor,  which  is  located  on  the  Shelbyville  moraine, 
the  village  well  penetrates  90  feet  of  soft  till,  apparently  belonging  to  the 
Wisconsin  drift,  beneath  which  there  is  a  harder  till  with  sandy  matrix. 
Water  was  obtained  in  sand  at  a  depth  of  127  feet.  Several  prospect  bor- 
ings have  been  made  by  Mr.  Jerry  Linn^dlle  at  this  village,  which  have 
reached  depths  ranging  from  120  to  170  feet  without  entering  rock.  Gas 
was  found  in  sand  at  115  to  120  feet,  and  beneath  this  at  about  135  feet  a 
black  muck  was  penetrated.  Whether  this  muck  was  formed  in  a  valley 
bottom  in  a  stage  just  before  the  Wisconsin  drift  was  deposited  or  is  sepa- 
rated from  the  Wisconsin  by  a  glacial  deposit  of  greater  age  is  not  made 


740  THE  ILLINOIS  (ILAOIAL  LOBE. 

clear  by  the  records  of  these  borings.  There  appears,  however,  to  be  a 
deposit  of  sand  extending  from  the  base  of  the  Wisconsin  till  sheet  down 
to  the  bed  of  muck. 

At  the  village  of  Findlay,  in  the  north  part  of  this  county,  several  gas 
wells  have  been  obtained  at  shallow  depths,  ranging  from  45  feet  to  about 
150  feet.  One  well  only  45  feet  in  depth  has  furnished  gas  for  a  period  of 
five  years  in  sufficient  amount  to  supply  three  stoves.  Some  of  tlie  wells 
pass  through  a  thin  bed  of  rock  before  obtaining  gas,  while  others  obtain  it 
in  the  drift.  The  pressure  is  estimated  to  be  about  12  pounds  per  square 
inch  in  the  wells  now  in  use,  though  in  some  cases  a  stronger  pressure  may 
be  found  since  some  have  not  been  tested  with  a  gauge. 

MONTGOMERY  COUNTY. 
GENERAL   STATEMENT. 

Montgomery  County  is  situated  in  the  south-central  part  of  the  State, 
with  Hillsboro  as  the  county  seat,  and  has  an  area  of  702  square  miles. 
The  drainage  is  mainly  southward  through  the  several  headwater  forks  of 
Shoal  Creek,  a  tributary  of  the  Kaskaskia  River.  The  extreme  noi-th 
border  of  the  county  is  tributary  to  the  Sangamon  River.  There  are 
narrow  strips  with  flat,  rather  imperfectly  drained  surface  on  the  divide 
between  Shoal  Creek  and  streams  flowing  north  or  west;  but  the  greater 
part  of  the  county  has  good  drainage.  The  belts  of  knolls  and  ridges  noted 
in  southwestern  Shelby  County  cross  the  eastern  and  central  portions  of 
Montgomery  County,  and  also  occur  at  a  few  places  in  the  southern  part  of 
the  county.  The  best  defined  belt  is  in  the  northeastern  part,  immediately 
east  of  Witt,  Nokomis,  and  Ohlman.  A  ridge  there  rises  to  a  height  of 
nearly  100  feet  above  the  bordering  plains,  and  is  maintained  continuously 
for  several  miles. 

On  the  plane  portions  of  the  county  a  hard  blue  till  is  usually  entered 
at  15  or  20  feet,  after  penetrating  beds  of  loess  and  yellow  till.  Many  of 
the  wells  are  obtained  above  this  blue  till.  On  the  knolls  and  ridges  the 
distance  to  the  l)lue  till  is  apparently  greater  than  on  the  plains.  A  few 
wells  have  entered  it  at  about  40  feet,  after  penetrating  a  series  of  day, 
sand,  and  gravel  beds  of  brown  or  yellow  color.  In  a  few  places  on  the 
plain  the  drift  has  been  found  to  have  a  thickness  of  more  than  100  feet. 
On  the  prominent  knolls   and  ridges   it   probably   exceeds   that  amount. 


WELLS  OP  MONTGOMERY  COUNTY,  ILLINOIS.  '  741 

Rock  is  often  entered  at  50  to  75  feet,  and  is  exposed  along-  the  streams  at 
a  similar  level  below  the  upland  plain.  Occasionally  the  thickness  of  the 
drift  is  but  10  or  20  feet,  as  at  Harvel  and  Witt,  noted  below. 

INDIVIDUAL    AA^ELLS. 

At  Thomasville,  in  the  extreme  north  part  of  the  county,  the  wells 
enter  rock  at  a  depth  of  about  30  feet,  but  are  usually  obtained  near  the 
base' of  the  drift.     At  Harvel  rock  is  entered  at  14  to  20  feet. 

At  Nokomis,  in  the  eastern  part  of  the  county,  the  drift  is  about  100 
feet  in  depth.  The  Manual  of  American  Waterworks  reports  that  the  public 
water  supply  is  obtained  from  di-iven  wells,  but  the  depth  is  not  given.  In 
the  vicinity  of  Witt,  a  few  miles  south  of  Nokomis,  rock  is  entered  at  about 
10  feet,  but  wells  are  obtained  without  difficulty  near  the  top  of  the  rock. 

At  Hillsboro  the  public  water  supply  is  obtained  from  springs.  Wells 
are  usually  obtained  at  depths  of  18  to  25  feet  just  above  the  blue  till. 
They  occasionally  reach  a  depth  of  60  feet.  A  coal  boring  made  near  this 
city  shows  a  complex  series  of  di'ift  beds,  as  follows: 

Section  of  coal  horing  near  Millshoi-o,  Illinois. 

Feet. 

Pale  silt  and  pebbly  browu  clay 14 

Bluish-gray  till  ..- 23 

Sand 1 

Blue-graj'  till 16 

Yellow  clay 7 

Sand  and  gra vf  1 20 

Blue  till _ 26 

Sand  and  gravel 16 

Total  drift ^is 

In  the  vicinit}"  of  Butler  rock  is  struck  at  about  50  feet  and  the  drift 
is  mainly  till.     Wells  are  usually  obtained  at  20  feet  or  less. 

.  The  city  of  Litchfield  obtains  its  public  water  supply  from  Shoal 
Creek.  A  coal  boring  at  tins  city  penetrated  75  feet  of  drift.  Wells  are 
usually  obtained  at  25  to  40  feet.  About  1^  miles  southeast  of  Litchfield 
several  deep  wells  have  been  drilled  for  oil,  a  small  quantity  of  oil  being- 
obtained  at  about  675  feet.  The  drift  at  these  wells  is  52  to  60  feet,  and 
mainly  a  hard  blue  till.    . 

On  the  plane  tracts  in  the  southeastern  part  of  the  county  wells  are 
usually  obtained  at  about  15  feet  just  above  the  blue  till.     On  neighboring 


742  THE  ILLINOIS  GLACIAL  LOBE. 

knolls  they  are  often  sunk  to  depths  of  40  feet  or  more  without  encoimter- 
ing  blue  till. 

A  well  on  a  drift  ridge  in  the  east  part  of  the  county  in  sec.  17,  T.  10, 
R.  1  W.,  reached  a  depth  of  97  feet  without  entering  rock  and  was  mainly 
through  a  hard  clay  of  yellowish  brown  color.  Beds  of  dry  sand  and  cob- 
blestone were  also  penetrated.  A  well  on  a  neighboring  section  (sec.  20) 
obtained  water  in  cobble  below  brown  till  at  a  depth  of  40  to  47  feet. 

MACOUPIN   COUNTY. 
GENERAL    STATEMENT. 

Macoupin  County  is  situated  southwest  of  the  center  of  the  State, 
imniediately  south  of  Sangamon  and  west  of  Montgomery  County.  It  has 
an  area  of  864  square  miles,  with  Carlinville  as  the  county  seat.  The 
county  is  traversed  nearly  centi'ally  from  east  to  west  by  Macoupin  Creek, 
which  is  the  only  stream  of  importance  found  within  its  limits.  The  south- 
east part  is  drained  southward  through  Silver,  Cahokia,  and  Piasa  creeks 
and  Wood  River.  The  northwest  portion  of  the  county  drains  westward 
through  Apjjle  Creek.  Narrow  strips  of  imperfectly  drained  land  occur 
along  the  divide  between  Macoupin  Creek  and  streams  flowing  southward, 
but  the  greater  portion  of  the  county  is  well  drained.  It  has  a  thin  deposit 
of  silt  somewhat  less  porous  than  typical  loess,  yet  it  absorbs  the  excess  of 
rainfall  more  rapidly  than  the  white  clay  districts  to  the  east. 

The  drift  sxirface  is  generally  plane,  though  occasional  knolls  20  to  30 
or  even  50  feet  in  height  occur.  The  largest  ones  noted  are  about  5  miles 
easi  of  Carlinville,  on  the  borders  of  Macoupin  Creek.  The  thickness 
of  the  drift  is  apparently  less  on  the  water  partings  in  the  north  and  south 
parts  of  the  county  than  near  Macoupin  Creek  in  the  central  portion.  It  is 
probable  as  noted  above  that  this  stream  follows  approximately  tlie  line  of 
a  preglacial  A'alle}'. 

'^i'he  wells  are  usually  found  at  depths  of  2.5  to  50  feet,  many  of  them 
obtaining  their  supply  above  blue  till,  but  others  in  sand  and  gravel  beneath 
it.  'I"'he  wells  and  natm-al  exposures  indicate  that  a  sheet  of  hard  blue  till 
is  generally  ])resent  in  this  county  as  in  Montgomery  County,  setting  in  at 
about  20  feet  and  extending  to  the  rock. 


WELLS  OF  MACOUPIN  COUNTY,  ILLINOIS.  743 

INDIVIDUAL    WELLS. 

At  Virdeii,  in  the  iKirth  part  of  the  county,  wells  are  usually  obtained 
at  15  to  25  feet  from  sandstone,  the  drift  being  very  thin  in  the  vicinity  of 
that  village.  The  best  wells  are  estimated  to  yield  50  barrels  per  day,  but 
usually  a  well  will  afford  only  a  small  fraction  of  that  amount.  During 
the  di'ought  of  1894-95  so  many  of  the  wells  became  dry  that  fears  of  a 
water  famine  arose. 

At  Modesto,  also  near  the  north  border  of  the  county,  rock  is  entered 
at  25  or  30  feet,  but  wells  are  usually  obtained  near  the  base  of  the  drift. 

In  the  vicinity  of  Scottville,  in  the  northwest  part  of  the  county,  the' 
drift  is  about  50  feet  in  depth  and  usually  affords  abundance  of  water  for 
wells. 

At  Girard  and  Nilwood,  in  the  northeastern  part  of  the  county,  the 
coal  shafts  enter  rock  at  about  70  feet.  Wells  are  usually  obtained  from 
thin  beds  of  sand  at  about  20  feet.     The  drift  is  mainly  a  blue  till. 

At  Carlinville  the  public  water  supply  is  pumped  from  Macoupin 
Creek.  A  coal  shaft  enters  rock  at  about  75  feet.  In  the  Geology  of 
Illinois  an  instance  of  the  penetration  of  a  thick  sheet  of  drift  near  this 
city  is  noted.  A  boring-  in  Macoupin  Creek  Valley,  made  by  T.  L.  Loomis, 
reached  a  depth  of  160  feet  without  entering  rock.  It  was  mainlv  through 
blue  till. 

At  Medora  a  coal  boring-  is  reported  in  the  Geology  of  Illinois  to  have 
the  following  section: 

Feet. 

Yellow  till 24 

Bine  till 30 

Gravel 20 

Total  drift 74 

In  the  vicinity  of  Brighton,  in  the  southwest  part  of  the  county,  rock 
is  struck  at  about  30  feet,  but  wells  are  usuall}^  found  in  the  drift. 

At  Bunker  Hill  wells  are  usually  obtained  at  20  to  30  feet  in  sand 
below  till.  They  are  estimated  to  have  an  average  daily  yield  of  about  5 
ban-els.  A  coal  shaft  in  this  village  is  reported  in  the  Geology  of  Illinois 
to  enter  rock  at  28  feet. 

At  Staunton  the  public  water  supply  is  obtained  by  impounding  water 


744  THE  ILLINOIS  GLACIAL  LOBE. 

Oil  tributaries  of  Cahokia  Creek.  Private  wells  are  obtained  usually  at 
16  to  20  feet.  Coal  shafts  penetrate  90  to  110  feet  of  drift,  mainly  blue 
till.  The  drift  is  much  thinner  northwest  from  Staunton  than  at  this 
village,  rock  Ijeing  exposed  along  Cahokia  Creek  at  a  level  only  25  feet 
below  the  bordering  uplands.  At  the  villages  of  Gillespie  and  Dorchester 
rock  is  entered  at  25  to  40  feet,  or  at  a  higher  elevation  than  the  surface 
of  the  ground  in  Staunton,  the  altitude  of  the  railway  station  at  Gillespie 
being  60  feet  and  at  Dorchester  45  feet  above  Staunton. 

GREENE  COUNTY. 
GENERAL    STATEMENT. 

Greene  County  is  situated  on  the  east  side  of  the  Illinois  River,  a  short 
distance  above  its  mouth,  and  has  an  area  of  544  square  miles,  with  Carroll- 
ton  as  the  county  seat.  It  is  drained  westward  principalh'  by  Apple  Creek 
and  Macoupin  Creek,  the  former  leading  throug'h  the  north-central  and  the 
latter  through  the  southern  portion  of  the  county.  Each  of  these  streams 
flows  in  a  trough-like  depression,  which  probably  was  the  line  of  a  pre- 
glacial  stream.  The  divides  on  either  side  of  these  depressions  rise  50  or 
75  feet  above  the  level  of  the  drift  surface  on  the  borders  of  the  creeks,  and 
they  apparently  have  a  thinner  coating  of  drift  than  the  trough- like  depres- 
sions. Wells,  however,  are  seldom  sufficiently  deep  to  test  the  thickness  of 
the  drift.  The  county  is  well  drained  by  streams  and  has  also  a  coating  of 
loess  which  absorbs  the  rainfall  rapidly. 

There  are  a  few  drift  knolls  in  the  western  half  of  the  county,  the 
largest  of  which  rise  about  50  feet  above  bordering  plane  tracts.  There 
are  not  such  well-defined  ridges  in  this  county  as  in  Pike  and  Adams  coun- 
ties, but  it  is  thought  that  these  knolls  in  Greene  County  mark  the  continu- 
ation of  the  belt  of  drift  ridges  noted  in  those  counties. 

The  drift  of  Greene  County  consists  largely  of  blue  till,  as  in  counties 
to  the  north  and  east.  The  feAv  borings  which  haxe  reached  rock  penetrate 
about  50  feet  of  drift,  and  this  is  probably  about  the  average  for  the  county. 
Preglacial  valleys  may  ])erhaps  materinlly  increase  the  average.  The  wells 
are  usually  obtainc^l  before  entering  blue  till  at  a  de])th  of  l)ut  15  or  20 
feet.  In  the  Illinois  bottoms  they  are  often  sunk  to  a  dejith  of  40  feet, 
mainly  tlirough  fine  sand. 


WELLS  OP  GREENE  COUNTY,  ILLINOIS.  745 

INDIVIDUAL    AVBLLS. 

At  Roodhouse,  in  the  north  part  of  the  county,  at  an  altitude  about  650 
feet  above  tide,  wells  obtain  water  at  15  to  25  feet  in  a  gravel  below  clay. 
A  coal  boring  is  reported  in  the  Greology  of  Illinois  to  have  penetrated  75 
feet  of  drift,  but  one  near  the  mill  entered  rock  at  35  feet  after  penetrating 
the  following  beds : 

Section  of  drift  in  a  well  at  the  Roodhouse  mill. 

Feet. 

Loess : 10 

Yellow  till 15 

Blue  till 10 

Total 35 

At  Whitehall,  4  miles  south  of  Roodhouse  and  at  75  feet  lower  eleva- 
tion, the  drift  is  shown  by  several  wells  to  have  a  thickness  of  about  50 
feet.  In  parts  of  the  village  strong  wells  are  obtained  at  20  feet,  but  in 
other  parts  they  are  sunk  to  the  rock. 

At  Carrollton  the  public  water  supply  is  from  a  well  1,330  feet  in 
depth,  which  terminates  in  the  St.  Peter  sandstone.  It  has  a  head  50  feet 
below  the  surface,  or  565  feet  above  tide.  A  peculiar  series  of  beds  were 
penetrated  before  the  rock  was  entered,  there  being  a  black  muck  about  32 
feet  in  depth  immediately  below  the  loess,  and  under  this  beds  of  yellow 
and  red  clay  extending  to  the  rock,  no  typical  till  being  found.  Rock  was 
entered  at  about  60  feet. 

At  Greenfield  the  wells  are  18  to  30  feet  in  depth  and  obtain  their 
supply  from  gravel  or  from  clay.     The  usual  depth  is  about  20  feet. 

CALHOUN    COUNTY. 
GENERAL    STATEMENT. 

Calhoun  County  occupies  the  narrow  strip  of  land  between  the  Illinois 
and  Mississippi  rivers  just  above  their  junction.  It  has  an  area  of  260  square 
miles,  and  Hardin  is  the  county  seat.  The  elevation  is  in  places  350  feet 
above  the  neighboring  streams,  and  as  the  neck  of  land  between  the  streams 
is  scarcely  6  miles  in  average  width,  the  topography  is  very  rugged  com- 
pared with  the  general  topography  of  Illinois.  Glacial  drift  is  found  only 
in  a  small  portion  of  the  county,  and  it  is  thought  by  Professor  Salisbury, 


746  THE  ILLINOIS  GLACIAL  LOBE. 

who  has  examined  the  couuty  in  sdme  detail,  that  the  greater  part  of  it  has 
never  been  glaciated.' 

The  upland  portion  of  this  county  is  sparsely  settled,  and  in  conse- 
quence iew  wells  have  been  made.  Cistern  water  furnishes  those  who  have 
not  the  money  to  sink  deep  wells.  In  the  Illinois  and  Mississippi  bottoms 
there  are  rich  farms,  and  the  wells  obtain  water  at  depths  of  30  to  60  feet 
in  the  sand  of  the  river  bottoms. 

JERSEY    COUNTY. 
GENERAL    STATEMENT. 

Jersey  County  is  situated  on  the  east  side  of  the  Illinois  River,  extend- 
mg  to  the  mouth  of  tha,t  stream  and  a  few  miles  down  the  Mississippi.  It 
has  an  area  of  360  square  miles,  with  Jerseyville  as  the  county  seat.  The 
northern  part  of  the  county  is  tributarj^  to  Macoupin  Creek.  The  central 
portion  drains  westward  through  Otter  Creek  to  the  Illinois  River.  The 
southeastern  portion  drains  southward  through  Piasa  Creek  to  the  Missis- 
sippi River.  These  streams  afford  good  drainage.  There  is  also  a  coating 
of  loess  which  absorbs  the  rainfall  rapidl}^ 

Along  the  southern  border  of  the  county  an  elevated  ridge  formed 
by  an  upheaval  of  the  rock  strata  rises  in  places  to  an  altitude  of  400 
feet  above  the  Illinois  and  Mississippi  rivers,  that  flow  along  its  base,  and 
nearly  200  feet  above  the  portion  of  the  county  to  the  north.  Aside  from 
this  ridge  the  features  of  Jersey  County  are  quite  similar  to  those  of 
Greene  County.  The  northern  portion  slopes  to  the  trough-like  depres- 
sion occupied  by  Macoupin  Creek.  A  low  ridge  having  rock  at  sHght 
depth  leads  westward  past  Jerseyville,  separating  the  drainage  basin  of 
Macoupin  Creek  from  the  basins  of  Otter  and  Piasa  creeks.  A  few  drift 
knolls  and  ridges  occur  in  the  western  and  southern  parts  of  the  county, 
the  highest  of  which  rise  perhaps  75  feet  above  bordering-  jjlains,  and 
whicli  are  a  continuation  of  the  belt  in  western  Greene  County,  noted 
above.  The  belt  of  knolls  is  traceable  nearly  to  the  Mississippi  bluffs 
south  of  Newberii,  in  the  southern  ]);irt  of  the  ccnmty. 

'i'lic  drift,  as  in  counties  to  the  north  and  east,  consists  mainly  of  till. 
Itsthi{;kness  riuiges  tVoin  20  feet  or  less  up  to  fully  100  feet.  Records  of 
eight  borings  which  reach  rock  show  an  average  of  30  feet,  but  preglacial 

'  I'roc.  Am.  Assoc.  Adv.  Sri.,  W:i«liiiiKtoM  iiici'l  ins.  ISill.  pp.  L'.">l-2riS. 


WELLS  OF  JERSEY  COUNTY,  ILLINOIS.  747 

valleys  are  liable  to  increase  the  average  much  beyond  this  amonnt.     The 
drift  is  sufficient  to  greatly  obscure  the  preglacial  valleys  and  ridges. 

Wells  are  ordinarily  but  20  or  30  feet  in  depth,  being  obtained  usually 
before  entering  the  blue  till.  On  the  bottoms  of  the  Illinois  and  Mississippi 
they  are  obtained  at  about  30  feet  in  sand  and  gravel. 

INDIVIDUAL    WELLS. 

At  Fieldon,  in  the  western  part  of  the  countv,  rock  is  strack  in  wells 
at  about  25  or  30  feet,  and  the  best  wells  are  obtained  from  this  source  at 
depths  of  40  to  60  feet. 

At  Otterville  the  wells  are  from  14  to  3-5  feet  in  depth,  and  iisually 
obtain  water  without  entering  rock.  A  section  on  Otter  Creek  bluff,  near 
this  village,  reported  in  the  Geology  of  Illinois,  is  as  follows: 

Section  of  blifff'  of  Otter  GreeJc,  near  Otterville,  Illinoifs. 

Feet. 

Yellowish  broivn  clay  (mainly  loess) 16 

Sand  and  gravel  with  bowlders 30 

Blue  clay 15 

Total   61 

The  writer  found  a  similar  section  on  a  ravine  southwest  from  Fieldon, 
and  there  the  blue  clay  at  the  base  is  a  typical  till. 

At  Beatty's  Mound,  between  Otterville  and  Jerseyville,  a  well  reached 
a  depth  of  65  feet  without  entering  rock.  The  mound  or  drift  krioll  stands 
about  40  feet  above  the  bordering  plain.  Wells  on  the  plain  north  of  the 
mound  enter  rock  at  about  30  feet. 

At  Jerse}^'ille  the  public  water  supply  is  obtained  from  a  well  2,003 
feet  in  depth,  which  obtains  most  of  its  supply  from  the  St.  Peter  sand- 
stone at  1,400  to  1,600  feet.  The  water  rises  within  100  feet  of  the  sur- 
face, or  to  562  feet  above  tide,  and  the  well  will  ^nield  by  pumping  200 
gallons  per  minute  from  a  3-inch  hole.  An  analvsis  of  the  water  is  pre- 
sented in  the  Seventeenth  Annual  Report  of  this  Survey  (Part  II,  p.  827). 
It  contains  about  86  grains  of  salt  per  gallon,  but  is  considered  a  palatable 
water.  Rock  is  entered  in  that  vicinity  at  about  20  feet,  and  wells  are 
obtained  either  near  the  base  of  the  drift  or  the  top  of  the  rock. 

At  Fidelity,  in  the  eastern  part  of  the  county,  wells  are  usually  obtained 
at  about  25  feet  near  the  base  of  the  drift,  but  a  few  pass  into  the  underlying 
rock.  In  the  eastern  and  southeastern  parts  of  the  county  the  drift  is  20  to 
35  feet  in  depth,  and  wells  not  infrequently  enter  the  rock. 


748  THE  ILLINOIS  GLACIAL  LOBE. 


MADISON    COUNTY. 
GENERAL   STATEMENT. 


Madison  County  borders  the  portion  of  the  Mississippi  River  between 
Alton  and  East  St.  Louis  and  extends  a  short  distance  northwest  of  the 
former  city.  It  has  an  area  of  740  square  miles,  with  Edwardsyille  as  the 
county  seat.  The  eastern  part  of  the  county  drains  southward  thi'ough 
Silver  Creek,  a  tributary  of  the  Kaskaskia.  The  northwestei'n  portion  is 
drained  southwestward  to  the  Mississippi  through  Cahokia  Creek  and  Wood 
River.  The  drainage  is  generally  sufficiently  well  developed  to  carry  off 
the  surplus  rainfall  rapidly,  but  there  are  small  tracts  in  the  eastern  part 
of  the  county  where  di'ainage  lines  are  not  well  developed,  and  the  white 
clay  which  covers  that  region  will  not  absorb  the  rainfall.  The  western 
half  of  the  county  is  covered  with  a  liorous  loess  which  absorbs  water 
rapidly. 

The  southeastern  part  of  the  county  is  traversed  in  a  southwestward 
course  by  a  belt  of  drift  ridges  and  knolls,  which  rise  in  places  to  a  height 
of  50  or  75  feet  above  the  bordering  plain.  A  few  knolls  occur  in  the 
northeastern  part  of  the  county,  Avhich  reach  heights  of  30  to  50  feet.  In 
the  western  part  of  the  county  the  surface  is  generally  plane,  though  a 
knoll  about  4  miles  northwest  of  Edwardsville  has  a  height  of  30  or  40  feet, 
and  knolls  10  to  15  feet  in  height  are  not  rare. 

The  drift  of  this  county,  like  that  of  Macoupin  County,  which  joins  it 
on  the  north,  consists  largely  of  a  compact  till.  This  till  has  been  noted 
along  the  bluffs  of  the  Mississippi  as  well  as  farther  east,  and  the  entire 
county  appears  to  have  been  heavily  glaciated.  Stria;  have  been  found  in 
several  places  in  and  north  of  Alton,  within  1  or  2  miles  of  the  Mississippi 
River.  The  average  thickness  of  drift  in  fifteen  borings  which  reach  the 
rock  is  found  to  be  40  feet.  As  this  does  not  include  borings  which  have 
been  made  in  ])reglacial  valleys,  the  average  for  the  county  probably  is 
somewhat  greater  than  40  feet. 

Wells  are  often  obtained  at  depths  of  20  to  25  feet  without  entering 
a  blue  till,  and  they  very  seldom  need  to  be  carried  into  tlie  rock.  Wells 
furnishing  20  barrels  per  day  ma)'  usually  be  obtained  from  the  drift,  both 
at  shallow  and  greater  depths.  Wells  are  often  sunk  below  the  first  water 
vein  in  order  to  guard  against  contamination,  for  the  porous  loess  of  the 


WELLS  OF  MADISON  COUNTY,  ILLINOIS.  749 

western    part    of  the   county   offers    a  medium  for   ready  transmission   of 
impurities. 

INDIVIDUAL    WELLS. 

At  Godfrey,  in  the  northwest  part  of  the  county,  a  deep  well  has 
recently  been  sunk  to  the  St.  Peter  sandstone  and  this  supjjlies  the  Monti- 
cello  Seminary.  Wells  at  the  railway  station  reach  a  depth  of  about  30 
feet  without  entering-  rock. 

At  Alton  the  public  water  supply  is  pumped  from  the  Mississippi  River. 
Wells  on  the  uplands  in  the  north  part  of  the  city  penetrate  30  to  40  feet 
of  drift,  and  frequently  obtain  water  without  entering  the  rock. 

At  Upper  Alton  the  wells  on  the  upland  are  usually  obtained  at  30  to 
40  feet,  near  the  base  of  the  drift.  The  loess  in  this  village  has  a  thickness 
of  20  feet  or  more,  but  is  underlain  by  typical  till,  exposures  of  which  may 
be  seen  near  Wyman  Institute.  The  village  contemplates  putting-  in  watei'- 
works,  which  will  be  supplied  from,  wells  in  the  Mississippi  Valley. 

In  the  vicinity  of  Fosterburg,  in  the  northern  part  of  the  county,  wells 
are  obtained  at  about  25  feet.  The  loess  in  that  locality  is  only  about  8 
feet  in  depth. 

At  Edwardsville  the  wells  range  in  depth  from  20  to  80  feet,  the 
shallower  ones  being  obtained  just  below  the  loess,  while  the  deeper  ones 
pass  tlrrough  a  large  amount  of  till  and  enter  rock  near  the  bottom.  This 
city  is  also  contemplating  waterworks,  but  the  source  of  supply  has  not 
been  ascertained. 

At  Collinsville  the  public  water  supply  is  from  two  wells  575  and 
600  feet  in  depth.  The  wells  are  located  on  the  Mississippi  River  bluff, 
100  feet  above  the  railway  station,  and  water  will  rise  to  a  level  120  feet 
below  the  surface.  The  wells  have  a  combined  capacity  of  not  more  than 
50,000  gallons  per  day.  The  water  is  slightly  saline,  but  can  be  drank 
by  most  people  without  discomfort.  The  supply  is  probably  either  from 
the  Coal  Measures  or  Lower  Carboniferous  sandstone.  The  drift  and 
loess  at  these  wells  is  about  90  feet  in  depth,  but  probably  not  less  than 
40  feet  is  loess.  Attention  is  here  called  to  an  error  in  the  altitude  of 
the  well  mouth  given  in  the  writer's  paper  in  the  Seventeenth  Annual 
Report  (p.  811),  the  altitude  being  565  feet  instead  of  465  feet  as  there 
given. 


750  THE  ILLINOIS  GLACIAL  LOBE. 

In  the  viciuity  of  Troy  wells  are  obtained  at  about  30  feet.  The 
loess  at  this  villag-e  is  12  or  15  feet  in  depth. 

In  the  vicinity  of  St.  Jacobs  wells  occasionally  enter  rock  at  depths  of 
40  or  50  feet  if  on  low  ground  between  the  drift  ridges.  The  drift  is  prob- 
ably much  thicker  on  the  drift  ridges,  though  no  records  of  deep  wells  were 
obtained. 

At  Highland  the  wells  on  low  ground  among  the  drift  ridges  enter 
rock  at  25  to  50  feet,  but  many  are  obtained  without  reaching  the  rock. 
North  and  east  of  Highland  wells  usually  obtain  water  at  about  20  feet 
without' entering  rock. 

At  Grrant  Fork  rock  occurs  at  a  level  only  20  feet  below  the  upland 
plain,  and  several  wells  west  of  this  village  have  been  drilled  into  the  rock 
a  few  feet.  No  data  were  obtained  concerning  the  depth  of  wells  in  the 
northeast  fourth  of  the  county. 

BOND    COUNTY. 
GENERAL    STATEMENT. 

Bond  County  is  situated  east  of  Madison,  in  the  south-central  part  of 
the  State,  and  has  an  area  of  380  square  miles,  with  Greenville  as  its  county 
seat.  The  greater  part  of  the  county  is  di-ained  southward  through  Shoal 
Creek,  a  tributary  to  Kaskaskia  River.  The  Kaskaskia  touches  the  south- 
east corner  of  the  county.  The  streams  aftbrd  rather  imperfect  di-ainage, 
and  the  white  clay  which  covers  the  glacial  drift  is  a  slow  absorbent  of  rain- 
fall. The  excess  of  rainfall  is  therefore  largely  disposed  of  by  evaporation 
except  on  the  immediate  border  of  di-ainage  lines. 

A  system  of  drift  ridges  leads  across  the  county  from  northeast  to 
southwest.  There  are  also  scattering  knolls  over  all  of  the  county. 
These  knolls  and  ridges  rise  in  some  cases  50  or  even  75  feet  above  the 
bordering  plains, 

The  thickness  of  the  drift  is  known  at  but  few  points.  Six  borings 
which  have  reached  rock  show  an  average  thickness  of  85  feet,  which  is 
probably  not  far  from  the  average  for  the  county.  The  upper  20  feet  con- 
sist of  yellow  or  ash-colored  clays,  which  in  places  assume  a  sand}'  structure 
and  supply  water  for  the  majority  of  wells.  The  deeper  portion  of  the 
drift  consists  usually  of  l)lue  till,  but  a  boring  at  Greenville  shows  a  large 
amount  of  sand  and  gravel. 


WELLS  OF  BOND  COUNTY,  ILLINOIS.  751 

INDIVIDUAL    WELLS. 

Wells  ill  the  viciuitA'  of  Soreuto,  in  the  northwest  part  of  the  county, 
often  reach  a  depth  of  30  feet  and  penetrate  the  following  beds: 

Generalized  section  of  wells  in  northwestern  Bond  County,  Illinois. 

I'eet. 

White  clay 5 

Yellow  till 12-15 

Blue  till 10-15 

Near  Old  Ripley  the  drift  is  about  50  feet  iu  depth,  but  only  a  few 
wells  reach  the  rock.     Its  structure  is  like  that  at  Sorento. 

At  Greenville  wells  are  usually  obtained  at  35  feet  in  sand  and  gravel 
below  clay.  The  public  water  supply  is  from  a  well  22  by  35  feet,  in  the 
bottom  of  which  several  tubular  wells  have  been  sunk  to  depths  of  10  or 
20  feet.  There  are  also  two  6-inch  wells  sunk  near  the  large  well,  which 
reach  a  depth  of  45  feet.  A  coal  boring  at  Greenville,  reported  in' the 
Geology  of  Illinois,  penetrated  204  feet  of  drift,  as  follows: 

Section  of  coal  boring  at  Greenville,  Illinois. 

Peet. 

Soil  anil  clay 10 

Sand  anil  clay 20 

Coarse  sand 10 

Gravel - 20 

Cemented  gravel  (possibly  till) 90 

Clay  and  saud 20 

Sand 8 

Light  clay  and  sand - 8 

Dark  clay  and  sand 18 

Total  drift 204 

A  well  in  the  valley  of  Shoal  Creek,  3  miles  above  Greenville,  is 
reported  to  have  reached  rock  at  87  feet  and  to  have  been  sunk  entirely 
through  blue  clay.  Wells  on  a  drift  ridge  in  the  city  of  Greenville  in  some 
cases  reach  a  depth  of  80  or  90  feet,  in  which  the  upper  20  feet  is  largely 
clay  and  the  remainder  sand  and  gravel. 

At  Smithboro  a  coal  boring  reported  in  the  Geology  of  Illinois  pene- 
trated 95  feet  of  drift,  as  follows : 

Section  of  coal  boring  at  Smithboro,  Illinois. 

Peet. 

Soi  1  and  clay 15 

Hardpan  (probably  till) 60 

Bine  clay 10 

Hardpan 10 

Total  drift 95 


752  THE  ILLINOIS  GLACIAL  LOBE. 

lu  the  ^^cinity  of  Wobuni  wells  on  low  drift  ridges  reach  a  depth  of 
40  feet  and  are  largelv  through  gravel.  On  the  plain  east  of  Woburn  wells 
are  usually  obtained  at  about  25  feet  and  are  mainly  tlu-ough  till. 

In  the  east  part  of  the  county,  near  Pleasant  Mound,  wells  are  usually 
obtained  at  25  or  30  feet  withou.t  entering  rock.  A  well  on  a  knoll  1^ 
miles  southeast  from  Pleasant  Mound  entered  rock  at  48  feet,  which  is  about 
the  level  of  the  base  of  the  knoll. 

FAYETTE  COUNTY. 
GENERAL   STATEMENT. 

Fayette  County  is  sitiiated  in  the  south-central  part  of  the  State,  and 
has  an  area  of  720  square  miles.  Vandalia  is  the  county  seat.  The  Kas- 
kaskia  River  leads  nearly  centrally  from  northeast  to  southwest  through  the 
county  and  has  broad  bottoms  averaging  probably  3  or  4  miles  in  width. 
No  large  tributaries  enter  within  the  limits  of  this  county.  Like  Bond 
Count)'  a  portion  of  Fayette  has  imperfect  drainage,  due  in  part  to  the  poor 
development  of  drainage  lines  and  in  part  to  the  compact  wliite  clay  which 
caps  the  sui-face. 

A  system  of  prominent  drift  ridges  is  found  in  the  southwestern  part 
of  the  county.  The  most  prominent  belt  leads  from  Vera  past  Vandalia  to 
Pleasant  Mound  in  Bond  County.  It  stands  in  some  places  100  feet  above 
the  bordering  plains  and  presents  a  complex  series  of  ridges  and  knolls 
with  an  average  breadth  of  2  miles.  The  remainder  of  the  county  has  a 
neai'ly  plane  surface. 

No  records  of  wells  have  been  obtained  by  the  writer  in  this  county 
except  at  Vandalia,  and  the  thickness  of  the  drift  is  known  at  but  few  places, 
where  outcrops  of  rock  occur.  There  is  apparently  a  filling  of  about  100 
feet  along  the  Kaskaskia  River  and  its  preglacial  tributaries,  but  on  the 
uplands  the  thickness  is  only  20  to  40  feet. 

INDIVIDUAL   WELLS. 

Wells  on  the  drift  ridges  in  the  vicinity  of  Vandalia  frequently  reach  a 
depth  of  75  feet  and  are  mainly  through  a  gravelly  drift.  The  Manual  of 
American  Waterworks  (1897)  reports  that  a  waterworks  system  is  about 
to  be  constructed  which  will  obtain  its  supply  from  the  Kaskaskia  River. 


WELLS  OP  EFFINGHAM  COUNTY,  ILLINOIS.  753 

A  boring  for  coal  made  at  this  city  reached  a  depth  of  574  feet.     It  entered 
rock  at  about  95  feet,  after  penetrating  a  complex  series  of  drift  beds. 

From  the  report  in  the  Geology  of  Illinois  (Vol.  VI)  the  following' 
information  concerning-  wells  is  obtained.  In  the  north  part  of  the  county 
the  wells  are  12  to  18  feet,  with  weak  veins  of  water.  A  well  near  Ramsey 
was  dug  100  feet  through  clay  and  gravel  to  solid  rock.  Wells  about  a 
mile  south  of  Vandalia  are  reported  to  reach  a  depth  of  60  or  65  feet  on 
the  drift  ridges  and  about  30  feet  on  the  bordering  plane  tracts.  The  wells 
usually  pass  through  a  small  amount  of  clay  at  the  top,  beneath  which  they 
are  largely  through  sand. 

EFFINGHAM    COUNTY. 
GENERAL    STATEMENT. 

Effingham  County  is  situated  in  the  south-central  part  of  the  State, 
immediately  east  of  Fayette  County,  with  Effingham  as  the  county  seat, 
and  has  an  area  of  490  square  miles.  The  greater  part  of  the  county  is 
tribixtary  to  Little  Wabash  River,  which  has  a  southward  course  through  its 
central  portion.  From  the  western  border  of  the  county  the  drainage  is 
westward  to  the  Kaskaskia.  The  divides  in  this  county  are  poorly  drained 
as  in  neighboring  counties,  and  there  is  a  coating  of  white  clay  over  the 
entire  upland  surface  which  absorbs  water  very  slowly. 

The  drift  surface  is  generally  plane,  there  being  no  prominent  ndges 
or  knolls,  such  as  occur  in  the  neighboring  counties  on  the  north  and  west. 
Rock  is  exposed  along  the  Little  Wabash  and  its  tributaries  and  also  along 
tributaries  of  the  Kaskaskia  at  levels  only  20  to  40  feet  below  the  border- 
ing uplands.  The  tliickest  section  of  drift  obtained  within  the  county  is 
only  60  feet.  The  upper  part  of  the  drift  to  a  depth  of  25  feet  or  more  is 
composed  of  clays  of  yellow  or  brown  color  which  usually  afford  water  for 
the  wells.  Under  these  clays  is  a  hard  blue  till  extending  frequently  to 
the  rock. 

INDIVIDUAL    WELLS. 

At  Altamont  a  well  at  the  Boyer  House  penetrated  about  15  feet  of 
white  and  yellow  clays  with  few  pebbles,  beneath  which  a  hard  brown  till 
was  entered,  and  below  that,  at  a  depth  of  a  few  feet,  a  blue  till.  The  well 
terminated  in  this  blue  till  at  a  depth  of  47  feet.  Other  wells  in  the  village 
obtain  water  without  entering  the  blue  till.  Within  a  few  miles  southwest 
MON  xxxviii 48 


754  THE  ILLINOIS  GLACIAL  LOBE. 

of  Altamont,  on  the  divide  between  the  Little  Wabash  and  Kaskaskia,  wells 
enter  rock  at  about  30  feet  and  obtain  water  at  40  or  50  feet. 

In  the  vicinity  of  Moccasin  and  Beecher  wells  occasionally  enter  rock 
at  30  to  40  feet,  but  are  usually  obtained  at  20  or  30  feet  from  drift  beds 
of  sandy  structure. 

In  the  vicinity  of  Effingham  wells  are  obtained  at  18  to  20  feet  in 
sandy  beds  below  till.  Rock  is  entered  at  25  or  30  feet.  The  supply  for 
waterworks  is  pumped  from  Little  Wabash  River. 

In  the  vicinity  of  Edgewood  and  Mason,  in  the  southern  part  of  the 
county,  rock  is  usually  entered  at  20  to  25  feet,  but  most  of  the  wells  obtain 
their  supply  from  near  the  base  of  the  drift.  A  coal  boring  near  Edge- 
wood  is  reported,  in  the  Geology  of  Illinois,  to  have  penetrated  59  feet  of 
drift. 

JASPER  COUNTY. 

GENERAL    STATEMENT. 

Jasper  County  is  situated  east  of  Effingham,  with  Newton  as  the  countv 
seat,  and  has  an  area  of  506  square  miles.  The  Embarras  River  runs  south- 
eastward through  the  central  portion  of  the  county.  Its  tributaries  are 
mainly  on  the  northeast,  leaving  the  western  and  southern  portions  of  the 
county  outside  its  drainage  basin  and  tributary  to  the  Little  Wabash.  TJie 
valley  of  the  Embarras  is  neai-ly  2  miles  in  average  width  and  has  sandy 
bottoms.  The  uplands  in  this  county,  as  in  tlie  neighboring  counties  on  the 
north  and  west,  are  covei'ed  with  a  white  clay,  which  absorbs  rainfall  very 
slowly. 

The  drift,  like  that  of  Effingham  County,  is  composed  mainly  of  till 
of  moderate  depth,  seldom  more  than  50  feet.  Along  the  Embarras  River, 
however,  the  depth  is  greater  and  may  exceed  100  feet.  Tributaries  of  the 
preglacial  Embarras  have  been  filled  so  completely  that  their  courses  can 
scarcely  be  traced.  The  wells  are  usually  obtained  at  depths  of  only  20  or 
30  feet.  But  few  records  have  been  procured,  the  conditions  for  wells  being 
somewhat  uniform  throughout  the  county. 

INDIVIDUAL    WELLS. 

In  the  vicinity  of  Newton  wells  are  usually  about  20  feet  deep,  and  in 
a  few  instances  they  reach  rock  at  that  depth.  The  waterworks  suppl}'  is 
])nini)(ul  from  the  Embarras  River. 


WELLS  OF  CRAWFORD  COUNTY,  ILLINOIS.  7o5 

At  St.  Marie  a  well  at  Mr.  Picquet's  did  uot  enter  rock  at  a  depth  of  30 
feet,  but  other  wells  iu  the  village  strike  rock  at  only  16  feet.  West  from 
St.  Marie,  along  the  divide  between  Embarras  and  Little  Wabash  rivers, 
wells  are  about  20  feet  in  depth  and  do  not  enter  rock. 

Wells  along  the  Embarras  River  in  the  southeast  part  of  the  county 
are  30  to  45  feet  in  depth  without  entering  rock.  After  penetrating  a  few 
feet  of  sand  they  are  lai-gely  tlu-ough  blue  till. 

CRAWFORD    COUNTY. 

GENERAL    STATEMENT. 

Crawford  County  is  situated  on  the  eastern  border  of  the  State  imme- 
diately south  of  Clark  County  and  east  of  Jasper.  It  has  an  area  of  462 
square  miles,  with  Robinson  as  the  county  seat.  The  eastern  border  is  fol- 
lowed by  the  Wabash  River,  which  receives  the  di-ainage  of  a  narrow  strip 
along  its  west  bluff.  The  western  half  of  the  county  is  tributary  to  the 
Embarras  River,  but  that  stream  touches  only  the  extreme  southwest  corner 
of  the  county.  This  county,  like  those  on  the  north  and  west,  is  covered 
with  white  clay  which  absorbs  rainfall  slowly,  although  not  so  impervious 
to  water  as  the  white  clay  in  the  south-central  part  of  the  State. 

The  drift  is  apparently  of  slight  depth  on  the  uplands,  rock  being 
entered  in  wells  at  many  points  within  10  or  15  feet  of  the  surface.  There 
may,  however,  be  deeply  filled  preglacial  valleys  tributary  to  the  Wabash 
and  Emban-as,  whose  courses  are  concealed  by  the  drift.  Where  wells  do 
not  enter  rock  they  usually  obtain  water  at  a  depth  of  20  feet  or  less,  and 
thus  do  not  test  the  tliickness  of  the  drift  in  its  deeper  portions.  Wells 
which  enter  rock  obtain  water  without  penetrating  to  great  depth,  there 
being  few  wells  more  than  100  feet  in  depth. 

INDIVIDUAL   WELLS. 

In  the  northern  part  of  the  county  wells  are  usually  obtained  in  sind- 
stone  at  a  depth  of  35  feet  or  less.  The  drift  is  often  not  more  than  15  feet 
in  depth. 

In  the  vicinity  of  Trimble  the  rock  is  in  places  scarcely  10  feet  below 
the  surface  and  wells  are  obtained  at  moderate  depths  in  sandstone. 

At  Robinson  wells  are  20  to  25  feet  in  depth  and  usually  enter  sand- 
stone a  few  feet.  The  mayor,  Mr.  Aldridge  Walters,  estimates  that  good 
wells  will  yield  40  or  50  barrels  per  day. 


756  THE  ILLINOIS  GLACIAL  LOBE. 

In  the  vicinity  of  Duncanville  wells  are  obtained  in  sand  below  clay 
at  a  depth  of  18  (ir  20  feet.  On  the  higher  parts  of  the  upland  rock  is 
entered  at  10  or  15  feet.  In  the  vicinity  of  Flat  Rock,  also,  the  drift  is  but 
10  or  15  feet  in  depth. 

In  the  west  part  of  the  county,  in  the  vicinity  of  Oblong,  wells  art- 
usually  obtained  at  about  16  feet  without  entering  rock. 

LAWRENCE    COUNTY. 
GENERAL    STATEMENT. 

Lawrence  County  is  situated  south  of  Crawford,  on  the  east  border  of 
the  State,  and  has  an  area  of  360  square  miles,  with  Lawrenceville  as  the 
county  seat.  The  Wabash  River  forms  the  eastern  border  of  the  county 
and  Embarras  River  traverses  it  nearly  ceiiti'ally.  Both  streams  have 
broad  sandy  bottoms  several  miles  in  width.  The  lowlands  connected 
with  these  bottoms  are  poorly  drained,  but  uplands  are  hilly  and  well 
drained.  The  liigher  portions  of  the  county  have  a  capping  of  white  clay, 
but  the  lowlands  and  river  bottoms  are  usually  covered  with  sand. 

The  drift  on  the  uplands  is  very  thin,  rock  usually  being  found  within 
10  or  15  feet  of  the  surface.  Wells  are,  however,  obtained  at  moderate 
depths,  there  being  few  which  have  failed  to  obtain  water  within  50  feet  of 
the  surface.  On  the  lowlands  the  drift  is  probably  thick,  though  wells  are 
obtained  without  reaching  the  underlying  rock.  A  well  across  the  Wabash, 
at  Vincennes,  Indiana,  reached  a  level  about  60  feet  below  the  river  before 


entering  rock. 


INDIVIDUAL    WELLS. 


At  Lawrenceville  the  best  wells  are  obtained  from  sandstone  at  a  depth 
of  about  60  feet.     Rock  is  entered  at  only  10  to  15  feet. 

In  the  vicinity  of  Sumner  strong  wells  are  obtained  at  about  20  feet 
from  sand  and  gravel  below  clay. 

At  St.  Francisville  the  wells  average  only  15  feet  in  depth,  mainly 
througli  sand. 


RICHLAND  COUNTY. 

GENERAL    S'I'ATEMENT. 


Richland  County  is  situated  inunediately  west  of  Lawrence,  with  Olney 
as  the  county  seat,  and  has  an  area  of  361  square  miles.  The  eastern  por- 
tion  of  tlic   county-   (lr;iins   southward    to   IVmpas   River   and   the  western 


WELLS  OF  CLAY  COUNTY,  ILLINOIS.  757 

tliroug-h  Fox  River,  a  tributary  to  the  Little  Wabash.  This  county,  like 
those  to  the  north  and  west,  has  a  coating  of  white  clay  which  is  very  slowly 
pervious  to  water.  The  excess  of  rainfall  escapes  largel)^  through  evapora- 
tion. Along  the  streams  and  in  lowlands  there  is  usually  a  black  mucky 
soil,  much  richer  than  the  white  clay  of  the  uplands  and  more  readily  per- 
vious to  water. 

On  the  uplands  the  drift  is  generally  very  thin,  the  rock  often  being 
entered  at  only  10  or  15  feet.  On  the  lowlands  the  thickness  is  much 
greater,  and  wells  are  obtained  at  20  feet  or  less  without  entering  the  rock. 

INDIVIDUAL    WELLS. 

At  the  city  of  Olney  private  wells  usually  obtain  water  at  a  depth  of 
10  or  12  feet  from  a  gi-avelly  bed  resting  on  the  rock.  The  waterworks 
supply,  which  is  chiefly  for  fire  protection  and  lawns,  is  pumped  from  Fox 
River.  A  boring  2,000  feet  in  depth  was  made  at  this  city  for  the  purpose 
of  obtaining  an  artesian  well.  A  salt  water  was  sti'uck  which  does  not  over- 
flow, and  no  use  is  made  of  the  well.  South  of  Olney,  near  Parkersburg, 
a  well  is  reported  to  have  struck  wood  in  clay  at  20  feet. 

In  the  north  part  of  the  county,  near  Dundas,  rock  is  usually  entered 
at  12  to  18  feet,  though  wells  are  sometimes  of  less  depth. 

CLAY    COUNTY. 
GENERAL    STATEMENT. 

Clay  County  is  situated  west  of  Richland  and  south  of  Effingham 
County.  It  has  an  area  of  470  square  miles,  with  Louisville  as  the  county 
seat.  The  county  is  traversed  by  the  Little  Wabash  River  neai'ly  centrally 
in  a  northwest  to  southeast  course.  The  greater  portion  is  directly  tributary 
to  this  stream,  but  a  nari'ow  strip  on  the  western  border  is  tributarv  to 
Skillett  Fork,  a  stream  which  enters  the  Little  Wabash  near  its  mouth.  This 
county,  like  the  neighboring  counties  just  discussed,  has  a  coating  of  wliite 
clay  several  feet  in  depth,  wliich  is  very  slowly  pervious  to  water.  The 
streams,  however,  are  bordered  by  broad  bottoms  with  looser  and  more 
fertile  soil. 

The  drift  on  the  uplands  is  usually^  but  15  to  30  feet  in  depth.  Wells 
are  in  many  cases  obtained  in  the  di'ift,  but  a  large  number  penetrate  the 
imderlying  rock  a  few  feet.     The  drift  along  the  streams  is  probably  of 


758  THE  ILLINOIS  GLACIAL  LOBE. 

greater  depth  than  on  the  uplands,  but  no  well  records  have  been  obtained 
to  demonstrate  this  greater  thickness. 

INDIVIDUAL   WELLS. 

In  the  vicinit}^  of  lola,  in  the  northwest  part  of  the  county,  wells 
obtain  water  at  12  to  15  feet  without  entering  rock.  They  are  mainly 
through  a  yellow  clay. 

At  Louisville  rock  is  entered  at  about  27  feet,  but  wells  frequenth' 
obtain  water  in  the  lower  part  of  the  drift.  An  exposiire  on  the  bluff  of 
Little  Wabash  River  in  this  village  shows  the  following  beds: 

Section  of  bluff  of  Little  Wabash  River  near  Louisville,  Illinois. 

Feet. 

Brown  silt  with  few  pebbles 6 

Brown  sandy  gravel 5 

Brown  leached  till 4 

Gray  calcareous  till 12 

Coal  Measures  shale 10 

Total  drift 27 

On  the  uplands  west  and  south  from  Louisville  rock  is  usually  entered 
at  15  to  20  feet,  though  at  elevations  a  few  feet  higher  than  the  site  of  the 
village. 

At  Flora  rock  is  usually  strack  at  15  or  20  feet  and  wells  are  obtained 
at  30  to  50  feet. 

In  the  vicinity  of  Xenia  rock  is  entered  at  about  15  feet  and  wells 
obtain  Avater  at  slight  depth  in  the  underlying  sandstone  or  sandy  shale. 

MARION   COUNTY. 
GENERAL   STATEMENT. 

Marion  County  is  situated  west  of  Clay  County  and  south  of  Fayette, 
about  midway  between  the  Wabash  and  Mississippi  rivers.  It  has  an  area 
of  580  square  miles,  with  Salem  as  the  county  seat.  The  divide  between 
the  Mississippi  and  Wabash  rivers  passes  tlu'ough  the  eastern  part  of  the 
county.  The  greater  part  of  the  count}^  drains  westward  through  small 
creeks  into  the  Kaskaskia.  The  eastern  part  drains  southward  through 
Skillett  Fork,  a  tributar)-  of  Little  Wabash  River.  The  streams  afford 
imperfect  drainage,  and  the  sheet  of  white  clay  that  covers  the  county 
absorbs  rainfall  very  slowly.  The  excess  of  rainfall  is  therefore  disposed 
of  by  evaporation. 


WELLS  OF  MARION  COUNTY,  ILLINOIS.  759 

Throughout  much  of  the  county  rock  is  entered  in  wells  and  coal 
shafts  at  depths  of  only  20  or  30  feet,  but  borings  at  Salem,  Odin,  and 
Sandoval  penetrate  over  100  feet  of  drift,  apparently  striking  the  line  of  a 
preglacial  valley.  Where  the  drift  exceeds  20  feet  in  depth  its  lower  por- 
tion is  usually  a  blue  till,  but  where  less  than  20  feet  the  till  is  of  a  yellow 
or  brown  color.  Wells  are  usually  obtained  at  only  15  to  30  feet,  and  the 
majority  do  not  enter  rock. 

INDIVIDUAL   WELLS. 

At  Patoka,  in  the  northwest  part  of  the  county,  a  well  at  the  railway 
station  is  reported  in  the  Geology  of  Illmois  to  have  struck  rock  at  a  depth 
of  60  feet.     It  penetrated  the  following  beds: 

Section  of  well  at  Patoka.,  Illinois. 

Feet. 

Soil,  clay,  etc 15 

Hardpan 15 

Blue  pebbly  clay  vrith  fragmentB  of  coal  and  wood 30 

Fossiliferons  limestone 2 

Soft  shale 30 

'I'otal  depth 92 

The  wells  in  that  vicinity  ordinarily  obtain  water  without  entering  rock. 

At  Kinmundy,  in  the  north  part  of  the  county,  rock  is  entered  at  12  to 
20  feet,  and  wells  often  penetrate  it  a  few  feet  to  obtain  water. 

At  Salem  wells  are  usually  obtained  at  about  20  feet  from  sandy  beds 
in  the  drift.  A  coal  boring  reported  in  the  Geology  of  Illinois  penetrated 
126  feet  of  drift,  as  follows : 

Section  of  coal  boring  at  Salem,  Illinois. 

Feet. 

Soil 2 

Ferruginous  crust  of  clay ■ 3 

Yellow  till 9 

Yellow  till  and  sand 10 

Blue  till 50 

Brown  clay,  containing  wood 30 

Blue  clay,  sand,  and  wood 12 

Black  soil 1 

Blue  mud  and  sand - 9 

Total  drift 126 

At  Odin  a  coal  boring  penetrated  100  feet  of  drift,  and  at  Sandoval 
128  feet.  Wells  at  Sandoval  obtain  water  at  14  to  18  feet  from  a  sandy 
clay.     A  good  well  is  estimated  to  yield  35  barrels  a  day. 


760  THE  ILLINOIS  GLACIAL  LOBE. 

At  Centralia  wells  obtain  water  at  14  to  30  feet  from  clay  or  gravel. 
The  public  supply  is  from  impounded  water. 

CLINTON   COUNTY. 
GENERAL,   STATEMENT. 

Clinton  County  is  situated  west  of  Marion  County,  in  the  southwestern 
part  of  the  State,  with  Carlyle  as  the  county  seat,  and  has  an  area  of  494 
square  miles.  The  Kaskaskia  River  leads  southward  through  the  eastern 
part  of  the  county  and  there  turns  westward,  forming  the  south  boundary. 
Shoal  Creek,  its  largest  ti'ibutary,  traverses  the  west-central  part  of  the 
county  and  enters  the  Kaskaskia  about  8  miles  from  the  west  border  of  the 
county.  Crooked  Creek,  an  eastern  tributary,  forms  a  part  of  the  south 
boundary  of  the  county.  The  streams  have  channels  sunk  but  a  few  feet 
below  the  level  of  the  bordering  plains  and  drainage  lines  are  not  well 
developed.  The  compact  white  clay  which  covers  the  county  absorbs  the 
rainfall  slowly,  thus  leaving  much  of  it  to  be  disposed  of  by  evaporation. 

Occasional  drift  ridges  and  knolls  break  the  monotony  of  the  plain. 
The  highest  reach  elevations  of  50  to  75  feet  or  more  above  the  plain,  and 
the  majority  have  a  height  of  fully  30  feet.  The  best  developed  system  of 
ridges  appears  along  the  Kaskaskia  River,  east  and  southeast  of  Carlvle. 
There  is  a  nearly  continuous  chain  of  knolls  about  5  miles  in  length,  which 
crosses  the  Baltimore  and  Ohio  Railway  in  north  to  south  direction  ab(iut 
3  miles  east  of  Carlyle.  These  knolls  and  ridges  connect  on  the  north 
with  those  in  Bond  and  Fayette  counties  already  discussed. 

The  thickness  of  the  di'ift  in  this  county  seldom  exceeds  50  feet,  and 
not  a  few  wells  enter  rock  at  15  to  30  feet.  A  few  drift  sections  are  reported 
in  the  Geology  of  Illinois  which  penetrate  70  feet  of  drift.  In  its  thicker 
portions  the  di-ift  includes  a  hard  blue  till  near  its  base,  but  it  usualh'  has  a 
yellow  color  to  a  depth  of  at  least  20  feet.  The  wells  are  obtained  either 
in  the  sandy  portions  of  the  yellow  till  or  at  slight  depth  in  th6  underlying 
rock.  The  blue  till  is  apparently  very  compact  and  a  poor  medium  for 
su])plying  water. 

INDIVIDUAL    WELLS. 

At  Carlyle  wells  are  usually  obtained  at  about  25  feet  without  entering 
rock.     The  waterworks  are  supplied  from  the  Kaskaskia  River. 


WELLS  OF  CLINTON  COUNTY,  ILLINOIS. 


761 


A  well  on  one  of  the  di-ift  knolls  southeast  from  Carlyle  in  sec.  14, 
T.  1  N.,  R.  2  W.,  was  mainly  through  sand  and  gravel  to  a  depth  of  46  feet. 
It  is  thought  by  the  residents  that  most  of  these  knolls  and  ridges  contain 
much  sand  and  gravel. 

The  following  table  of  well  borings  is  compiled  from  data  furnished 
in  the  Geology  of  Illinois  (Vol.  Ill): 

WelLi  in  Clinton  County. 


Owner  or  location. 

Altitude 
(above 
tide). 

Depth. 

Remarks. 

Sec.  5,  T.  3,  R.  2  W              .     .  . 

Feet. 
500 
500 
475 
475 
475 
450 
490 

Feet. 
40 
36 
50 
70 
70 
52 
27 

Sec.  6,  T.  3,  R.  2  W 

Beaver  Prairie,  T.  3,  R.  3  W. . . . 

Drift  knolls,  T.  1,  R.  3  W 

Sec.  34,  T.  2,  R.  4  W 

No  rock ;  several  wells. 

Several  wells ;  drift  about  70  feet. 

On  knoll,  mainly  saml. 

ST.    CLAIR    COUNTY. 


GENERAL    STATEMENT. 


St.  Clair  County  is  situated  in  the  .southwestern  jjart  of  the  State  and 
borders  the  Mississippi  River  for  a  few  miles  opposite  the  city  of  St.  Louis. 
It  has  an  area  of  680  square  miles,  with  Belleville  as  the  county  seat.  The 
Kaskaskia  River  crosses  its  southeastern  corner,  and  the  greater  part  of  the 
county  is  tributary  to  that  river  tlii-ough  Silver  and  Richland  creeks,  there 
being  only  a  narrow  strip  along  the  bottoms  and  east  bluff  of  the  Missis- 
sippi which  is  not  tributary  to  it.  This  strip  along  the  Mississippi  bluffs  is 
largely  underlain  by  St.  Louis  limestone,  in  which  subterranean  drainage  is 
developed  through  caverns  and  sink  holes.  The  western  portion  of  the 
county  is  covered  with  a  deposit  of  porous  loess,  which  extends  as  far  east 
as  the  meridian  of  Belleville.  The  eastern  portion  is  largely  covered  by  a 
white  clay,  though  scarcely  so  compact  as  that  found  in  counties  to  the  east. 

A  belt  of  prominent  drift  ridges  leads  southward  through  the  eastern 
half  of  the  county,  passing  between  Lebanon  and  O'Fallon,  and  just  east 
of  the  city  of  Belleville.     These  ridges  rise  in  places  to  a  height  of  fully 


762  THE  ILLINOIS  GLACIAL  LOBE. 

100  feet  above  tlie  bordering- plain,  and  are  a  foutinuation  of  the  belt  which 
crosses  southeastern  Madison  County,  noted  above.  East  of  this  belt  there 
are  a  few  isolated  knolls  or  groups  of  knolls  which  stand  30  to  50  feet  or 
more  above  the  border  plains. 

In  the  elevated  limestone  district  on  the  west  border  of  the  county 
there  is  but  little  glacial  drift  beneath  the  loess,  but  eastward  from  the  belt 
of  drift  ridges  just  noted  the  county  is  coated  so  heavily  that  wells  seldom 
reach  the  rock.  The  extreme  southeast  part  of  the  county,  however,  has  a 
thin  coating  of  drift,  and  wells  often  enter  the  rock.  The  drift  ridges  are 
composed  in  part  of  till  and  in  part  of  sand  and  gravel.  A  blue  till  is 
found  near  the  base,  but  the  upper  30  or  40  feet  is  usually  of  brown  or 
yellow  color. 

INDIVIDUAL   WELLS. 

At  East  tSt.  Louis,  in  the  extreme  northwest  comer  of  the  county,  on 
the  low  bottom  of  the  Mississippi  River,  borings  and  bridge  foundations 
have  penetrated  120  to  140  feet  of  fine  sand,  reaching  a  level  about  100 
feet  below  the  low- water  mark  of  the  river  before  entering  rock.  Private 
wells  are  obtained  at  a  depth  of  about  35  feet.  The  public  water  supply 
is  pumped  from  the  Mississippi  River. 

At  East  Carondelet,  also  in  the  Mississippi  bottoms,  about  6  miles 
below  East  St.  Louis,  wells  are  usually  obtained  at  a  depth  of  about  40 
feet,  but  Mr.  H.  L.  Pugh  has  driven  several  wells  to  a  depth  of  60  feet. 
The  upper  40  feet  is  a  fine  sand,  but  the  lower  20  feet  is  a  fine  gravel  or 
coarse  sand.  Piles  driven  at  the  foundation  of  the  Meier  Iron  Works  are 
thought  to  have  struck  solid  rock  at  a  depth  of  90  feet,  or  a  level  nearly 
60  feet  below  the  low-water  mark  of  the  river. 

On  the  Mississippi  bluff"  in  the  northwest  part  of  the  county  the  loess 
ranges  in  thickness  from  20  to  about  50  feet,  and  the  few  wells  which  are 
made  in  that  region  are  usually  sunk  some  distance  into  the  underlying 
rock.     The  residents  usually  depend  upon  cistern  water. 

At  Millstadt  the  best  wells  are  obtained  in  rock  at  a  depth  of  25  to  40 
feet.  A  test  boring  made  at  this  village  reached  a  depth  of  620  feet.  The 
water  has  a  head  75  feet  below  the  surface  and  there  is  only  a  small  amount, 
estimated  at  about  4  gallons  per  minute. 


WELLS  OF  ST.  GLAIE  COUNTY,  ILLINOIS.  763 

At  Belleville  the  waterworks  is  supplied  in  part  from  a  well  diilled  in 
the  valley  of  Richland  Creek  and  in  part  by  impounded  water  from  Rich- 
land Creek  and  a  tributary.  The  well  entered  rock  at  a  depth  of  42  feet 
after  penetrating  the  following  series  of  drift  beds : 

Section  of  well  at  Belleville,  Illinois. 

Feet. 

Yellow  till 25 

Black  muck,  resembling  soil 2 

Yellow  clay 6 

Blue  clay 9 

Total  drift 42 

Several  prospect  borings  for  the  waterworks  have  been  made  along 
Richland  Creek  Valley,  between  Belleville  and  O'Fallon,  wliich  penetrate  in 
some  instances  80  feet  of  drift,  mainlj^  till.  The  amount  of  water  is  scarcely 
sufficient  to  fm'nish  a  supply  for  water  works,  hence  the  use  of  impounded 
water  is  continued.  A  M^ell  at  the  Star  Bi'ewery,  in  the  northern  part 
of  Belleville,  reached  a  depth  of  503  feet  and  obtained  a  slightly  saline 
water,  with  head  80  feet  below  the  surface.  The  depth  of  the  drift  is 
87  feet.  Coal  shafts  near  the  Louisville  and  Nashville  depot,  in  the  north- 
ern part  of  Belleville,  penetrate  mainly  blue  till  and  enter  rock  at  depths  of 
40  to  80  feet,  the  rock  surface  being  somewhat  uneven.  A  coal  shaft  just 
south  of  Belleville  enters  rock  at  30  feet,  and  there  are  exposures  of  rock 
within  the  city  limits. 

At  the  village  of  Lebanon,  in  the  northeast  part  of  the  county,  shallow 
wells  obtain  water  from  gravel  below  clay  at  a  depth  of  30  or  40  feet. 
Considerable  wood  is  found  in  some  of  the  wells.  There  are  also  several 
deep  wells  in  the  village  obtaining  water  from  limestone  at  150  to  200  feet. 
On  a  drift  ridge  2  miles  north  of  the  village  a  well  made  by  D.  Bitzer 
reached  a  depth  of  86  feet  without  encountering  rock.  The  lower  46  feet 
was  a  hai-d  blue  till  containing  fragments  of  wood.  The  upper  40  feet  con- 
sisted of  alternations  of  clay  with  gravel.  The  altitude  at  this  well  is  fully 
60  feet  above  the  railway  station  at  Lebanon. 

At  Summerfield  rock  is  entered  at  about  35  feet,  but  on  the  plain  north 
of  this  village  the  wells  usually  penetrate  50  feet  of  drift  before  entering 
rock. 


764  THE  ILLINOIS  GLACIAL  LOBE. 

A  coal  shaft  at  Mascoutah  is  reported  in  tlie  Geology  of  Illinois  to 
penetrate  the  following  beds  of  drift: 

Section  of  coal  shaft  at  Mascoutah^  Illinois. 

Feef. 

Soil  and  day -0 

Sand fl 

Blue,  gray,  and  red  clay 50 

Coarse  eand  with  wood 6 

Total  drift 82 

At  Rentchler  wells  enter  rock  at  about  40  feet,  but  on  the  drift  ridges 
between  that  place  and  Wilderman  two  wells  are  reported  to  have  reached 
a  depth  of  85  feet  without  entering'  rock. 

The  following  section  of  thick  drift  is  reported  in  the  Geology  of 
Illinois.     The  boring  was  made  in  sec.  20,  T.  1  S.,  R.  6  W. : 

Section  of  a  horinrjin  sec.  30,  T.  1  S.,  R.  6  W. 

Feet. 

Soil  and  yellow  clay 14 

Eeddish  brown  gravel  and  sand 28 

Blue  clay 83 

Total  drift 125 

111  the  vicinity  of  Freeburg  and  Smithtou  rock  is  entered  in  the  deeper 
wells  at  about  25  to  30  feet.  The  upper  5  or  10  feet  is  a  loess  or  pebble- 
less  silt,  and  the  remainder  is  a  brown  clay  containing  few  pebbles.  There 
appears  to  be  but  little  typical  till  in  this  locality  or,  for  that  matter,  in  any 
part  of  the  county  west  and  south  from  Belleville. 

At  Lementon  a  coal  boring  reported  in  the  Geology  of  Illinois  has  the 
following  section  of  drift: 

Section  of  drift  beds  in  a  coal  borinf/  at  Lementon,  Illinois. 

Feet. 

Soil 3 

Yellow  clay 14 

Sand  and  gravel 1 

Blue  clay 20 

Clay  resembling  soil 1 

Blue  and  yellow  clay 11 

Red  and  yellow  sand 1 

Total  ilrilt 51 

On  a  di'ift  ridge  southwest  of  Lementon  a  well  made  by  Mr.  L.  Her- 
mann reached  a  dejith  of  65  feet  without  entering  rock.  The  upper  23  feet 
was  mainly  till;   the  remainder  sand  and  gravel. 


WELLS  OF  MONEOE  COUNTY,  ILLINOIS.  765 

Near  New  Athens  coal  shafts  and  borings  enter  rock  at  depths  ranging 
from  37  to  75  feet.  A  well  at  J.  Hardy's,  south  of  New  Athens,  reached  a 
depth  of  90  feet  without  entering  rock,  and  several  wells  in  that  vicinity 
are  50  feet  in  depth.  Southeast  from  New  Athens  rock  is  usually  entered 
within  30  feet  of  the  surface.  Some  of  the  highest  points  have  rock  at 
surface. 

MONROE   COUNTY. 
GENERAL    STATEMENT. 

Monroe  County  borders  the  Mississippi  River  below  St.  Clair  County, 
and  has  an  area  of  380  square  miles,  with  Waterloo  as  the  county  seat.  The 
western  part  of  the  county  is  largely  occupied  by  the  St.  Louis  limestone,  and 
is  characterized  by  subterranean  drainage  through  sink  holes  and  caverns. 
The  limestone  is  covered  with  a  deposit  of  loess,  but  there  is  very  little  gla- 
cial drift.  In  the  northern  end  of  the  county,  near  Columbia,  there  is  a 
lowland  occupied  by  Coal  Measures,  in  which  di-ift  40  feet  or  more  in  depth 
has  been  deposited.  The  eastern  part  of  the  county  is  occupied  by  Coal 
Measures  and  its  drainage  is  tributary  to  the  Kaskaskia,  that  stream  being 
the  eastern  border  of  the  county. 

The  belt  of  drift  ridges  which  have  been  traced  southward  tln-ough  St. 
Clair  County  cross  the  eastern  border  of  Monroe  County,  following  nearly 
the  west  bluff  of  the  Kaskaskia  River.  The  drift  on  this  ridg-ed  belt  has 
been  penetrated  in  one  instance  115  feet  and  in  several  instances  60  to  75 
feet  without  reaching  the  rock.  It  is  found  to  be  partly  sand  and  partly  till. 
West  from  this  ridged  belt  the  drift  is  thin,  seldom  exceeding  20  feet.  Wells 
are  usually  obtained  from  the  rock,  except  along  the  belt  of  ridged  drift  and 
in  the  Mississippi  bottoms.  Strong  wells  are  seldom  obtained  in  the  rock 
at  less  than  50  feet,  and  not  infrequently  they  are  80  feet  in  depth.  The 
wells  in  the  Mississippi  Valley  are  only  40  or  50  feet  in  depth,  and  are 
largely  through  fine  sand.  The  wells  along  the  belt  of  ridged  drift  vary 
greatly  in  depth,  some  being  obtained  at  about  30  feet,  while  others  are  sunk 
to  twice  or  thi'ice  that  depth. 

INDIVinUAL    WELLS. 

At  Columbia  the  wells  are  20  to  45  feet  in  depth,  the  deeper  ones  being 
from  the  rock.  A  prospect  boring  for  artesian  water  was  sunk  to  a  depth 
of  1,010  feet.     It  has  a  head  10  or  15  feet  below  the  surface.     No  use  is 


766  THE  ILLINOIS  GLACIAL  LOBE. 

made  of  the  well  at  present.  Exposures  iu  the  ravines  near  Columbia  show 
a  deposit  of  loess  about  12  feet  in  depth,  beneath  which  there  are  yellow 
and  blue  clays  containing  a  few  pebbles  and  an  occasional  bowlder  as  well 
as  numerous  fragments  of  wood.  The  rock  fragments  are  far  less  numerous 
than  in  typical  till. 

At  Waterloo  the  wells  range  in  depth  from  20  to  80  feet,  and  nearly 
all  are  from  limestone.  One  at  the  mill,  however,  20  feet  in  depth,  was 
obtained  without  entering  rock.  A  well  at  the  electric  light  plant  is  reported 
to  have  entered  rock  at  about  30  feet.  The  Manual  of  American  Water- 
works (1897)  reports  that  an  impounding  reservoir  has  been  constnicted 
with  a  view  to  obtaining  a  public  water  supply. 

In  the  vicinity  of  Burksville  wells  occasionally  reach  a  depth  of  30  or 
40  feet  before  entering  rock.  They  are  mainly  through  a  nearly  pebbleless 
clay,  yellow  at  top  and  blue  in  its  deeper  portion. 

In  the  vicinity  of  Glasgow  (Renault  post-office)  wells  are  often  sunk  to 
a  depth  of  50  feet.  The  distance  to  rock  ranges  from  10  feet  to  fully  50 
feet,  but  a  large  amount  of  the  clay  above  the  rock  is  apparently  residuary, 
there  being  very  little  g'lacial  drift  in  this  locality.  The  clay  has  the  deep 
reddish  brown  color  characteristic  of  clay  formed  from  the  St.  Louis  lime- 
stone. About  3  miles  east  of  Glasgow,  on  a  plain  perhaps  75  feet  lower 
than,  the  village,  the  drift  consists  of  a  clay  with  few  pebbles  and  occasional 
bowlders,  similar  to  the  deposits  at  Columbia  noted  above.  The  depth  to 
rock  is  about  20  feet. 

The  following  records  of  deep  wells  are  from  the  drift  ridges  in  the 
eastern  part  of  the  county: 

At  W.  M.  Bartol's,  2  miles  east  of  Hecker  post-office,  a  well  60  feet 
ill  depth  is  through  till  in  the  upper  half  and  sand  in  the  lower.  A  well  at 
a  schoolhouse  in  sec.  11,  T.  3  S.,  R.  8  W.,  60  feet  in  depth,  was  mainly 
through  till,  and  one  at  a  farmhouse  a  half  mile  farther  south,  75  feet  in 
depth,  is  also  largely  till,  with  wood  at  72  feet.  A  well  made  by  F.  Yoss, 
in  sec.  36  of  this  township,  reached  a  deptli  of  115  feet,  and  is  mainly 
through  sand. 

In  the  vicinity  of  Hecker,  on  the  plain  west  of  this  ridge  and  about  30 
feet  lower  elevation,  wells  enter  rock  at  only  20  feet.  They  penetrate  a 
brf)wn  clay  containing  a  few  small  pebbles.  Water  is  usually  obtained  at 
jibout  30  feet. 


WELLS  OF  EANDOLPH  COUNTY,  ILLINOIS.  767 

RANDOLPH  COUNTY. 

GENERAL    STATEMENT.      ' 

Randolph  County  is  situated  on  the  east  border  of  the  Mississippi 
River,  immediately  below  Monroe  County,  and  has  an  area  of  ."iSO  square 
miles,  with  Chester  as  the  county  seat.  The  Kaskaskia  River  leads  south- 
ward through  its  western  portion  and  drains  the  western  half  of  the  county. 
The  eastern  part  of  the  county  is  ti'ibutary  to  Marys  River,  which  enters 
the  Mississippi  just  below  Chester. 

The  portion  of  the  county  on  the  immediate  border  of  the  Mississippi 
Valley  stands  higher  than  the  more  remote  portions  of  the  county,  there 
being  a  gradual  descent  from  the  Chester  to  the  Coal  Measures  formations, 
notwithstanding  the  fact  that  the  former  passes  beneath  the  latter.  The 
elevated  tracts  near  the  Mississippi  are  capped  with  a  porous  loess,  but  the 
lower  tracts  to  the  north  have  a  silt  nearly  as  compact  as  the  white  clay 
into  which  it  graduates  toward  the  north.  The  belt  of  ridged  drift  which 
has  been  traced  southward  through  St.  Clair  and  eastern  Monroe  counties 
crosses  the  Kaskaskia  in  northern  Randolph  County  and  passes  southeast- 
ward through  the  central  portion  of  the  county  just  south  of  the  villages  of 
Sparta  and  Steeleville.  The  belt  in  this  county  has  a  width  of  scarcely  a 
mile  and  has  less  relief  than  in  the  districts  farther  north,  its  crest  being 
seldom  more  than  50  feet,  and  usually  but  25  or  30  feet  above  the  border 
tracts. 

On  the  elevated  portion  of  the  county  outside  the  drift  ridge  just  men- 
tioned there  is  less  drift  than  in  the  lower  districts  to  the  north,  and  typical 
till  is  seldom  found.  The  valleys  are  filled  with  a  clayey  deposit,  in  which 
there  are  a  few  pebbles  and  an  occasional  bowlder.  The  uplands  have 
scarcely  a  trace  of  drift.  Along  the  belt  of  ridged  drift  and  in  the  district 
to  the  north  typical  till  is  quite  prevalent.  The  thickness  of  drift  in  the 
northern  portion  of  the  county  varies  greatly  because  of  inequalities  of  the 
underlying  rock.  Within  the  limits  of  the  village  of  Sparta  the  thickness 
varies  fully  100  feet.  Wells  frequently  obtain  water  without  entering  rock 
at  depths  of  15  to  30  feet.  In  the  elevated  portion  of  the  county  the  resi- 
dents depend  largely  upon  cistern  water,  though  it  appears  that  wells  may 
be  obtained  at  depths  of  only  50  to  75  feet. 


768  THE  ILLINOIS  GLACIAL  LOBE. 


INDIVIDUAL    WELLS!. 

At  Red  Bud,  iu  the  northwest  corner  of  the  county,  wells  usually 
obtain  water  at  about  40  feet,  and  rock  is  entered  at  12  to  20  feet.  Three 
deep  wells  have  been  sunk  at  this  village,  one  being  1,350  feet,  another 
580,  and  a  third  300  feet  in  depth.  The  deepest  well  is  sunk  on  ground 
standing  about  450  feet  above  tide,  and  water  rises  only  to  a  level  20  feet 
below  the  surface.  The  well  580  feet  in  depth  is  on  ground  30  feet  lower 
and  has  an  overflow.  The  main  supply  of  water  appears  to  be  from  the 
Chester  sandstone,  which  is  struck  in  the  deepest  well  at  230  to  290  feet, 
and  in  other  wells  at  corresponding  depths,  allowing  for  difference  in  sur- 
face elevatioi 

In  the  vicinity  of  Ruma  wells  obtain  water  from  rock  at  about  30  feet, 
there  being  onl}^  15  or  20  feet  of  loess  and  glacial  drift. 

Along  the  belt  of  ridged  drift  in  the  northwest  part  of  the  county  the 
following  sections  of  wells  were  obtained: 

Well  aections  in  drift  in  northirestem  Randolph  County,  Illinois. 

Feet. 

H.  Mehring,  sec.  6,  T.  4  S.,R.  7  W.;  mainly  till 60 

H.  Eabauack,  sec.  6,  T.  4  S.,R.  7  W.;  mainly  sandy  till 40 

P.  Ackermann,  sec.  1,  T.  4  S.,  E.  8  W. ;  bine  till  near  bottom 30 

John  Hoy,  sec.  12.  T.  4  8.,  R.  8  W. ;  sand  below  till 45 

F.  Smith,  2  miles  north  o'f  Wheaton  ;  no  rock,  on  drift  ridge 100 

C.  Klepper,  near  Wheaton ;  no  rock,  on  plain 65 

H.  Gnebert,  near  Wheaton ;  wood  and  coal  in  blue  till 47 

F.  Heitzemann,  sec.  13,  T.  4  S.,  R.  8  W. ;   bine  till  in  Iciwerpart 50 

G.Buck.sec.  19,  T.4  S.,R.7  W.;  sand  below  till 30 

F.  Rehmer,  soc.  19,  T.  4  S.,E.  7  W.;  blue  ti-ll  at  bottom .30 

F.  W.  Rehnier,  sec.  20,  T.  4  S.,  R.  7  "W. ;  entered  blue  till  at  20  feet 65 

D.  Liddy,  sec.  19,  T.  4  S.,  R.  7  W.;  mainly  clay 60 

E.  Eggerdiiig,  sec.  20,  T.  4  S.,R.  7  W. ;  mainly  bine  clay 70 

Mr.  Minch,  sec.  28,  T.  4  S.,  R.  7  W. ;  rock  at  23  feet 50 

C.  O'Hara,  sec.  27,  T.  4  S.,  R.  7  W. ;  mainly  blue  clay 75 

S.  H.  Mann,  sec.  34,  T.  4  S.,  R.  7  W. ;  shale  near  bottom 60 

J.Corseu,  sec.  1,  T.  5  S.,  R.  7  W. ;  bowlders  near  bottom 40 

J.  A.  Mann,  sec.  1,  T.  5  S.,  R.  7  W. ;  no  rock 46 

Mr.  Ore,  sec.  5,  T.  5  S.,  R.  6  W.;  uo  rock 60 

.T.Steele,  soc.  5,  T.  5  S.,  K.  6  W.;  no  rock;  blue  till  entered  at  20  feet 75 

J.  Hare,  sec.  4,  T.  5  S.,R.6  W. ;  rock  at  30  feet 60 

At  a  creamery  in  Houston  a  well  60  feet  in  depth  does  not  reach  rock. 
It  enters  a  blue  clay  containing  wood  at  about  30  feet.  A  well  near  Hous- 
ton, at  W.  McManis's,  entered  rock  at  about  57  feet.     The  lower  15  feet 


WELLS  OF  EANDOLPH  COUNTY,  ILLINOIS.  769 

was  blue  till.     A  well  at  J.  Porch's,  35  feet  in  depth,  is  mainly  through  till, 
the  lower  part  being  of  blue  color. 

A  well  on  a  knoll  in  sec.  10,  T.  4  S.,  R.  6  W.,  obtains  water  in  gravel 
at  25  feet.  A  well  near  the  base  of  the  knoll  at  15  feet  lower  elevation 
enters  rock  at  20  feet. 

At  Coulterville  wells  enter  shale  at  20  to  25  feet  and  obtain  water  at 
about  30  feet.  A  boring  1,117  feet  in  depth  obtained  brackish  water  from 
the  Chester  sandstone,  of  which  no  use  is  made  at  present.  A  complete 
record  of  strata  penetrated  is  published  in  the  Final  Report  of  Illinois  Board 
of  World's  Fair  Commissioners. 

At  Sparta  the  wells  are  seldom  more  than  30  feet  in  depth  and  obtain 
their  supply  from  the  drift.  A  boring  480  feet  in  depth  made  at  this  village 
furnishes  water  suitable  for  laundry  purposes,  but  not  for  drinking.  Several 
deep  borings  at  this  village  obtain  a  supply  of  gas  from  the  base  of  the. 
Chester  limestone  at  840  to  864  feet.  The  drift  at  these  borings  ranges 
from  34  feet  to  116  feet,  the  thickest  being  on  the  lowest  ground  (J.  M. 
Nickles). 

A  coal  shaft  near  Eden  Station  penetrated  a  complicated  series  of  drift 
beds,  a  section  of  which  appears  on  page  117 

At  Steeleville  wells  are  usually  obtained  at  18  to  22  feet  from  sandy 
beds  in  the  drift.  An  artesian  well  312  feet  in  depth  enters  rock  at  60  feet 
and  furnishes  water  of  good  quality  for  drinking.  The  well  overflows  at 
the  rate  of  about  2  gallons  per  minute.  A  complete  section  of  the  strata 
penetrated  by  this  well  is  published  by  Professor  Nickles  in  the  report 
of  the  Illinois  Board  of  "World's  Fair  Commissioners. 

Wells  along  the  drift  ridge  both  north  and  south  from  Steeleville  have 
been  sunk  to  depths  of  40  or  50  feet  without  entering  rock.  They  are 
mainly  through  till. 

At  Shiloh  Hill,  wMch  stands  on  the  outer  border  of  the  belt  of  ridged 
drift,  wells  have  been  sunk  to  a  depth  of  35  feet,  in  some  cases  penetrating 
wood  near  the  bottom  below  till. 

At  Wine  Hill,  on  a  prominent  point  in  the  southern  part  of  the  county, 
a  well  is  reported  to  have  been  sunk  to  a  depth  of  36  feet  without  entering 
rock,  but  rock  is  exposed  in  that  vicinity  at  depths  of  20  to  30  feet. 

3ION   XXXVTII 49 


770  THE  ILLINOIS  GLACIAL  LOBE. 


WASHINGTON    COUNTY. 
GENERAL    STATEIMENT. 


Washington  County  is  situated  northeast  of  Randolph  and  east  of 
St.  Clair  County,  with  Nashville  as  the  county  seat,  and  has  an  area 
of  540  square  miles.  The  Kaskaskia  River  forms  a  poi-tion  of  the  north 
border  and  receives  the  di-ainage  of  the  greater  part  of  the  county.  The 
southeast  part  of  the  county  drains  southward  through  Beaucoup  Creek, 
a  tributary  of  the  Big  Muddy  River.  The  uplands  are  coated  with 
white  clay  scarcely  as  compact  as  that  which  is  found  in  counties  north 
and  east. 

The  drift  masks  the  preglacial  ridges  and  hills  without  entirely 
concealing  them.  The  drainage  lines  are  probably  in  large  part  along 
preglacial  courses,  but  at  levels  above  the  old  rock  floor.  On  the  uplands 
or  preglacial  ridges  the  drift  is  only  10  or  20  feet  in  depth,  but  along  the 
main  preglacial  valleys  it  probably  exceeds  100  feet.  Wells  usually  enter 
rock  a  few  feet  on  the  uplands,  but  on  the  lowlands  and  along  valleys  they 
obtain  water  from  the  drift.     The  depth  rarely  exceeds  40  feet. 


INDIVIDUAL   WELLS. 


At  Nashville  the  wells  range  in  depth  from  14  to  45  feet  and  usu- 
ally enter  rock  a  few  feet.  The  strongest  ones  are  estimated  to  have 
a  capacity  of  100  barrels  a  day,  but  many  will  yield  not  more  than  10 

barrels. 

In  the  vicinity  of  Hoyleton  the  drift  is  15  to  30  feet  in  depth  and 
many  wells  are  sunk  into  the  underlying  rock,  obtaining  water  at  about  40 
feet.     They  are  largely  thi-ough  till  of  brownish  yellow  color. 

In  the  vicinity  of  Ashley  wells  range  in  depth  from  8  feet  to  about 
40  feet.  Rock  is  entered  at  15  or  20  feet,  and  the  drift  is  mainly  a 
brown  till. 

In  the  southern  part  of  the  county  the  distance  to  rock  is  usually  but 
12  to  20  feet  and  wells  not  infrequently  penetrate  it  a  few  feet.  A  few 
knolls  southwest  of  Oakdale  appear  to  have  no  rock  nucleus,  but  informa- 
tion concerning  them  is  unsatisfactory. 

In  the  northwest  part  of  the  county,  on  the  borders  of  the  Kaskaskia, 
wells  are  obtained  without  entering  rock,  at  depths  of  20  or  30  feet. 


WELLS  OF  PERRY  COUNTY,  ILLINOIS.  771 


PERRY  COUNTY. 

GENERAL    STATEMENT. 


Peny  County  is  situated  south  of  Washing-ton  and  east  of  Randolph 
County,  with  Pinckneyville  as  the  county  seat,  and  has  an  area  of  440 
square  miles.  The  greater  portion  of  the  county  is  tributary  to  the  Big- 
Muddy  River  through  Beaucoup  Creek,  which  traverses  the  central  part  of 
the  county  in  a  north-to-south  course.  The  Little  Muddy  forms  the  east 
border  of  the  county  south  from  the  Jefferson  County  line.  A  few  square 
miles  in  the  west  part  of  the  county  drain  southwestward  through  Marys 
River  to  the  Mississippi.  The  uplands  are  coated  with  compact  white  clay, 
but  the  valleys  have  a  more  porous  deposit,  forming  a  rich  black  soil. 

The  features  of  this  county  are  very  similar  to  those  of  Washington, 
the  preglacial  ridges  being  but  partially  concealed  by  the  drift  and  having 
a  coating  only  10  to  20  feet  thick  on  the  highest  portion,  while  the  valleys 
are  filled  more  deeply  so  that  wells  seldom  enter  the  rock.  Water  is  usually 
obtained  at  less  than  40  feet,  either  from  the  drift  or  rock. 

INDIVIDUAL    WELLS. 

The  public  water  supply  at  Pinckneyville  is  obtained  from  an  artesian 
well  around  the  mouth  of  which  a  large  well  is  excavated  which  receives 
the  water.  The  well  is  reported  by  the  Manual  of  American  Waterworks 
to  have  a  depth  of  2,000  feet,  and  to  be  used  principally  for  fire  protection 
and  street  sprinkling.  Private  wells  in  that  vicinity  are  obtained  at  about 
30  feet.     Rock  is  occasionally  entered  at  less  than  20  feet. 

In  the  northwest  part  of  the  county,  near  Swanwick,  wells  usually 
obtain  water  at  slight  depth  in  the  rock,  the  drift  being  often  not  more  than 
10  or  12  feet  in  depth. 

In  the  southwest  part  of  the  county  wells  in  several  instances  have 
encountered  a  blue  mud  carrying  a  large  amount  of  wood.  This  appar- 
ently underlies  the  pebbly  clays  of  the  drift,  but  whether  it  in  turn  is  under- 
laid by  a  till  sheet  is  not  ascertained. 

In  the  vicinity  of  Duquoin  wells  range  in  depth  from  15  to  40  feet, 
the  usual  depth  being  about  25  feet.  They  very  seldom  reach  the  rock. 
Coal  shafts  in  that  vicinity  usually  penetrate  30  to  45  feet  of  drift.  The 
Manual  of  American  Waterworks  (1897)  reports  that  waterworks  are  under 
construction. 


772 


THE  ILLINOIS  GLACIAL  LOBE. 


lu  the  spring  of  1897  a  boring  was  begun  at  St.  Johns  by  the  IlHnois 
Central  Coal  and  Salt  Company  wliich  at  last  reports  had  reached  a  depth 
of  more  than  3,600  feet,  and  the  drilling  was  still  in  progress.  So  far  as 
the  writer  is  aware,  it  is  not  exceeded  in  depth  by  any  other  boring  in 
Illinois.  The  detailed  record  to  a  depth  of  2,275  feet,  which  is  given 
below,  was  furnished  by  John  Forester,  superintendent  of  the  company,  in 
July,  1898.  Since  then  Mr.  Forester  has  communicated  the  general  results 
from  time  to  time.  A  limestone  formation  forms  the  lower  part  of  the  sec- 
tion below  the  point  where  the  detailed  record  ends.  Mr.  Forester  states 
that  a  good  quality  of  fresh  water  was  found  at  a  depth  of  311  feet,  but  in 
such  limited  quantity  that  it  was  soon  exhausted  by  a  pump  of  15-gallon  per 
minute  capacity.  -At  520  feet  water  was  encountered  which  showed  15  per 
cent  salt.  Below  this  depth  the  sahnity  gradually  increased  until  at  980 
feet  it  reached  34  per  cent.  This  water  was  cased  out  at  1,000  feet,  and 
A^ery  little  more  was  encountei'ed  until  a  depth  of  1,604  feet  was  reached, 
when  a  vein  of  water  with  38  per  cent  salt  was  struck.  The  well  continued 
to  yield  this  water  until  a  bed  of  "fii-e  clay"  was  reached  at  1,949  feet. 
After  passing  through  20  feet  of  fire  clay  another  yield  of  water  with  38  per 
cent  salt  was  found,  which  continued  to  a  bed  of  shale  at  2,026  feet.  No 
more  water  was  found  until  a  depth  of  2,271  feet  was  reached,  when  a 
vein  of  the  same  salinity  was  sti'uck.  At  this  depth  there  was  apparently  a 
crevice  in  the  rock  lined  with  crystals  of  calcite.  As  yet  no  identifications 
of  the  geological  formations  have  been  made.  Temperature  tests  were 
made  by  Mr.  Forester,  in  March,  1899,  when  the  boring  had  reached  a  depth 
of  3,600  feet.  After  an  exposure  of  two  hours  the  thermometer  registered 
93*^  F.,  and  after  an  exposure  of  twenty-four  hours  101°  F. 

Log  of  deep  boring  at  St.  Johnu,  Illmoia. 


Glacial  drift . . . 

Lime  rock 

Sandy  shale  .  - . 
Shale  and  co.al 
Sandy  shale  . . . 

Clay  shale 

Sandy  shale  . , 
.Sand  lock 


Thick- 


Feel. 
42 

3 

16 
10 
25 
30 
80 
15 


Septl 

■ 

Feet. 

1 

0- 

42 

42- 

45 

45- 

61 

61- 

71  1 

71- 

96  1 

96- 

126 

126- 

206 

206- 

221 

Sandy  shale 

Fire  clay  and  shale 

Shale  with  partings 

Sand  rock,  frt'sli  water 

Lime  rock 

Sand  rock,  15  per  cent  salt.. 

Saudy  shale 

Sand  rock 


Thick- 
11  ess. 


Depth. 


Feet. 
23 
12 
55 
178 
31 
15 
28 
15 


1 


Feet. 

221-  244 
244-  256 
256-  311 
311-  489 
489-  520 
520-  535 
535-  563 
563-  578 


WELLS  OF  JEFFERSON  COUNTY,  ILLINOIS. 

Lofi  of  deep  horing  at  St.  Johns.,  Illinois — Continued. 


773 


Saudy  shale. 
Lime  rock . . . 
SaBdrock... 

Shale 

Saud  rock... 
Lime  rock... 
Sand  rook.. . 
Clay  shale  . . 
Sandy  shale - 
Mixed  shale  - 
Lime  rock . . . 

Shale 

Lime  rock.. . 
Clay  shale  . . 

Lime  rook 

Sandy  shale . 
Clay  shale  . . 
Sandy  shale . 
Lime  rock . . . 
Sand  rock . . . 
Lime  rock . . . 
Sandy  shale . 
Sand  rock... 
Sandy  shale  . 

Lime  rock 

Eed  marl . . . . 
Saud  rock... 
Sandy  shale . 
Sand  rock... 
Soft  shale  . . . 
Sand  rock . . . 
Blue  lime  . . . 
Sand  rock .. . 


Thick- 
ness. 


Feet. 
32 

8 
25 
13 
10 

3 

10 
30 
35 
35 
16 
20 
25 
15 

5 
15 
40 
67 
20 
20 
10 
22 
13 
■  20 
20 

4 

39 
40 
90 
10 
10 


Depth 


Feet. 

578-  610 
610-  618 
618-  643 
643-  656 
656-  666 
666-  669 
669-  679 
679-  709 
709-  744 
744-  779 
779-  795 
795-  815 
815-  840 
840-  855 
855-  860 
860-  875 
875-  915 
915-  982 
982-1,  002 


1,  002-1 
1,  022-1 
1,  032-1 
1,  054-1 
1,  067-1 
1,  087-1 
1, 107-1 
1, 111-1 
1, 150-1 
1, 190-1 
1,  280-1 
1, 290-1, 
1,  300-1 
1,  305-1 


022 
032 
054 
067 
087 
107 
111 
150 
190 
280 
290 
300 
305 
310 


Shale 

Sand  rock 

Shale 

Eed  marl 

Shale 

Lime  rook 

Shale 

Sand  rock 

Lime  rock 

Sand  rock 

Lime  rock 

Shale  with  partings 

Lime  rock 

Shale 

Sand  rock 

Shale,  mixed 

Lime  rock 

Sandy  shale 

Lime  rock 

Shale 

Lime  rock,  38  per  cent  .*alt.. 

Shale 

Lime  rock,  38  per  cent  salt . . 

Fire  clay  or  shale 

Lime  rock  with  partings 

Shale 

Lime  rock  with  partings 

Sandy  lime  rock 

Light  gray  lime  rock 

Spar,  calcite  crystals 

Light  gray  lime  rock,  hard . . 
Light  gray  lime  rock,  soft  . . 
Mainly  limestone  to  3,600  feet 


Thick- 


Feet. 

10 

10 

14 

4 

4 

16 

7 

14 

10 

15 

6 

20 

35 

23 

20 

19 

4 

8 

40 

15 

92 

3 

250 

20 

57 

10 

102 

160 

63 

4 

498 

227 

600 


Depth. 


Feet. 
1,  310-1,  320 

1,  320-1, 330 
1,  330-1,  344 
1,  344-1,  348 
1,  348-1,  352 
1,  352-1,  368 
1,  368-1,  375 
1,  37.5-1,  389 
1,  389-1,  399 
1,  399-1,  414 
1,  414-1.  420 
1,  420-1,  440 
1, 440-1,  475 
1,  47.5-1, 498 
1, 498-1,  518 
1,  518-1,  537 
1,  537-1,  541 
1,  541-1,  549 
1,  549-1,  589 
1,  589-1,  604 
1,  604-1,  696 
1,  696-1,  699 
1,699-1,949 
1,  949-1,  969 

1,  969-2, 026 

2,  026-2,  036 
2,  036-2, 148 
2, 148-2,  208 
2,  208-2,  271 
2,  271-2,  275 
2,  275-2,  773 

2,  773-3, 000 

3,  000-3,  600 


Altitude  of  well  mouth,  463  feet  above  tide. 


JEFFERSON    COUNTY. 
GENERAL    STATEMENT. 


Jefferson  Countj  is  situated  east  of  Washington  and  Perry  counties, 
about  midway  between  the  Mississippi  and  Wabash  rivers,  with  Mount 
Vernon  as  the  county  seat,  and  has   an  area  of  580  square  miles.     The 


774  THE  ILLINOIS  GLACIAL  LOBE. 

di-ainage  is  mainly  soutliward  tkrough  the  Big  Muddy  River.  A  small  area 
in  the  northeast  part  is  tributary  to  Skillett  Fork,  which  flows  southeast  to 
the  Little  Wabash.  The  uplands  are  coated  with  white  clay,  which  furnishes 
a  slow  absorbent  for  the  rainfall.  The  portions  of  the  county  remote  from 
the  main  drainage  lines  have  imperfect  drainage,  the  excess  of  rainfall  being 
disposed  of  largely  by  evaporation. 

The  glacial  deposits  are  generally  thin  and  but  partially  conceal  the 
preglacial  ridges  and  valleys.  They  consist  cliiefly  of  a  brownish  yellow 
till.  Throughout  much  of  the  county  wells  are  reported  to  penetrate  rock 
a  few  feet  for  the  best  supply,  but  weak  wells  are  often  supplied  fi-om  the 
diift.     No  attempt  was  made  to  collect  well  records  in  the  county. 

The  Manual  of  American  Watei-works  reports  that  at  Mount  Vernon 
the  public  water  supply  is  from  impounded  water.  The  drift  in  the  vicinity 
of  that  city  is  only  10  or  15  feet  in  depth. 

WAYNE    COUNTY. 
GENERAL    STATEMENT. 

Wayne  County  is  situated  in  the  southeast  part  of  the  State,  with 
Fairfield  as  the  county  seat,  and  has  an  area  of  720  square  miles.  The 
Little  Wabash  River  leads  southward  near  the  eastern  border  of  the  county 
and  Skillett  Fork  leads  southeastward  thi'ough  the  southwestern  portion. 
The  uplands  are  covered  with  a  silt  deposit,  but  as  the}"  are  more  hilly  than 
the  counties  to  the  north  and  west  the  water  is  drained  to  the  lowlands 
readily,  and  a  more  compact  deposit  is  found  on  the  lowlands  than  on  the 
hills  or  uplands. 

The  drift  is  generally  a  thin  coating  averaging  scarcel}''  15  feet  in 
depth  on  the  higher  parts  of  the  county.  In  the  lowlands  and  along  val- 
ley's there  is  probably  a  greater  depth.  The  thickness,  however,  has  not 
been  tested  by  well  borings,  the  wells  being  obtained  at  comparatively 
slight  depth  from  sandy  beds  in  the  drift.  The  di-ift  consists  usually  of  a 
brown  till,  which  sets  in  below  the  white  clay  or  surface  silt  at  a  depth  of 
6  or  8  feet. 

INDIVIDUAL    WELLS. 

In  the  northwest  part  of  the  county,  in  the  vicinity  of  Rinard,  Blue 
Point,  and  Johnsonville,  a  large  percentage  of  the  wells  enter  rock  at  about 
10  feet  and  obtain  water  at  30  to  40  feet  or  less. 


WELLS  OF  EDWARDS  AND  WABASH  COUNTIES,  ILLINOIS.      775 

In  the  vicinity  of  Cisne  the  drift  has  a  thickness  of  20  feet  or  more. 
Between  Cisne  and  Fairfield,  however,  rock  is  often  entered  at  10  or  12 
feet.     The  drift  is  also  thin  from  Fairfield  westward  to  Wayne  City. 

In  the  city  of  Faii-field  the  drift  ranges  in  thickness  from  8  to  about 
20  feet.  Wells  usually  obtain  water  from  rock  at  25  feet  or  less.  A  few 
are  drilled  to  a  depth  of  50  or  even  70  feet. 

East  from  Fairfield,  in  the  vicinity  of  Meriam,  wells  enter  rock  at  10 
feet  or  less.  At  Grolden  Gate  Station,  which  stands  on  a  low  hill  in  the 
Little  Wabash  Valley,  rock  is  struck  at  16  to  20  feet. 

EDWARDS   AND   WABASH   COUNTIES. 
GENERAL   STATEMENT. 

These  two  counties,  with  a  combined  area  of  but  440  square  miles, 
are  situated  east  of  Wayne  County  and  border  the  Wabash  River.  Albion 
is  the  county  seat  of  Edwards,  and  Mount  Carmel  tlie  county  seat  of 
Wabash  County,  The  Bonpf^s  River  forms  the  dividing  line  between  the 
counties  and  flows  through  a  broad  bottom  deeply  filled  with  drift  or  allu- 
vium. This  stream  receives  the  drainage  of  much  of  both  counties  and 
carries  it  southward  to  the  Wabash.  The  western  portion  of  Edwards 
County  drains  into  the  Little  Wabash  River  and  the  eastern  portion  of 
Wabash  County  into  the  main  Wabash  River. 

Both  counties  are  covered  thinly  with  diift  excejit  in  lowlands  or 
valleys,  and  the  preglacial  ridges  and  hills  stand  50  to  100  feet  or  more 
above  the  neighboring  lowlands.  There  is  a  silt  covering  these  hills  and 
ridges,  but  it  is  more  porous  than  the  white  clay.  On  the  lowlands  and 
flat  areas  within  these  counties  the  white  clay  apjDears  in  its  compact  phase. 
Wells  are  usually  obtained  on  the  loAvIands  at  a  depth  of  20  feet  or  less 
without  entering  rock.  On  the  uplands  few  wells  are  obtained  without 
penetrating  rock.  The  depth,  however,  is  moderate,  seldom  exceeding 
50  feet. 

INDIVIDUAL    WELLS. 

Near  Ellery,  in  western  Edwards  County,  at  the  base  of  the  east  blufl" 
of  the  Little  Wabash,  rock  is  usually  entered  at  10  to  20  feet,  and  wells 
obtain  water  at  about  30  feet.  On  the  bluif  east  of  Ellery,  at  an  altitude 
60  feet  above  the  station,  wells  enter  rock  at  about  10  feet  and  obtain 
water  at  40  or  50  feet. 


776  THE  ILLINOIS  GLACIAL  LOBE. 

At  the  villag'e  of  Albion,  whicli  is  situated  ou  the  divide  between  the 
Bonpas  and  Little  Wabash,  at  an  altitude  about  150  feet  above  the  streams, 
rock  outcrops  in  numerous  places,  and  the  g'eneral  thickness  of  the  drift 
coating  scarcelj"  exceeds  5  feet.  "Wells  are  obtained  at  deoths  of  40  or  50 
feet,  but  the  residents  depend  mainh-  upon  cisterns. 

In  the  valley  of  Bonpas  River,  near  Brown  Station,  a  well  reached  a 
depth  of  61  feet  without  entering-  rock.  It  is  reported  to  be  mainly  tlii'ough 
sand  with  few  if  any  pebbles. 

At  West  Salem  rock  is  visually  entered  in  wells  at  20  feet  or  less,  and 
water  is  obtained  at  30  or  40  feet. 

At  Mount  Carmel  the  supply  for  the  waterworks  is  obtained  from  a 
well  in  the  Wabash  Valley,  which  obtains  Avater  at  the  surface  of  the  rock 
at  a  depth  of  25  feet.  Wells  on  the  uijlands  in  the  cit}"  obtain  water  fi'om 
the  rock  at  depths  of  25  to  40  feet,  those  on  the  lowlands  near  the  Wabash 
obtain  water  from  di-ift  at  a  deptli  of  15  to  25  feet.  West  from  Mount 
Carmel,  in  the  vicinity  of  Maud  and  Belmont  stations,  wells  in  some  cases 
obtain  water  in  drift  at  15  to  25  feet,  but  often  enter  the  rock  a  few  feet. 

At  Friendsville  rock  is  struck  at  12  to  15  feet  and  wells  obtain  water 
at  about  30  feet.  In  a  lowland  tract  2  miles  northeast  of  Friends\-ille, 
known  as  Crawfish  Flats,  wells  40  feet  in  depth  do  not  reach  rock,  and  logs 
are  sometimes  struck  near  the  bottom. 

WHITE    COUNTY. 
GENERAL    STATEMENT. 

White  County  is  situated  on  the  west  border  of  the  Wabash  River,  in 
the  southeast  part  of  the  State,  immediately  below  Edwards  County,  and  has 
an  area  of  500  square  miles,  with  Carmi  as  the  county  seat.  The  Little 
Wabash  River  traverses  the  county  from  north  to  south  nearly  centrally, 
and  Skillett  Fork,  the  main  tributary  of  Little  Wabash,  lead.s  southeast- 
ward across  the  northwestern  part  of  the  county  and  enters  the  Little 
Wabash  just  above  the  town  of  Carmi.  In  this  county  the  streams  are 
bordered  by  Ijroiid  lowlands,  filled  apparently  to  considerable  de})th  with 
glacial  or  alluvial  deposits.  The  uplands  are  hilly  and  carry  a  very  thin 
coating  of  di'ift,  rock  usually  being  entered  within  10  feet  of  tlie  surface. 
The  entire  countA'  appears  to  have  been  covered  by  the  ice  sheet,  for  drift 
is  found  in  the  vicinity  of  the  Wabash  River  both  to  the  east  and  south  of 


WELLS  OF  WHITE  COUNTY,  ILLINOIS.  777 

the  county  limit  in  Posej^  County,  Indiana,  and  Gallatin  County,  Illinois. 
The  drift  is  mainly  a  brown  till  on  which  there  is  a  coating  of  silt  6  or  8 
feet  in  depth,  which  is  probably  the  southward  extension^  ot  the  white 
clay,  though  a  more  porous  deposit. 

Wells  are  obtained  on  the  uplands  at  moderate  depths  in  the  rock.  On 
the  lowlands  they  are  shallow,  seldom  exceeding  30  feet,  and  obtain  water 
from  gravel  or  sand.  Along  the  Wabash  there  is  an  extensive  bottom 
underlain  by  fine  gravel  which  affords  water  at  about  the  level  of  the 
river. 

INDIVIDUAL    WELLS. 

The  jxiblic  water  supply  at  Carmi  is  pumped  from  the  Little  Wabash 
River.  On  the  hills  bordering  the  city  wells  enter  rock  at  about  1 0  feet  and 
water  is  obtained  at  '26  to  40  feet.  ■  These  conditions  prevail  southwestward 
to  the  limits  of  the  county. 

In  the  south  part  of  the  county,  in  Heralds  Prairie  Township,  there  is 
considerable  lowland,  and  wells  occasionally  reach  a  depth  of  40  feet  without 
entering  rock;  they  are  mainly  through  till. 

In  the  Wabash  bottoms,  in  the  vicinity  of  Concord,  (Emma  post-office) 
the  wells  range  in  depth  from  15  to  40  feet  and  are  mainh^  through  sand. 
About  3  miles  east,  of  this  village  wells  obtain  water  in  gravel  at  a  depth  of 
biit  12  to  20  feet. 

In  the  vicinity  of  Crossville  and  Phillipstown,  northeast  from  Carmi, 
wells  obtain  water  at  about  25  feet  in  sand.  A  section  near  Phillipstown  is 
noted  in  the  Greology  of  Illinois,  which  exposes  loess  with  fossils,  20  or  30 
feet,  beneath  which  is  drift  with  pebbles  and  small  granite  bowlders,  35  feet. 

At  Grrayville,  in  the  northeast  corner  of  the  county,  the  loess  has  a 
thickness  of  16  or  more  feet  and  is  underlain  by  a  thin  sheet  of  till.  Wells 
usually  enter  the  rock,  obtaining  water  at  30  to  40  feet.  The  waterworks 
obtains  its  supply  from  the  Wabash  River.  ^ 

HAMILTON    COUNTY. 
GENERAL    STATEMENT. 

Hamilton  County  is  situated  west  of  White  County,  in  the  southeastern 
portion  of  the  State  and  has  an  area  of  440  square  miles,  with  McLeans- 
boro  as  the  county  seat.     Its  southeast  portion  is  drained  by  the  north  fork 

'  Manual  of  Anierioau  Waterworks.  1S97. 


778  THE  ILLINOIS  GLACIAL  LOBE. 

of  Saline  River  and  the  northern  portion  is  tributary  to  Skillett  Fork  of 
Little  Wabash  River.  The  lowlands  are  filled  to  considerable  depth  with 
drift,  but  the  uplands,  like  those  of  White  and  the  neighboring  counties  on 
the  north  and  east,  have  a  very  thin  drift  coating,  averaging  scarcely  10 
feet.  The  surface  of  the  uplands  is  uneven,  the  preglacial  ridges  and  hills 
being  concealed  but  little  by  drift.  A  coating  of  silt  covers  the  county, 
but  it  is  much  more  porous  than  that  of  the  more  level  counties  on  the 
northwest. 

WELLS. 

The  wells  of  this  county,  as  in  neighboring  counties,  obtain  water  at 
depths  of  but  20  to  40  feet  or  even  less,  those  on  the  uplands  being  gener- 
ally into  rock  a  few  feet,  while  these  on  the  lowlands  are  obtained  without 
reaching  the  rock.     No  records  of  individual  wells  were  collected. 

The  village  of  McLeansboro  has  a  fire  protection  in  cisterns  distributed 
around  the  public  square.  There  are  also  four  tubular  wells  in  the  village, 
Avhich,  the  mayor  reports,  have  hard  water,  unfit  for  domestic  use.  The 
greater  part  of  the  citizens  depend  upon  cistern  water. 

FRANKLIN    COUNTY. 
GENERAL    STATEMENT. 

Franklin  County  is  situated  south  of  Jefterson,  about  midway  between 
the  Wabash  and  Mississippi  rivers,  with  Benton  as  the  county  seat,  and  has 
an  area  of  430  square  miles.  It  is  drained  southwestward  by  the  Big 
Muddv  River,  which  crosses  the  west-central  portion  of  the  county.  Its 
topography  and  general  characteristics  are  so  similar  to  Hamilton  County 
that  further  description  is  scarcely  necessary. 

The  wells  on  the  uplands  usually  enter  rock  at  a  slight  depth  and 
penetrate  it  a  few  feet.  If  a  good  quality  of  water  is  not  obtained  cistern 
water  is  substituted.  In  the  flats  of  the  Big  Muddy  Valley,  in  tlie  south- 
west part  of  the  county,  wells  may  be  obtained  without  entering  the  rock. 

JACKSON     COUNTY. 
GENERAL    STATEMENT. 

Jackson  County  is  situated  on  the  east  border  of  the  Mississippi  River 
below  Randolph  County,  with  Murpliysboro  as  the  county  seat,  and  has  an 


WELLS  OF  JACKSON  COUNTY,  ILLINOIS.  779 

area  of  580  square  miles.  Big-  Muddy  River  traverses  its  southern  portion 
and  Beaucoup  Creek  divides  the  northern  portion  nearly  centrally.  This 
county,  like  Randolph,  has  an  elevated  limestone  tract  along  the  Mississippi 
bluffs,  from  which  there  is  a  descent  northeastward  to  the  plains  underlain 
by  the  Coal  Measures.  The  elevated  portion  of  this  county  has  such  a 
broken  surface  that  it  is  but  sparsely  settled.  At  the  south  it  extends  beyond 
the  glacial  boundary  and  preserves  all  the  ruggedness  of  the  preg-lacial 
topography.  The  western  portion  appears  to  have  been  covered  by  the  ice 
sheet,  but  the  drift  only  partially  fills  the  preglacial  valleys. 

The  belt  of  ridged  drift  which  has  been  traced  southeastward  across 
Randolph  County  to  the  border  of  this  county  is  represented  by  occasional 
low  ridges  and  knolls  along  the  north  border  of  the  elevated  tract  just  dis- 
cussed as  far  east  as  the  plain  bordering  Beaucoup  Creek.  The  best 
development  is  found  1  to  4  miles  southeast  of  Ava,  along  the  turnpike 
leading  from  Ava  to  Murphysboro.  The  belt  has  not  been  identified  in  the 
eastern  portion  of  the  county.  Northeast  from  this  ridged  belt  there  is 
generally  present  a  sheet  of  typical  till  20  to  40  feet  or  more  in  depth,  and 
a  similar  deposit  is  found  in  the  lowlands  of  the  northeastern  part  of  the 
county.  The  wells  often  penetrate  a  bed  of  blue  silt  containing  wood  at 
depths  of  30  feet  or  more,  beneath  the  pebbly  glacial  clays.  Several 
instances  are  noted  in  the  Geology  of  Illinois,  and  other  instances  came  to 
the  writer's  notice,  but  no  exposures  of  the  silt  were  found  b}^  the  writer. 

On  the  elevated  and  hilly  portions  of  the  county  the  residents  depend 
largely  upon  cistern  water,  but  a  few  wells  have  been  obtained  at  moderate 
depth.  In  the  lower  portions  of  the  county  wells  are  obtained  at  20  to  50 
feet,  often  without  entering  rock.  Those  in  the  Mississippi  Valley  are  30 
to  40  feet  in  depth  and  mainly  through  a  fine  sand. 

INDIVIDUAL    WELLS. 

The  wells  at  Campbell  Hill,  in  the  northwest  part  of  the  county,  have 
in  a  few  instances  been  sunk  into  rock,  which  is  reached  at  a  depth  of  about 
40  feet.  The  majority,  however,  obtain  water  from  the  glacial  drift. 
Records  of  wells  near  this  village  appear  in  the  Greology  of  Illinois,  in 
which  a  blue  mud  containino-  wood  is  struck  below  the  g-lacial  di-ift  at 
depths  of  30  to  35  feet. 


780  THE  ILLINOIS  GLACIAL  LOBE. 

At  Ava  a  coal  boring-  is  thought  to  have  struck  rock  at  57  feet,  but  the 
deepest  Avells  at  this  village  are  about  60  feet  and  do  not  enter  rock.  They 
are  mainly  through  a  pebbly  clay  witli  which  thin  sand  beds  are  associate;!. 
A  well  at  D.  R.  Wills's,  on  the  crest  of  the  drift  ridg-e,  3  miles  southeast 
of  Ava,  reached  a  depth  of  65  feet  without  entering  rock.  Its  altitude  is 
fully  300  feet  above  the  Mississippi  River.  Within  2  miles  east  from  this 
well  rock  is  struck  at  only  15  to  25  feet,  on  gi-ound  fully  as  elevated  as  the 
drift  ridge.  Immediately  outside  the  drift  ridge  there  is  scarcely  any  drift 
covering  the  rock. 

At  Murphysboro  wells  are  usually  obtained  at  15  to  30  feet  from  sand 
below  clay.  Coal  borings  and  the  well  at  the  Murphysboro  brewery  pene- 
trate considerable  sand  and  seldom  reach  rock  at  less  than  100  feet.  The 
boring  at  the  brewery  penetrated  132  feet  of  drift.  An  artesian  well  was 
sunk  at  this  city  many  years  ago  which  reached  a  depth  of  1,800  feet.  A 
flow  of  salt  water  was  struck  at  about  1,300  feet.  The  waterworks  obtains 
its  supply  from  Big  Muddy  River. 

At  Carbondale  the  wells  are  usually  obtained  at  15  to  20  feet  in  a 
sandy  clay  near  the  base  of  the  drift.  A  well  at  the  Newell  House  entered 
rock  at  22  feet  and  reached  a  depth  of  50  feet.  A  well  at  the  electric  light 
plant  is  reported  to  have  penetrated  44  feet  of  di-ift,  mainh^  a  clay  with  few 
pebbles. 

At  Elkville,  in  the  northeast  part  of  the  county,  wells  are  obtained 
at  about  20  feet  from  sandy  beds  associated  with  the  till.  A  coal  boring  at 
this  village,  reported  in  the  Geology  of  Illinois,  entered  rock  at  34  feet. 

WILLIAMSON  COUNTY. 
GENERAL    STATEMENT. 

Williamson  County  is  situated  east  of  Jackson,  with  Marion  as  the 
county  seat,  and  has  an  area  of  440  square  miles.  The  western  half  of  the 
county  is  tributary  to  Big  Muddy  River  and  the  eastern  to  Saline  River. 
With  the  exception  of  the  south  border,  which  is  hilly  and  unglaciated,  this 
county  is  a  low  plain  covered  to  a  moderate  depth  with  glacial  drift.  The 
thickness  of  the  drift  apjiears  to  be  slightly  greater  than  in  counties  to 
the  north,  l)ut  it  is  not  often  more  than  40  feet.  The  average  is  probably 
25  feet.     A  capping  of  silt  nearly  as  compact  as  the  white  clay  covers  the 


WELLS  OP  WILLIAMSOS^  COUNTY,  ILLIISrOIS.  781 

glacial  di-ift.  Where  drainage  lines  are  not  well  developed,  tlie  excess  of 
rainfall  is  largely  disposed  of  by  evaporation.  The  poorest  drainage  is 
found  in  the  northwest  part  of  the  county,  where  there  is  an  extensive  plain 
standing  but  a  few  feet  above  the  level  of  Big  Muddy  River.  In  this 
portion  of  the  county  wells  usually  obtain  water  without  entering  rock,  but 
in  the  eastern  and  southern  portions  the  majority  enter  rock. 

INDIVIDFAL    WELLS. 

In  the  vicinity  of  Marion  wells  are  obtained  in  sand  below  till  at 
about  20  feet.  They  penetrate  6  or  6  feet  of  white  clay,  then  enter  a 
yellow  till  which  extends  to  the  water-bearing  sand.  In  a  few  cases  blue 
till  is  entered  at  about  20  feet.  These  conditions  prevail  over  the  portion 
of  the  county  north  and  west  from  Marion. 

In  the  portion  of  the  county  south  and  west  from  Marion  low  hills  with 
rock  nucleus  rise  above  the  level  of  the  drift  filling,  but  the  plain  tracts 
among  these  hills  are  filled  to  a  depth  of  50  to  75  feet  or  more  with  glacial 
drift.  A  well  near  Cottage  Home,  in  the  southwest  township  of  the  county, 
within  3  miles  of  the  glacial  boundary,  j^enetrated  68  feet  of  drift,  mainly 
blue  till,  and  obtained  water  without  entering  rock.  Several  wells  in  that 
vicinity  are  30  to  40  feet  in  depth  without  entering  rock. 

In  the  eastern  part  of  the  county  there  are  low  hills  with  rock  nucleus 
on  which  the  drift  coating  is  only  a  few  feet  in  depth,  but  among  these  hills 
the  wells  often  reach  a  depth  of  30  feet  without  entering  rock  and  are  largely 
tln-ough  a  brown  till. 

In  the  unglaciated  portion  on  the  south  border  of  the  county  there  are 
few  residents,  and  these  depend  chiefly  upon  cistern  water  or  springs. 

SALINE   COUNTY. 
GENERAL    STATEMENT. 

Saline  County  is  situated  east  of  Williamson  and  has  an  area  of  380 
square  miles,  with  Harrisburg  as  the  county  seat.  It  is  drained  by  Saline 
River,  whose  south  fork  passes  eastward  across  the  southern  j)ortion  of  the 
county  and  whose  north  fork  crosses  the  northeast  corner.  The  portion  of 
the  county  south  of  the  south  fork  is  an  elevated  and  hilly  region,  largely 
unglaciated ;  the  remainder  of  the  county  is  a  low  district  with  small  hills 


782  THE  ILLINOIS  GLACIAL  LOBE. 

and  ridges  having  I'ock  nuclei,  but  which  rise  only  25  to  50  feet  above  the 
bordering  lowlands.  The  streams  are  generally  bordered  b}'  broad  low- 
lands, poi'tious  of  which  are  thinly  covered  with  drift,  as  are  also  the  low 
hills  and  ridges  just  mentioned.  There  are  probablv  filled  valleys  travers- 
ing these  lowlands,  in  which  the  thickness  of  drift  is  greater  than  on  the 
remainder  of  the  county.  In  tliis  county,  as  in  the  neighboring  counties 
on  the  north  and  west,  the  drift  is  covered  with  a  pebbleless  silt  several  feet 
in  depth.  On  the  hills  and  ridges  this  is  less  compact  than  the  white  clay 
in  districts  to  the  north,  and  the  lowland  tracts  also  have  usually  a  more 
porous  silt  than  the  typical  white  clay. 

The  glacial  di-ift  consists  mainly  of  a  brown  till,  but  where  it  reaches 
a  dejDth  of  30  feet  a  blue  till  is  usually  found  at  bottom.  The  wells  are 
often  sunk  into  the  rock  a  short  distance,  and  few  strong  wells  were  found 
which  obtain  a  supply  from  the  drift.     Their  depth  seldom  exceeds  40  feet. 

INDIVIDUAL    AVELLS. 

At  Texas  City,  in  the  northeast  part  of  the  county,  a  well  sunk  by 
T.  W.  Overton  reached  a  depth  of  302  feet.  Water  rises  within  8  feet  of 
the  sui'face.  An  inflammable  gas  was  struck  at  about  240  feet,  which  is 
estimated  to  have  a  pressure  of  75  pounds  to  the  square  inch. 

At  Eldorado  wells  enter  rock  at  about  20  feet  after  penetrating  a  few 
feet  of  surface  silt  and  a  shghtly  pebbly  clay.  "Water  is  usually  obtained 
within  30  or  40  feet.  A  well  at  Louis  Pettinger's,  2  miles  east  of  Eldo- 
rad(j,  on  a  low  drift  knoll,  reached  a  depth  of  46  feet  without  entering  rock. 
The  lower  part  was  through  a  blue  clay,  probabl}'  till.  A  well  made  by 
D.  Westbrook,  on  a  low  drift  knoll  2  miles  northeast  of  Eldorado,  reached 
a  depth  of  40  feet  without  entering  rock,  and  a  similar  depth  was  reached 
on  a  knoll  1  mile  north  of  Eldorado  in  a  well  made  by  L.  Lyson.  These 
knolls  stand  only  10  to  20  feet  above  the  bordering  plane  tracts. 

In  the  vicinity  of  Raleigh  the  shallower  wells  obtain  water  in  ih-ift, 
but  a  few  wells  have  been  sunk  into  rock,  which  is  entered  at  about  30 
feet.  In  the  })ortion  of  the  county  west  from  the  meridian  of  Raleigh 
there  are  numerous  low  hills  with  rock  nuclei,  and  wells  visually  enter  rock 
within  10  or  15  feet  of  the  surface.  These  conditions  continue  southward 
past  HamsVjurg  to  the  elevated  ridge  on  the  border  t»f  the  ct)imty.  On 
this  ridge  the  residents  depend  largely  upon  cisterns  and  springs. 


WELLS  OF  GALLATIN  COUNTY,  ILLINOIS  783 

GALLATIN   COUNTY. 
GENERAL    STATEMENT. 

Gallatin  County  is  situated  on  the  soxitheast  border  of  the  State,  a 
portion  of  its  east  boundary  being-  the  Wabash  and  a  portion  the  Ohio 
River.  It  has  an  area  of  349  square  miles,  with  Shawneetown  as  the  county 
seat.  The  eastern  third  of  the  county  is  so  low  as  to  be  extensively 
covered  with  the  sands  brought  down  by  the  Wabash  and  Ohio  rivers. 
The  northwestern  portion  Avhich  is  drained  b}^  the  north  fork  of  Saline 
Eiver  is  largely  a  low  district  only  10  to  20  feet  higher  than  the  Wabash 
and  Ohio  bottoms.  There  are,  however,  a  few  hills  with  rocky  nuclei 
which,  rise  to  a  height  of  50  feet  or  more  above  the  bordering  lowlands. 
The  southwest  corner  of  the  county  is  occupied  by  a  high  and  hilly 
unglaciated  tract,  the  continuation  of  that  noted  in  southern  Saline  County. 
There  is  a  group  of  hills  near  Shawneetown  Avliich  stand  100  to  150  feet 
above  the  Ohio  River  that  are  entu-ely  surrounded  by  the  low  bottoms  of 
the  Wabash  and  Ohio  rivers. 

With  the  exception  of  the  hilly  district  in  the  southwest  part  of  the 
county  and  the  group  of  hills  near  Shawneetown,  just  noted,  the  county  is 
covered  with  glacial  or  alluvial  deposits.  It  is  probable  that  the  glacial 
boundary  lies  a  few  miles  west  of  the  Ohio  and  Wabash  rivers,  except  at 
the  extreme  north  border  of  the  county,  where  it  apparently  crosses  the 
Wabash.  The  drift  on  the  lowlands  bordering  the  Wabash  and  Ohio  bot- 
toms is  mainly  sand,  and  it  is  difficult  to  determine  whether  it  is  of  dii-ect 
glacial  deposition.  There  are  in  places  low  knolls  and  ridges  which  are 
composed  of  sand;  they  may  be  largely  the  product  of  the  wind. 

INDIVIDUAL    WELLS. 

In  the  vicinity  of  Omaha,  in  the  northwest  part  of  the  county,  the  drift 
consists  of  a  typical  till.  Wells  on  the  low  hills  and  ridges  usually  enter 
rock  at  15  or  20  feet,  but  those  on  the  lowlands  have  penetrated  35  or  40 
feet  of  drift  without  entering  rock.  Not  infrequently  a  black  muck  is 
found  below  till  on  these  lowlands  at  a  depth  of  20  to  35  feet.  Wells  near 
the  station  in  Omaha  strike  it  at  about  35  feet,  but  farther  east  it  is  entered 
at  less  depth. 

Between  Omaha  and  Ridgway  a  well  was  driven  to  a  depth  of  98  feet 
without  reaching  rock,  mainly  through  sand.     Wells  east  and  northeast  of 


784  .  THE  ILLIiSrOIS  GLACIAL  LOBE. 

Hidg'way  are  in  several  instances  sunk  to  a  depth  of  over  50  feet,  mainly 
througli  sand.  Wells  west  and  northwest  from  this  village  are  usually 
sunlv  through  till,  and  one  well  3  miles  west  is  reported  to  have  reached  a 
depth  of  75  feet  without  entering  rock,  mainly  through  till.  A  blue  till 
was  entered  at  about  25  feet. 

Near  Cottonwood  rock  is  entered  at  only  20  feet  and  the  drift  is 
largely  sand.  Rock  is  found  at  slight  depth  between  Cottonwood  and 
New  Haven. 

At  Shawneetown  wells  usuall}^  obtain-  water  at  25  to  40  feet  in  a 
sandy  gravel  An  oil  boring  entered  rock  at  112  feet.  A  well  at  the 
fair  grounds  86  feet  in  depth  did  not  reach  the  rock. 

THE    UNGLACIATED    COUNTIES    OF    SOUTHERN    ILLINOIS. 
CiENEKAL    STATEMENT. 

There  are  seven  counties  in  the  southern  end  of  the  State — Hardin, 
Polk,  Johnson,  Union,  Alexander,  Pulaski,  and  Massac — which  are  situated 
outside  the  limits  of  the  glacial  boundary.  The  four  first  named  are  trav- 
ersed by  an  elevated  ridge,  known  as  the  "Ozark  uplift,"  which  passes 
nearly  east  to  west  from  the  Ohio  River  just  below  Shawneetown  to  the 
Mississippi  River  at  Grand  Tower.  The  crest  of  this  ridge  is  generally 
about  400  feet  above  the  Ohio  and  Mississippi  rivers,  but  occasional  knobs 
alonPT  it  reach  an  elevation  of  500  and  even  600  feet  above  the  river.  The 
most  rugged  portion  of  the  ridge  is  found  in  the  northern  6  or  8  miles  of 
these  counties  and  extends  slightlj^  into  the  counties  on  the  north — Jackson, 
Williamson,  Saline,  and  Grallatin,  as  noted  above. 

South  from  this  elevated  and  rugged  portion  of  the  ridge  there  is  a 
somewhat  hilly  tract  with  lower  altitude,  which  extends  to  the  lowlands 
covered  by  Tertiary  gravel,  which  occupy  much  of  the  three  southern  coun- 
ties of  the  State — Alexander,  Pulaski,  and  Massac. 

Although  not  covered  by  the  ice  sheet,  this  district  has  received  deposits 
of  glacial  age  which  aflPect  to  some  extent  the  condition  of  drainage  and  the 
character  of  the  soil. 

The  Ohio  and  Mississippi  valleys  have  been  filled  with  deposits  of  sand 
and  fine  gravel  to  a  depth  ]irol)ably  not  less  than  100  feet.  There  are  also 
alluvial  de})Osits  outside  the  line  of  the  present  Ohio  which  were  jji-obably 
made  at  the  time  of  the  filling  of  the  main  valleys.     A  broad  valley,  known 


WELLS  OP  SOUTHERN  ILLINOIS.  785 

as  the  Cache,  now  largely  a  cypress  swamp,  leads  westward  from  north- 
western Massac  County  across  northern  Pulaski  and  then  turns  south  into 
the  Ohio  along  the  line  of  Alexander  and  Pulaski  counties.  From  the  head 
of  this  swamp  there  is  a  well-defined  connection  with  the  Ohio  River  in 
a  low  plain  leading  southeast  to  Metropolis,  across  the  central  portion  of 
Massac  County.  This  plain  has  been  built  to  a  level  about  70  to  75  feet 
above  the  Ohio  River,  or  20  to  25  feet  above  the  highest  present  flood 
stages  of  the  stream.  Its  freshness  of  topography  is  decidedly  in  contrast 
with  that  of  the  bordering  Tertiary  formations,  in  which  there  has  been 
great  erosion.  As  noted  above  (p.  528),  this  channel  was  probably  silted 
up  either  at  the  lUinoian  or  the  lowan  stage  of  g'laciation. 

In  addition  to  the  alluvial  deposits  found  in  the  valleys  and  lowlands 
there  is  a  coating  of  loess  found  on  all  except  the  most  rugged  portions  of 
the  uplands.  This  loess  has  a  general  thickness  of  about  12  feet  on  the 
border  of  the  Ohio  and  fully  twice  that  amount  on  the  border  of  the  Mis- 
sissippi, while  in  the  interior  portions,  as  on  the  glaciated  districts  to  the 
north,  its  thickness  is  only  5  or  6  feet.  Whether  the  loess  originally  cov- 
ered the  highest  and  most  rugged  parts  of  this  ridge  is  not  known.  If 
originally  present  it  has  now  been  largely  removed.  A  more  critical  study 
may  perhaps  develop  decisive  evidence  on  this  point. 

INDIVIDUAL   WELLS. 

On  the  most  rugged  portions  of  the  ridge  there  are  very  few  residents 
and  these  depend  chiefly  upon  cistern  water.  On  the  lower  tract,  between 
the  crest  of  the  ridge  and  the  Cache,  there  is  a  limestone  district  in  which 
wells  are  usually  obtained  at  40  to  60  feet  or  less.  In  the  district  covered 
by  Tertiary  deposits  wells  are  usually  found  at  moderate  depth,  seldom 
exceeding  40  feet.  The  wells  on  the  lowland  connecting  the  Ohio  with 
the  Cache  near  Metropolis  have  in  several  instances  reached  a  depth  of 
60  to  75  feet,  but  in  the  neighborhood  of  the  Cache  they  obtain  water  at 
much  shallower  depth,  often  being  but  15  to  20  feet  deep.  Along  the  Mis- 
sissippi Valley  the  wells  are  usually  driven  to  a  depth  of  30  or  40  feet.  It 
is  reported  that  Mr.  Bolin  Sublette,  an  early  settler  in  Union  County,, 
dug  a  well  near  "Wolf  Lake  Station  to  a  depth  of  about  80  feet,  reaching  a 
level  at  least  50  feet  below  the  low  water  of  the  Mississippi  River.     It  is 

MON  XXXVIII- 50 


786  THE  ILLI^^TOIS  GLACIAL  LOBE. 

also  reported  that  a  log  was  fouud  near  the  bottom.  This  well  iudicates 
that  the  present  stream  is  flowing-  at  a  level  considerably  higher  than  the 
preglacial  rock  floor. 

At  Anna  the  wells  are  20  to  60  feet  in  depth,  the  majority  being  about 
40  feet,  and  obtain  water  in  limestone.  The  city  authorities  are  considering 
the  advisability'  of  constructing  waterworks.  The  best  wells  are  estimated 
to  have  a  capacity  of  about  100,000  gallons  a  day.  The  source  for  the 
piiblic  water  supply  naight  therefore  be  found  in  these  wells. 

At  Vienna  wells  are  ol^tained  at  25  to  60  feet  in  limestone,  tlie  usual 
depth  being  about  50  feet.  An  average  well  is  estimated  to  yield  about  12 
baiTels  of  water  a  day. 

The  village  of  Thebes  stands  in  a  portion  of  the  Mississippi  Valley 
which  is  postglacial,  and  wells  obtain  water  at  the  top  of  the  rock  at  a 
depth  of  only  20  feet.     The  residents  depend  larg-eh'  ujion  cistern  water. 

At  Cairo  the  watej-works  are  supplied  from  the  Ohio  River.  Excavated 
wells  are  not  allowed  witliin  the  city  limits.  Driven  wells  have  been  sunk 
to  depths  of  70  to  200  feet.  No  solid  rock  is  reached  at  the  latter  depth. 
The  city  engineer  reports  that  good  Avater  is  obtained  at  about  70  feet. 
The  following  section  of  a  boring  for  a  bridge,  by  the  Illinois  Central  Rail- 
road Company,  was  furnished  by  the  city  engineer.  The  surface  elevation 
is  45  feet  above  low  water  at  the  mouth  of  the  Ohio.  The  boring  therefore 
reaches  a  level  80  feet  below  the  low-water  mark: 

Section  of  boring  for  hridtie  of  lUinois  Central  Railroad  at  Cairo,  Illinois. 

Feet. 

Muil  and  sand 15 

Fine  sand 40 

Coarse  sand  and  gravel 30 

Coarse  sand,  gravel,  and  fragments  of  sand  rock 15 

Fine  sand  and  gravel 10 

Fine  wbite  sand : 15 

Total  depth 125 

This  boring  sliould  l)e  compared  with  borings  made  by  tlie  United 
States  Army  Engineers  at  ]ioiuts  between  Cairo  and  Vicksburg.' 

At  Metropolis  tlie  pulilic  water  supply  is  pumped  from  the  Ohio 
River,  but  there  are  numerous  wells  about  40  feet  in  depth.     These  wells 

•  See  reports  of  the  Chief  of  Engineers,  United  States  .\ruiy,  for  1877,  1878,  and  1879;  also 
Kei)ort  of  Mississippi  Kiver  Commission,  1881,  pp.  171-239. 


WELLS  OF  SOUTHERN  ILLINOIS.  787 

are  through  a  sUt  or  clay  for  a  few  feet  in  their  upper  portion,  but  the  greater 
part  of  the  section  is  sand.  Gravel  is  entered  near  the  bottom,  which  is 
probably  Tertiary.  As  noted  above,  wells  on  the  low  plain  leading  from 
Metropolis  northwest  to  the  Cache  are  occasionally  sunk  to  a  depth  of 
75  feet.  They  are  largelj?^  through  a  fine  sand,  but  enter  gravel  at  bottom, 
probably  Tertiary. 

At  Olmsted  wells  obtain  water  in  some  cases  at  35  feet,  but  a  Avell  on 
a  low  hill  northeast  of  the  station,  standing  140  feet  above  the  Ohio,  reached 
a  depth  of  81  feet.     The  lower  60  feet  was  entirely  a  Tertiary  gravel. 

At  Brooklyn  (Pellonia  post-office)  the  river  bank  is  about  45  feet  above 
low  water  of  the  Ohio  and  there  is  Tertiaiy  gravel  to  within  15  feet  of  the 
top.     Wells  obtain  water  in  this  gravel  near  the  river  level. 

In  the  vicinity  of  Rosebud,  in  Pope  County,  where  the  altitude  is 
nearly  260  feet  above  the  river,  there  is  a  heavy  deposit  of  Tertiary  gravel 
in  which  wells  have  occasionally  reached  a  depth  of  100  feet  without  enter- 
ing rock,  but  on  neighboring  farms  at  similar  altitude  rock  may  be  entered 
at  25  or  50  feet. 

At  Grolconda  wells  are  usually  obtained  in  the  Ohio  bottoms  at  a  depth 
of  30  to  40  feet.  A  well  made  by  Mr.  George  Boos,  at  a  level  probably 
65  feet  above  low  water  in  the  Ohio,  reached  a  depth  of  136  feet  without 
entering  rock.  The  best  water  vein  was  at  about  40  feet.  Wells  on  the 
bluff  also  reach  water  at  only  30  or  40  feet,  in  sandstone. 


CHAPTER    XV. 

SOILS. 

SOURCES   OF   SOir,  MATERIAL. 

The  principal  sources  from  which  the  soils  of  the  region  under  discus- 
sion are  derived  are  the  glacial  drift  and  the  loess,  with  its  associated  silts 
of  glacial  age.  The  underlying  rocks  are  indirectly  a  source  of  much 
material,  since  their  decomposed  surface  ^lortions  were  incorporated  in  the 
di-ift,  but  they  constitute  a  minor  source  so  far  as  direct  contribution  is  con- 
cerned. Lakes  and  streams  attending  the  melting  of  the  ice  sheet  have 
deposited  material  in  considerable  amount,  and  it  is  thought  that  the  wind 
also  has  been  influential  in  distributing-  fine  material  over  portions  of  the 
surface  of  the  region.  The  present  streams  are  also  a  source  for  soil  in  the 
districts  over  which  they  spread  in  their  flood  stages.  . 

The  preceding  discussion  has  shown  that  portions  of  the  surface  of  this 
region  date  from  the  lowan  stage  of  glaciation,  namely,  the  portions  cov- 
ered by  the  lowan  loess  and  associated  silts,  and  the  portion  in  which  the 
lowan  till  sheet  forms  the  surface.  These  deposits  form  the  surface  of  con- 
siderably more  than  one-half  the  region.  In  the  remainder  of  the  region 
the  Wisconsin  drift  constitutes  the  main  part  of  the  surface,  though  small 
areas  have  been  occupied  by  lakes  and  streams  since  the  withdrawal  of  the 
Wisconsin  ice  sheet.  The  area  covered  by  Lake  Chicago  is  the  most  con- 
spicuous illustration. 

CLASSES   OF  SOIL. 

Inasmuch  as  soils  are  largely  comjDosed  of  fragments  of  rock  material, 
they  are  naturally  dependent  to  a  certain  degree  upon  the  character  of  the 
rock  from  which  they  are  chiefly  derived.  This  is  especially  true  in  ungla- 
ciated  regions,  but  in  glaciated  regions  also  the  soil  is  found  to  depend  upon 
the  character  of  the  underlying  deposits.  There  are  several  modes  of  classi- 
fication in  use,  based  usually  upon  either  chemical  constitution  or  physical 
texture  or  characteristics.  The  classification  which  seems  to  best  serve  our 
purpose  is  based  mainly  upon  physical  characteristics.  This  classification 
also  sets  fortli  what  appear  to  be  the  characteristics  of  chief  importance. 
The  elaborate  investigations  made  by  Prof  Milton  Whitney,  of  the  United 

788 


SOILS  OF  ILLINOIS.  789 

States  Department  of  Agriculture,  on  the  Mar3^1and  soils  indicate  that  the 
texture  and  physical  conditions  of  the  soils  are  of  even  more  importance 
than  the  chemical  composition.  On  this  matter  Professor  Whitney  has 
written  as  follows:^ 

The  prevailing  ideas  of  plant  nutrition  bave  been  based  mainly  upon  the  chemical 
coiiiijositioii  of  soils.  When  it  was  found  that  the  chemical  composition  of  a  soil  and 
plant  did  not  show  what  was  lacking  in  the  soil  for  a  large  crop,  it  was  held  that  only 
a  small  iiart  of  the  plant  food  in  the  soil  is  at  any  one  time  in  a  form  of  combination 
which  is  available  to  plants;  that  the  available  plant  food  never  accumulates  as  such 
in  the  soil,  but  quickly  reverts  to  more  insoluble  forms,  which  are  unavailable  to 
plants.  Accordiug  to  this  idea  the  exhaustion  of  soils  by  continued  cropping  is  due 
to  the  actual  loss  of  available  plant  food  removed  by  the  crop  or  converted  into  an 
unavailable  form  by  chemical  changes  in  the  soil.  The  chief  use  of  fertilizers  is  to 
supply  the  plant  with  food  which  the  soil  fails  to  furnish.  The  reason  certain  plants 
do  better  ou  certain  kinds  of  soil  is  assumed  to  be  due  to  the  fact  that  plants  vary 
greatly  in  their  powers  of  gathering  their  food  from  the  soil  and  air,  and  that  thus  a 
rye  plant  would  do  well  on  a  soil  too  poor  to  give  a  good  yield  of  wheat. 

Our  investigations  on  the  Maryland  soils  seem  to  show,  however,  that  the 
texture  and  the  physical  conditions  of  the  soil  are  of  more  importance  than  the 
chemical  composition.  It  appears  that  under  favorable  conditions  of  moisture  and 
temperature  plants  can  readily  gather  sufficient  food  material  from  nearly  all  soils; 
but  if  these  conditions  of  moisture  and  heat  are  changed,  the  development  of  the 
plant  will  be  greatly  changed  and  it  will  take  up  more  or  less  food  Irom  the  soil. 
Soils  differ  greatly  in  their  texture — that  is,  in  the  amount  of  sand  and  clay  which 
they  contain — and,  as  we  have  seen,  this  controls  very  largely  the  supply  of  moisture 
which  they  can  maintain  for  the  crop  with  a  given  amount  of  rainfall.  If  there  are 
4  inches  of  rainfall  a  month,  the  coarse  sandy  soil  will  allow  most  of  this  to  run 
through  very  quickly,  so  that  there  may  not  be  more  than  5  or  G  per  cent  of  water 
held  in  the  soil  for  the  crop,  or,  say,  about  100  tons  of  water  per  acre  1  foot  deep;  and 
when  this  water  is  used  up,  the  soil  has  comparatively  little  power  to  draw  up  more 
water  from  below  for  the  use  of  the  crops.  With  a  compact  clay  soil,  on  the  other 
hand,  the  water  passes  downward  very  slowly,  and  the  soil  will  maintain  about  18  or 
20  per  cent  of  its  weight  of  water  for  the  crop,  or  about  100  or  500  tons  of  water  per 
acre  1  foot  deep.  In  the  dry  season,  also,  the  clay  soil  has  more  power  of  drawing  up 
water  from  below  and  maintaining  this  supply.  If  a  florist  should  give  a  plant  four 
times  as  much  water  as  he  gives  another  plant  of  the  same  kind,  the  two  plants  would 
develop  very  differently,  and  he  uses  this  constantly  to  produce  any  kind  of  develop- 
ment he  desires.  If  it  is  desired  to  have  the  plant  flower  or  fruit,  the  soil  is  kept 
rather  dry  and  cool.  If  it  is  desired  to  i)roduce  large  leafy  plants,  the  soil  is  kept 
much  wetter  and  warmer.  To  have  equal  success  with  different  kinds  of  plants  the 
amount  of  water  must  be  carefully  regulated  according  to  the  needs  of  the  plant. 
Some  plants  require  a  mucli  more  abundant  sui)ply  of  water  than  others.  This  con- 
trol of  moisture  and  temperature  is  far  more  important  than  the  mere  chemical  com- 
position of  the  soil. 

'  Kept.  Illinois  Board  of  WorlcTs  Fair  Coramissioners,  1893,  pp.  94-96. 


790 


THE  ILLINOIS  GLACIAL  LOBE. 


The  texture  of  our  various  soils  being  diflereut,  they  are  enabled  to  maintain  a 
variety  of  conditions  of  moisture,  and  they  partake  somewhat  of  these  artificial  con- 
ditions in  a  greenhouse,  the  conditions  in  each  of  the  soils  being  best  suited  to  the 
needs  of  certain  classes  of  plants. 

The  amount  of  moisture  which  a  soil  can  maintain  for  a  crop,  under  given  cli- 
matic conditions,  will  depend  mainly,  (1)  upon  the  amount  of  space  in  the  soil  in 
which  water  can  enter;  (2)  upon  the  extent  of  subdivision  of  this  space — that  is, 
upon  the  number  of  grains  of  sand  and  clay  there  is  in  a  given  volume  of  soil;  (3) 
upon  the  arrangement  of  these  grains,  for,  as  already  remarked,  if  the  grains  are 
symmetrically  arranged,  so  that  the  spaces  shall  all  be  of  uniform  size,  water  will 
move  through  the  soil  much  slower  than  if  the  spaces  are  of  very  unequal  sizes; 
(4)  upon  the  amount  and  condition  of  the  organic  matter  in  the  soils.  The  grains  of 
clay  are  so  exceedingly  small  that  their  number  vastly  exceeds  the  number  of  the 
grains  of  sand  and  silt,  so  that  the  percentage  of  clay  practically  determines  the 
extent  of  subdivision  of  the  space,  and  it  is  thus  the  most  important  ingredient  of 
the  soil. 

Ill  Illinois  and  adjacent  districts  the  following-  classes  of  soil  are  repre- 
sented: (1)  residuary  soils,  or  soils  formed  from  the  underlying  rock;  (2) 
stony,  or  glacial  clays;  (3)  gravelly  soils;  (4)  sandy  soils;  (5)  loess,  or 
silt  rapidly  pervious  to  water;  (6)  silt  slowly  pervious  to  water;  (7)  fine 
silts  nearly  impervious  to  water;  (8)  peaty  or  organic  material.  A  tabular 
statement  is  here  presented  which  shows  the  origin  or  mode  of  deposition 
and  the  areal  distribution  in  Illinois  of  the  several  classes  of  soil:^ 

Table  of  soils  of  Illinois. 


Variety. 

Origin  or  iiiode  of  deposition.                                       Areal  distribution. 

Eesidnary 

Decay  of  the  untlerly-  i  Driftless  portion  of  the  State  wherever  the  loess 
ing  rocks.                              as  well  as  the  glacial  drift  is  absent. 

Glacial ;  Mainly  in  the  northeastern  quarter  of  the  State, 

where  loess  and  silts  are  generally  absent.     The 
]       Shelbyville  moriiine  forms  tlie  southern  liound- 
ary  and   chiefly  the  western   boundary,  but  in 
niirtherii  Illinois  glacial  clays  form  the  soil  on 
the  lowau   drift  area  between  the  Shelbyville 
moraine  and  the  loess  of  the  Mississippi  Valley. 

(iravi-llv 

streams,  lakes. 

the  State,  and  along  strciims  leading  away  from 
tlic  Shelbyville  and  later  moraines.     This  variety 
of  soil   includes  gravel  knolls  and  ridges,  over 
wash  gravel  jilaius,  terraces,  and  beaches. 

'  This  table  wjis  published  by  the  writer  in  the  Report  of  Illinois  Board  of  World'.s  I'air  Com- 
missioners, 1895. 


SOILS  OF  ILLINOIS. 

Table  of  soils  of  Illinois — Con  tinned. 


791 


"Variety, 


Sandy . 


Origin  or  mode  of  depositien. 


Areal  distribution. 


Glacial     drainage, 
streams,  lakes,  winds. 


Mainly  in  basins  along  the  Kankakee,  Green,  and 
lower  Illinois  rivers ;  old  lake  bottom  and  raised 
beaches  near  Chicago;  also  on  bottom  lands, 
and  fringing'  in  many  places  the  low  blnflFs  of 
streams,  and  locally  developed  on  areas  of  gla- 
cial formations. 


Silts  pervious  to  water  In  part  by  slowly  flow- 
(chiefly  the  typical  ing  waters ;  probably 
loess).  in  part  by  wind. 


Along  the  Mississippi,  lower  Illinois,  lower  Wa- 
bash, and  lower  Ohio  rivers ;  also  between  the 
Illinois  and  the  Mississippi  from  the  Green  River 
Basin  south  to  the  latitude  of  Peoria,  and  in  the 
basin  of  the  Big  Bureau  Creek,  in  Bureau 
County. 


Silts  slowly  pervious  to     In  part  by  slowly  ilow- 
water.  ing  waters ;  probably 

in  part  by  wind. 


Mainly  in  west-central  Illinois,  west  of  a  line  con- 
necting Alton,  Litchfield,  Pana,  Decatur,  and 
Peoria;  also  on  the  eastern  border  of  the  Mis- 
sissippi Valley  loess  belt,  in  the  northern  part 
of  the  State. 


Silts  nearly  impervious 
to  water.  (Two  kinds, 
namely,  white  clays 
and  gumbo  ) 


Nearly  still  waters;  per- 
haps wind  in  part. 


White  clays  cover  much  of  southern  Illinois  south 
of  the  Shelbyvilie  moraine,  as  far  west  as  the 
Mississippi  loess,  east  to  the  Wabash  loess  and 
south  to  the  Ohio  River  loess.  Gumbo  is  found 
on  soms  bottom  lands  along  the  main  rivers. 


Peatyand  marly '  Vegetal   accumulations 

and  shell  deposits. 


Locally  over  the  greater  part  of  the  State  wher- 
ever drainage  is  imperfect.  Peat  is  rare  south 
of  the  latitude  of  Springfield,  but  it  abounds  in 
the  northeastern  quarter  of  the  State,  in  bogs. 
Marl  deposits  are  less  extensive  than  peat,  but 
are  fully  as  widespread. 


RBSIDTJAET  SOILS. 

The  residuary  soils  show  variations  which  correspond  in  a  rude  way 
with  variations  in  the  structure  of  the  rocks  from  which  they  are  derived, 
there  being  in  regions  underlain  by  shale  or  limestone  a  more  compact  and 
adhesive  soil  than  in  sandstone  regions.  Each  class  of  limestone  has  its 
own  peculiar  soil,  and  soils  derived  from  shales  range  from  stiif  clay  to  a 
sandy  material.  A  complete  analysis  of  the  nature  of  the  differences  dis- 
played by  the  several  classes  of  residuary  soils  has  not  been  made.  With 
proper  rotation  of  crops  these  soils  are  usually  fertile,  but  otherwise  they 
become  exhausted  sooner  than  soils  formed  on  glacial  drift. 


792  THE  ILLINOIS  GLACIAL  LOBE. 

BOWLDEK-CLAT    SOILS. 

The  soils  formed  on  tlie  bowlder  clay  are  usually  very  productive, 

being  composed  of  a  varied  rock  material,  a  large  percentage  of  which  is 

in  a  sufficiently  fine  state  of  division  to  be  available  for  plant  food.     Several 

mechanical  analyses  of  this  class  of  soil  were  made  under  the  direction  of 

Prof  Milton  Whitney,  the  results  of  which  are  given  on  a  preceding  page 

(p.  163).     Professor  Whitney  has  made  the  following  statements  regarding 

the  bowlder-clay  soils  of  Illinois:' 

The  texture  of  the  bowlder-clay  lauds,  as  shown  by  mechanical  analysis,  corre- 
sponds very  closely  with  the  wheat  and  grass  lands  of  Maryland,  although  none  of  the 
samples  are  so  rich  in  clay  as  the  limestone  soils  of  that  State.  There  is  this  to  be 
considered,  however,  that  there  is  a  larger  amount  of  volatile  matter  in  the  Illinois 
soils,  showing  that  they  contain  probablj^  twice  as  much  organic  matter  as  the  Mary- 
land soils.  This  would  tend  to  make  them  more  productive  than  soils  otherwise 
similar  in  texture. 

As  to  the  actual  tests  of  the  bowlder-clay  soils  it  may  be  said  tliat,  in 
general,  all  classes  of  grains  and  fruits  suitable  to  the  latitude  will  flourish; 
especially  where  the  surface  is  rolling  or  well  drained.  On  the  flat  tracts 
corn  and  g-rass  are  exceptionally  productive. 

GRAVELLY    SOILS. 

Grravelly  soils  are  varied  in  their  method  of  deposition,  occurring  in 
lake  beaches  and  along  streams,  in  drift  knolls  and  ridges,  and  beneath 
plains  not  now  occupied  by  sti-eams.  In  the  last-named  situation  the  plains 
are  usually  so  related  to  the  drift  ridges  as  to  show  that  the_y  were  occupied 
bv  glacial  waters.  The  beaches  have  generally  a  poor  soil,  but  the  gravel 
terraces  along  streams,  especially  those  of  glacial  age,  have  as  a  rule  a 
capping  of  loam  several  feet  thick,  which  renders  them  productive.  The 
same  is  often  true  of  gravelly  knolls  and  ridges.  On  the  whole  the  soils 
underlain  by  gravel  possess  more  fertility  than  do  sandy  soils.  This  supe- 
riority is,  however,  due  to  the  capping  of  loam  which  constitutes  the  soil, 
or,  as  in  the  drift  knolls  and  ridges,  to  an  admixture  of  clay  or  earthy 
material  witli  the  surface  portion  of  the  gravel.  The  coarse  fragments  in 
the  gravel  can  furnish  but  little  sustenance  to  crops,  although,  by  weathering, 
the  stones  may  yield  rich  material  to  the  soils  and  furnish  a  greater  variety 
of.  plant  food  than  could  be  obtained  from  siliceous  sand. 


Report  (if  lIliiHiis  lioaid  of  World's  Fair  Coiiimissionors,  p.  100. 


SOILS  OF  ILLINOIS.  793 


SANDY   SOILS. 


The  sandy  soils,  though  apparently  much  alike  in  structure,  are  varied 
in  their  methods  of  deposit.  They  occur  in  the  beaches  along  the  bor- 
ders of  Lake  Michigan,  in  the  valley  bottoms  of  the  main  streams,  on 
the  bluffs  and  along  the  borders  of  the  streams  which  lead  away  from 
the  newer  drift  district,  in  basins  within  the  newer  drift  district,  (as  the 
Kankakee  and  Illinois- Vermilion),  and  to  a  limited  extent  in  the  moraines. 
There  is  also  an  extensive  development  of  sand  in  northwestern  Illinois,  in 
the  Green  River  Basin  and  the  bordering  districts,  as  far  north  as  northern 
Whiteside  County.  Where  the  sand  is  of  medium  to  coarse  grade  it  is 
usually  rather  barren,  but  where  fine,  as  in  the  eastern  portion  of  the  sandy 
belt  bordering  the  Illinois  in  Tazewell  and  Mason  counties,  it  is  productive. 
Within  the  sand-covered  districts  there  are  more  or  less  extensive  tracts  of 
wet,  mucky  land  between  sand  ridges.  This,  where  artificially  di-ained, 
has  often  proA^ed  very  productiA^e.  There  are  districts  where  the  loess 
assumes  a.  sandy  phase,  but  in  these  places  the  sand  is  very  fine,  so  fine 
that  individual  grains  can  scarcely  be  detected  by  the  eye,  and  the  feitility 
Is  about  as  great  as  in  the  typical  loess. 


BLUFF   LOESS   SOILS. 


The  very  porous  phase  of  the  loess  within  the  region  under  discussion 
is  confined  mainly  to  the  borders  of  the  Mississippi,  Illinois,  Ohio,  and 
Wabash  rivers,  extending  back  usually  but  a  few  miles  from  the  streams. 
It  may  therefore  properly  be  called  the  "bluff  loess."  There  is,  however, 
a  porous  loess  along  the  south  border  of  the  Green  River  Basin,  and  in 
general  the  loess  between  the  Mississippi  and  Illinois  rivers  is  more  porous 
than  on  uplands  to  the  west  or  east.  In  southern  Illinois  the  loess  becomes 
a  compact  white  clay  within  a  few  miles  back  from  the  Mississippi,  Ohio, 
and  Wabash  rivers,  but  in  western  Illinois  it  changes  to  the  slowly  per- 
vious silt  which  is  more  productive  than  the  white  clay.  The  very  porous 
loess  which  borders  the  main  streams  will  permit  roots  to  penetrate  readily 
to  a  great  depth,  there  being  observations  of  penetration  to  25  or  30  feet. 
It  is,  however,  usually  of  such  a  texture  that  water  rises  in  it  by  capil- 
larity in  dry  seasons  and  adequately  supplies  the  crops. 

The  mechanical  analyses  of  specimens  of  the  bluff  loess  made  under 
the  direction  of  Professor  Whitne)^  have  been  presented  in  tabular  form  in 


794  THE  ILLINOIS  GLACIAL  LOBE. 

connection  with  the   discussion  of  the  loess  (p.   KU).     Concerning-  these 
samples  Professor  Whitney  remarks:^  , 

Tliey  are  lighter  in  texture  than  the  best  wheat  lands  of  Maryland,  although 
they  have  rather  more  organic  matter  to  balance  the  low  percentage  of  clay.  They 
are  more  like  our  fruit  and  tobacco  lands,  although  the  higher  percentage  of  volatile 
matters  indicate  that  they  are  rather  more  retentive  of  moisture. 

The  loess  differs  markedly  from  the  agricultural  lands  of  Maryland  in 
the  relative  amounts  of  clay  in  the  soil  and  subsoil.  It  is  the  rule  of  the 
Maryland  agricultural  lands  to  present  a  larger  amount  of  clay  in  the  sub- 
soil than  in  the  soil,  but  in  the  loess  the  reverse  appears  to  be  the  case,  as 
the  following  table  indicates: 

Percentage  of  clay  in  noil  and  subsoil  of  Illinois  loess. 


Soil  (per  cent  j    Subsoil  (per 
Locality.  of  clay).        I  cent  of  clay). 


Virginia  City,  No.  1 - :  15.34 

Virginia  City,  No.  2 15-15 

Carrollton - 23. 65 

Eoclc  Island ,  12-08 


Gladstone  . 


6.75 

7.10 

12.52 


8.31 


The  bluff  loess  vields  fair  crops  of  all  kinds,  but  is  especially  valuable 
for  fruit,  both  orchard  and  small  fruits.  Its  superiority  in  fertility  over  the 
white  clav^  and  finer  silts  seems  due  to  the  physical  condition  of  porosity. 
Nothing  has  been  found  to  indicate  that  it  contains  a  better  supply  of  plant 
food.  ]\Ioreover,  the  fertility  of  the  latter  is  made  certain  by  the  rich 
growth  of  such  crops  as  will  flourish  in  a  compact  soil. 

SILTS    SLOWLY    PERVIOUS    TO    WATER. 

The  silts  slowh-  pervious  to  water  embrace  the  rich  black  soil  district 
()f  the  western  portion  of  Illinois.  The  southern  boundary  lies  near  a 
line  connecting  Alton,  Litchtield,  and  Pana.  The  eastern  boundary  of 
the  main  district  may  be  })laced  at  the  border  of  the  newer  or  \Msconsin 
drift.  The  northern  boundary  is  near  the  south  border  of  the  Green  River 
Basin,  while  the  western  lioundary  is  found  in  the  loess  that  borders  the 
Mississippi.     Through  this   district   there  passes  the  belt   of   i)orous  loess 


I  Report  of  Illinois  r.o.ird  of  Worlds  F;iir  Coinraissioners,  p.  101. 


SOILS  OF  ILLINOIS.  795 

which  borders  the  Ilhnois,  a  belt  several  miles  in  width.  Aside  from  this 
main  district,  there  is  considerable  silt  of  this  class  between  the  Rock  and 
Mississippi  rivers,  in  northern  Illinois,  capping  the  earlier  or  Illinoiau  drift 
sheet. 

On  the  newer  (Wisconsin)  drift,  as  stated  above,  silts  slowly  pervious 
to  water  cover  large  districts  in  central  and  eastern  Illinois  to  a  depth  of 
several  feet.  In  northeastern  Illinois  such  a  silt  capping  is  not  a  common 
feature. 

Wherever  silts  of  this  class  (iccur  the  vegetation  is  usually  prairie 
grass,  and  there  is  a  blackening  of  the  soil  hj  humus  to  a  depth  of  several 
inches,  often  2  feet  or  more.  This  class  of  silts  affords  a  highly  productive 
soil,  one  which  will  yield  fair  returns  even  under  most  careless  methods  of 
farming.  Corn  and  grass  are  the  staple  products,  but  other  crops  have  a 
fair  yield. 

FINE    SILTS   NEARLY   IMPERVIOUS    TO    WATER. 

The  fine  silts  nearly  impervious  to  water  are  of  two  classes — white 
clay  and  "gumbo."  The  first  class  covers  the  uplands  of  much  of  southern 
Illinois.  The  second  is  common  in  portions  of  modern  river  valleys,  remote 
from  the  current  and  subject  to  o^^erflow  only  in  periods  of  extreme  high 
water,  and  has  great  extent  along  the  Illinois  and  Mississippi  river  bottoms. 
A  less  compact  silt,  found  in  river  bottoms,  is  known  as  potato  land. 

The  white  clay  is  a  pale-colored  deposit,  scarcely  at  all  blackened  by 
humus.  It  covers  the  greater  part  of  Illinois  south  from  a  line  running- 
eastward  from  Litchfield,  Illinois,  to  the  Wabash  Valley,  near  Terre  Haute, 
Indiana.  It  also  covers  much  of  Clay,  Vigo,  and  Sullivan  counties,  Indiana. 
It  is  so  poorly  drained  that  much  of  the  water  stands  on  the  surface  until 
removed  by  evaporation,  while  in  seasons  of  drought  scarcely  enough  wafer 
rises  from  below  to  supply  the  loss  from  evaporation.  In  the  southeastern 
portion  of  Illinois  and  southwestern  part  of  Indiana  there  is,  however,  a 
looser  soil,  less  easily  influenced  either  by  excess  or  deficiency  of  rainfall. 
In  those  districts  the  surface  is  hilly  and  the  white  clay  is  much  more  eroded 
than  in  flat  tracts.  The  drift  is  so  thin,  also,  that  the  rock,  in  many  places, 
comes  sufficiently  near  the  surface  to  have  become  uncovered  by  erosion 
and  thus  to  give  character  to  the  soil. 

There  are  extensive  districts  in  south-central  Illinois  with  very  flat  sur- 
face where  the  white  clay  soil  is  underlain  at  a  depth  of  a  few  inches  hj  a 


796  THE  ILLINOIS  GLACIAL  LOBE. 

ferruginous  crust  or  ocliery  clay,  which  is  exceedingly  refractory,  g'iving 
very  slow  access  to  air  or  water.  With  this  exception,  however,  the  crust 
is  either  absent  or  is  so  low  down  that  it  does  not  seriously  aflfect  the  soil. 
Aside  from  corn,  which  is  liable  to  be  injured  by  autunni  droughts,  the  lead- 
ing crops  of  the  State  do  fairly  well.  Wheat  yields  as  well  as  anywhere  in 
the  State,  wliile  orchards  and  small  fruits  bring  very  })rofitable  returns.  The 
soil  needs  careful  attention,  but  there  is  every  indication  that  where  properly 
cared  for  it  will  become  as  profitable  for  agriculture  as  the  soils  which  now 
enjoy  a  better  reputation. 

Concerning  the  analvses  of  the  samples  of  white  clay  and  also  of  the 
more  porous  upland  loess  (see  \).  162)  Professor  Whitney  remarks:^ 

Of  the  upland  loess  there  are  two  types — those  which  are  pervious  to  water  and 
which  are  valuable  agricultural  lauds;  those  which  are  comj)act  and  almost  imper- 
vious to  water,  locally  known  as  white  clays,  which  are  so  very  retentive  of  moisture 
as  to  be  always  wet  and  of  less  agricultural  value.  The  mechanical  analysis  shows 
that  these  two  types  of  land  are  almost  identical  in  texture,  and  that  the  white  clays 
(1321,  1342,  1343,  and  1345)  have  no  more  clay  than  the  other  samples  of  upland 
loess,  which  are  considered  very  fertile  lauds.  The  wetness  of  these  white  clay  lands, 
therefore,  is  not  due  to  the  fact  that  they  contain  more  clay,  but  it  must  be  ascribed 
to  some  other  cause.  They  contain  no  more  organic  matter,  so  that  it  can  not  be  due 
to  an  excessive  amount  of  this  material.  It  must  be  due,  therefore,  to  one  of  two 
causes — either  that  there  is  a  hard  pan  or  a  layer  of  impervious  clay  underlying  these 
lands  which  retards  the  descent  of  the  water  and  prevents  the  excess  of  raiufall  being 
carried  down,  or  it  may  be  due  to  a  diiierence  in  the  arrangement  in  the  grains.  Our 
laboratory  experiments  do  not  seem  to  indicate  that  there  is  any  material  difference 
in  the  arrangement  of  the  grains  in  these  two  classes  of  soils,  but  this  can  only  be 
determined  with  certainty  by  investigation  of  the  soils  in  their  natural  position  in  the 
field.  If  the  pervious  character  of  the  white  clays  is  due  to  a  difference  in  the  arrange- 
ment of  the  grains,  the  lands  ought  to  be  underdraiued  so  that  the  excess  o(  water 
may  be  artificially  removed,  or  the  trouble  may  be  greatly  alleviated  by  liming  the  land, 
which  will  tend  to  make  it  more  loamy  and  less  retentive  of  moisture.  The  effect  of 
kainit  and  of  some  of  the  jjhosphates  would  probably  have  a  similar  effect  on  the  land 
if  applied  regularly  for  a  number  of  years.  If  the  soils  are  impervious  because  of  a 
hard  pan  or  a  layer  of  impervious  clay  3  or  4  feet  below  the  surface,  then  fertilizers  will 
do  very  little  to  correct  the  evil  unless  the  lands  are  systematically  luiderdrained. 

VBATY   AND   OBOANIC   SOILS. 

The  })eat>'  and  organic  soils  occur  in  basins  or  in  poorly  drained 
tracts  where  rank  vegetation  becomes  submerged  at  certain  seasons  and  is 
thus  prevented  from  atmospheric  decay.     This  class  of  soils  is  much  more 


'  Keiiorli  1)1'  Illinois  Hoard  of  World's  Fair  Commissioners,  pii.  Ull-102 


SOILS  OF  ILLINOIS.  797 

abundant  in  the  northern  part  of  tlie  region  than  the  southern.  Peat  bogs 
occur,  however,  south  of  the  center  of  the  State  of  Illinois. 

Manv  bogs  are  underlain  by  shell  marl  as  well  as  by  peat.  The  marl 
is  seldom  suflficieiatly  pure  or  abundant  to  be  used  in  the  manufacture  of 
lime.  The  marl  beds  are  especially  abundant  on  the  south  and  east  borders 
of  Lake  Michigan 

In  many  instances  the  bogs  when  drained,  the  peat  })eing  given  time 
to  ripen  and  become  warm,  yield  large  crops  of  potatoes  and  other  garden 
truck.  Wheat  or  other  crops  requiring  mineral  food  in  the  ripening  of 
tbeir  grains  can  scarcely  be  expected  to  grow  on  such  soil  until  it  becomes 
charged  with  earthy  material  by  natural  or  artificial  processes. 


INDEX. 


^5l.  Page. 

Abingdon,  111.,  "wella  at .* 678 

Adair,  111.,  wrll  at G86 

Adams  County,  111.,  altitude  of 10 

gf  neral  features  of ll'^l]^ 

ridges  in 58-59 

section  of  well  in 59 

wells  in 713-718 

Adeline,  111.,  wells  at 605 

Adeline  or  Leaf  Kiver  esker,  altitudes  and  course  of.      76-78 

composition  of 77-78 

.^olian  loess  dei»osits 183-184 

Aftonian  soil  and  weathered  zone 20 

Albertiin  drift  sheet 20,21,22 

Albion,  111.,  well  at 776 

Alden,  111.,  well  at 576 

Alden,  W.  C.,  traces  of  Tolleston  beach  found  by 448 

Aledo,  111.,  wells  at 622 

Alexander,  111.,  wells  at 723-724 

Alexander  County,  111.,  altitude  of 11 

Algoucj uin,  III.,  wells  at 578 

Allejian,  Mich.,  sections  near 359,360 

well  at 359 

Allegan  County,  Mich.,  moraine  in 348-349 

section  of  well  in 402 

th  icliuess  of  drift  in 355 

wells  in 362,  363,  304 

Aljiha,  111.,  wells  at 625 

Alpine,  111.  wells  near 590 

Alsey,  111.,  wells  near 722 

Altii,  III.,  wells  at  and  near 207,  674-675 

Altaniont,  III.,  wells  at 753-754 

Altitudes  of  drift  surface  and  rock  floor,  table  show- 
ing         9-11 

of  Bbelbyville  moraine 194-195 

Alton,  111  ,  glacial  strife  at 86-87 

jaw  of  mastdduD  found  above 166 

loess  at 183 

wells  at 749 

Alvin.lU  .well  at 700 

Am  boy.  111.,  wells  at 610 

Analyses,  blufl'  loess 161 

bowlder  clays 163 

clays  of  Pleistocene  age 411 

Itiess 164 

upland  loess 162 

Andover,  111.,  wells  at 625 

Andrews,  Edmund,  cited  on  bar  north  of  Evanston  .  445 

cited  on  beacbes  of  Lake  Chicago 418-419 

cited  on  pockets  of  dry  sand  in  lake  tunnel 408 

cited  on  the  present  beach  of  Lake  Michigan  . . .  453 

estimates  of  extent  of  beacb  of  Lake  Michigan, 

made  by 454-456, 459 

on  the  emergence  of  Lake  Chicago 440 

Anna,  III.,  wells  at 786 


Page. 

Areola,  111.,  wells  at  and  near 222,731 

Argo,  111.,  well  at 613 

Arlington  Heights,  III.,  wells  at 587 

Artesian  wslls  in  the  Mississippi  Valley 56 

Artingstall,  Samuel  G-.,  cited  on  thickness  of  drift  in 

Chicago , 406 

drift-buried  valley  first  noted  by 583 

Apple  Creek,  watershed  of 522 

Apple  River,  effect  of  glaciation  upon 477 

Ash  Grove,  drift  sheets  at 142 

wells  near GGl 

Ashkum,  111.,  wells  near G57 

Ashland,  111.,  section  of  drift  beds  in  coal  shaft;  at..  127 
Ashley,  George  H.,  quoted  on  changes  in  Pigeon 

Creek  drainage  basin 98 

Ashley,  III.,  wells  near 770 

Ashton,  111.,  wells  at 600 

Astoria,  III.,  wells  at 688 

Atlanta,  111. ,  section  of  well  at . . . ^-  - .  206 

wells  at 707-708 

Augusta,  III.,  wells  at 683 

Aurora,  III.,  wells  at 599 

Au  Sable  Creek,  watershed  of 508 

Austin,  H.  "W".,  information  furnished  by 360 

Ava,  111.,  wells  at 780 

A  sis  of  upheaval 15 

Kailey,  Ind.,  section  of  well  at 396 

Bain,  H.  F.,  aid  by 147,  li8, 187 

cited  on  loess  deposition. 182 

cited  on  sub-Aftoniau  and  Kansan  ice  sbeets 23 

examination  of  Warsaw  exposures 04-95 

reference  to 44.46 

Baker,  M.  N.,  cited  on  sources  of  city  water  supply..  557 

Bald  Mound 299 

Bannister,  H.  M.,  cited  on  section  of  coal  shaft  at  ■ 

Bloomington,  111 108 

cited  on  southwestward  outlet  from  Lake  Michi- 
gan Basin  418 

Barringtou,  111.,  wells  at 581 

Barry,  111.,  wells  near 719 

Bartlett,  111.,  well  at 585 

Base  lines  defined 4-6 

Basseron  Creek,  course  and  drainage  of 535 

Bay  Creek,  chert  near 62 

course  of 480-481 

wells  at 64 

Baylis,  111.,  section  of  well  north  of 63 

wells  at ^ 720 

Beaches,  discussion  of  a  possible  second  emergence 

of 446-447 

Eeardstown,  111.,  altitude  of  rock  bottonx  at 500 

wells  at 711 

799 


800 


INDEX. 


Bear  Creuk,  course  of. 480 

Bejitty's  Mound,  III.,  (veils  at 747 

Beecher,  TU.,  wells  near 754 

Belleville,  III.,  wells  at 753 

Belvidere,  111.,  fossils  at 139 

wcllsat 573-574 

Benient,  111.,  wells  at 220,  704 

Benton  Harlior.ilicb..  till  riil;;o  near ;{86-387 

BevflD,  J.  S.,  inlbrmution  fuinislied  by 206 

Berksville,  111.,  wells  near 7GG 

Berrien  County,  Mich.,  altitude  of 405 

thickness  of  drift  in 355 

wells  in 373,374 

Bensonvill'e.  111.,  well  at 592 

Bethany,  111.,  depth  of  drift  at 217 

wells  at 730' 

Beverlj',  111.,  section  in  well  east  of 00 

wells  at 718 

Beyer,  S.  W.,  aid  by 187 

Biggsville,  111.. -wells  at G80 

Big  Meadow  Channel,  discussion  of 481-482 

Big  Muddy  Kiver,  wuterslied  of 526-527 

Big  Raccoon  Creek,  source  and  watershed  of 535-53G 

Big  Sandy  Creek,  watershed  of 522 

BlackinioD,  William,  well  section  of 55 

Black  Lake,  depth  of 441 

Black  River,  drainage  basiu  of 541 

Black  soil  (Yarmouth),  depth  to,  in  wells  near  Den- 
mark, Iowa 54 

Blatchley,  W.  S.,  information  furnished  hy 410 

Blooraingdale,  Ind  ,  gravel-tilled  valley  near 1238-239 

Bloouiingdale,  Mich.,  well  at 365 

Bloomington,  111.,  buried  soil  at 265 

drift  sheet  at 180 

section  of  coal  shaft  at 108 

structure  of  drift  from  Dekalb  County  to 267 

valley-like  depression  southeast  of 271 

wcllaat 694-695 

Bloomington  morainic  system,  distribution 241-243 

Gutwasliof -270-280 

range  in  altitude  of 245 

relief  of.. 244 

structure  of  the  drift  of 266-269 

thickness  of  the  drift  of 262-266 

topography  of 245-262 

Blue  Grass,  Iowa,  exposures  at 46 

"Blue  Island,"  till  ridge  known  as 382-384 

Blue  Island,  III.,  wells  at 590 

BluOiMound,  111.,  well  at 729 

Blue  Ridge,  well  at 234 

Bluff  Creek,  amount  of  cutting  along  preglacial 488 

preglacial  course  of 485 

Bolton,  111 .,  gravelly  belt  at 80 

Bonrl  County,  111.,  altitude  of 11 

general  features  uf 750 

wells  in 750-752 

Bonus  Township,  111.,  wells  in 574 

Bon  Tas  River,  watershed  of 531 

Boone  County,  111.,  altitude  of 9 

drift  in 573 

gravel  knolls  in 136 

situation  and  area  of 573 

till  ridge  in 135 

wellsin 573-575 

Ilowlders  along  Chicago  DrainatO  Caual 420 

at  Keokuk,  Iowa 95 


I'uge. 

I    IJowlders  in  Bioomingdalc  Township,  111 357 

1  in  Lee  County,  Iowa 41 

'  in  Pike  County,  III 62 

j  in  southwestern  Indiana 66 

I  near  Blue  Island,  111 383-384 

near  Burton.  Ill 59 

near  Fort  Madison.  Iowa .35-50 

near  Gilbert  .Station,  111 302 

near  Morris,  111 325-326 

near  St.  Louis,  Mo 64 

near  Torkville,  III 312 

Bowman ville.  111.,  wells  near 588 

Briar  Hill  Station.  111.,  wells  near 594 

Braceville,  111.,  wells  at G47 

Bradley,  F.  H.,  cited  on  deposits  in  Vermilion  County .  233 

cited  on  name  of  Lake  Kankakee 328 

cited  on  section  near  Newport,  Ind 236 

Braidwood,  111.,  well  at 650 

Bridgmau,  Mich.,  structure  of  drift  at 399 

thickness  of  drift  at 392 

Brighton,  111.,  wells  at 743 

Broadwell,  111. ,  wells  at 708 

Brooklyn,  111.,  wells  at 787 

Brown  County,  111.,  altitude  of 10 

general  features  of 712-713 

wells  in 712-713 

Brown  Station.  111.,  well  near 776 

Bruilletts  Creek,  outwasb  near  head  of 238 

Buckley,  111. ,  wells  at G61 

Buda,  111.,  well  at 628-629 

Buell,   Ira   M.,   cited    on    deposits   in    Winnebago 

County 109-110 

cited  on  exposures  of  stria? 87 

reference  to 88, 135. 141 

well  record  collected  by 570-572 

work  on  till  ridges  in  Winnebago  and  Boone 

counties 135 

Buffalo  Hart  moraine,  description  of 74-76 

dril"t  in 75 

Bunker  Hill,  111.,  wells  at 743 

Bnreau  County,  111.,  altitude  of 9 

bowlders  in 269 

buried  soil  in 264 

drift  structure  in 267 

general  features  of 626-027 

ridge  in 244 

table  of  deep-wellsin 630-633 

wells  in 626-633 

Bureau, Creek,  topography  near 246 

topography  of  the  drainage  basin  of 248-250 

watershed  of 512-513 

Bureau  Junction,  111.,  altitude  of  rock  bottom  at 500 

well  at 629 

Buried  rauck.*ce  Muck,  buried. 
Buried  peat,  «ce  Peat,  buried. 
Buried  silt,  Ace  Silt,  buried. 
Buried  soil,  nee  Soil,  buried. 

Burlington,  111.,  buried  soil  near 263-264 

topography  near 247-248 

wells  at 590 

Burlington,  Iowa,  fossils  found  at 169 

glacial  strite  at 85-86,105 

loess  at 156, 169, 183 

Burr.  Vu  M.,  boring  reported  by 21(4 

Burtnu,  lU.,  drift  strueture  near 59 

wells  near 717 


INDEX. 


801 


Page. 

Bushnell,  111.,  altitude  near 482 

drift  near 26 

old  river  valley  near 481-482 

wells  at 685 

Butler,  IU..well3  at  ....' 7-41 

Byron,  111.,  wells  at 606 

C. 

Cache  River,  effect  of  glaciation  on 528 

Cairo,  111.,  preglacial  drainage  near 71 

wells  at 786 

Cairo,  Iowa,  wells  near 50 

Caledonia,  III.,  wells  at 574 

Calhoan  County,  111.,  altitude  of 11, 15 

drift  border  in 35, 37 

wells  in 745-746 

Call,  R.  E.;  fossils  identified  by 168 

Calumet  or  second  beacb,  character  of 444-446 

course  of 442^44 

Calumet  River,  drainage  basin  of 538-539 

sand  deposits  near 409-410 

section  of  ridge  near 396 

structure  of  drift  along 393 

Calvin,  S.,  aid  by 147, 148, 187 

cited  on  the  ice  margin  in  Johnson  County,  Iowa.  150 
cited  on  the  lowan  and  Kansan  sheet  of  north- 
eastern Iowa,  McGee  and 139 

cited  on  the  limits  ot  lowan  drift 144 

discovery  of  glacial  striaa  by 85 

reference  to 44,  46 

Cambridge,  111.,  wells  at 624-625 

Campbell  Hill,  III.,  welU  at 779 

Campbell,  J.  T.,  information  furnished  by 412 

Camp  Point,  III.,  wells  at 716 

Campton  Township,  topograph}-- south,  of 299-300 

Campus,  III.,  wells  at :...  667 

Canton,  111.,  wells  at 687 

Carbondale,  111.,  wells  at 780 

Carbon  Hill,  III.,  wells  at 647 

Carlinville,  111.,  wells  at 743 

Carlyle,  III.,  wells  at 760 

Carmi,  111.,  wells  at 777 

Carroll  County,  III.,  altitude  of 9 

general  features  of 148,611 

wells  in 611-613 

Carroll  Creek,  gorge  near 495 

CarroUton,  111.,  wells  at 745 

Carthage,  111.,  filled  valley  near 57 

wells  at 682 

Cary,  111.,  wells  near 578 

Casey,  III.,  wells  at 734 

Cass  County,  111.,  altitude  of 10 

general  features  of 710 

wells  in 710-711 

Centralia,  111.,  wells  at 760 

Cedarville,  111.,  belt  of  gravelly  drift  near 81 

gorge  at 495 

soil  analysis  at 161 

Cerro  Gordo,  111.,  drift  at 220-221 

wells  at 704 

Cerro  Gordo  moraine,  character  of  the  outwash  of. . .  221-222 

distribution  of -. 218 

structure  of  the  drift  in 219-221 

topography  of 218-219 

Chadwick,  111.,  wells  at 613 

MON  XXXVUI 51 


Page. 

Chamberlin,  T.  C.,aid  by 127,187,327 

cited  on  artesian  wells 555 

cited  on  beaches  of  Lake  Michigan 419,438 

cited  on  classification  of  glacial  deposits 185 

cited  on  distribution  of  Illinois  moraines 2, 3 

cited  on  early  Wisconsin  drift  sheet 191 

cited  on  elevation  of  abandoned  channel  of  the 

Mississippi 93 

cited  on  erosion  of  Lake  Michigan 457 

cited  on  extent  of  Shelby ville  drift  sheet 192 

cited  on  Leaf  River  or  Adeline  esker 76 

cited  on  loess  deposition 177, 178 

cited  on  Marengo  Ridge  moraine 290 

cited  on  names  of  glacial  deposits 19, 20 

cited  on  preglacial  basin  of  Lake  Michigan 7 

cited  on  Shelby  ville  moraine 192 

cited  on  structure  of  Champaign  morainic  sys- 
tem  232 

cited  on  structure  of  Sheibyville  moraine 198 

cited  on  topography  of  Marengo  Ridge  moraine.  291 

cited  on  Valparaiso  morainic  system 339 

cited  on  Wisconsin  clay  beds 441 

examination  of  Warsaw  exposure 94-95 

glacial  work  of 3^4 

on  invasions  of  the  ice  fields 23 

on  material  in  abandoned  channel  of  the  Mis- 
sissippi        93_94 

on  topography  of  Kettle  moraine 303 

quoted  on  drift  in  Kankakee  Basin 317 

quoted  on  sand  areas  in  Kankakee  Basin 328 

reference  to 421,543,547,551 

report  on  boring  at  Lake  Koshkonong 484 

work  on  beaches 427 

work  on  sand  areas 333 

Chamberlin,  T.C.,  and  Salisbury,  R.  D.,  cited  on  the 

drift  border  in  southern  Wisconsin 43^4 

Champaign,  III.,  sections  at 234 

topography  near 227 

wells  at 702 

Champaign  County,  HI.,  altitude  of 10 

general  features  of 701 

limestone  in 232 

till  plain  in 239 

wells  in 701-703 

Champaign  morainic  system,  distribution  of 223-225 

range  in  altitude  of 226 

relief  of 225-226 

topography  of 227-231 

Chapin,  111.,  wells  at 723 

Charles  Mound,  altitude  of 8, 16 

Charleston,  III.,  wells  at 201, 735 

Chatsworth-Cayuga  Ridge,  topography  near 259-260 

Chats  worth.  III.,  wells  at 666-667 

Chebanse,  HI.,  wells  near 657 

Chemung,  111.,  wells  near 576 

Chenoa,  111.,  wells  at 693 

Chesterton,  Ind.,  analysis  of  clay  at 411 

section  of  woll  near 396 

Chicago,  altitude  of  plain  west  and  south  of 404 

structure  of  drift  at  Fullerton  avenue  in 409 

structure  of  drift  at  Hyde  Park  Township  in...  409 

stri^  on  Stony  Island  in 4i5_4i6 

thickness  of  drift  in 406 

Chicago  Drainage  Canal,  bowlders  along 426 

structure  of  the  drift  along 407 

Chicago  Heights,  III .,  wells  at 591 


802 


I]S"DEX. 


Page. 

Chicago  Ontlet,  maps  of 420-421 

meaning  of  name 420 

-width  of 424 

Chicago  River,  beacn  on  west  side  of 430 

drainage  basin  of 538 

Chillicothe,  terrace  at 275-276 

Christian  County,  111.,  altitnde  of 10 

analysis  of  soil  from 161 

general  features  of 725-726 

wells  in 725-727 

Cissna  Park,  111.,  well  at 661 

Cisne.  111.,  wells  near 775 

Clark  Conn  ty,  HI.,  altitude  of 10 

general  features  of 73^734 

wells  in 733-734 

Clay  County.  111.,  altitude  of 11 

general  features  of 757-758 

wells  in 757-758 

Clayton,  111.,  drift  sheets  in  the  vicinity  of '142 

wells  at 660-661, 705-706, 716 

Clinton,  IlL,  section  of  gas  well  at 205 

thickness  of  drift  at 205 

Clinton.  Iowa,  glacial  deposits  at 147-148 

preglacial  course  of  the  Mississippi  Kiver  below.  466-467 

Clinton  County,  111.,  altitude  of 11 

general  features  of 760 

table  of  wells  in 761 

wells  in 760-761 

Clinton  County,  Iowa,  belt  of  drift  in 144-145 

Clinton  Township  111.,  section  of  knoll  in 287 

Clyde  Township,  sandy  belt  in 149 

Coal  City,  111.,  wells  at 647 

Coal  Creek,  gravel  along 239 

Coal  Measures  district,  altitude  and  drainage  of 17 

Coatsburg,  HI.,  composition  of  ridge  leading  from.,.      61-62 

section  in  a  boring  for  coal  east  of 02 

wells  at 715-716 

Coles  County,  111.,  altitude  of 10 

general  features  of 734-735 

wells  in 217,734-730 

Coleman,  A.  P.,  cited  on  Toronto  formation 189 

Colfax,  111.,  wells  at 694 

Collett,  John,  reference  to - 88 

Cohima,  Mich .,  well  at 369 

Cols 100,101,102 

Columbia,  111.,  exposures  at 65 

wellsat    765-766 

Columbia  Station.  Mich.,  section  near 365 

Columbus  City.  Iowa,  well  at 50 

Columbus  Junction,  Iowa,  abandoned  channel  near.  90, 91, 93 

wells  at 34,50 

Conaro,  James,  well  section  of. 55 

Concord,  111.,  wells  at 777 

Cooley,  L.  E.,  cited  on  the  Chicago  outlet 419,425 

cited  on  variation  in  the  bed  of  the  upper  Illi- 
nois Kiver 502 

cited  on  the  watershed  of  Des  Plaincs  liiver 503 

the  drainage  area  of  tho  Illinois  River  estimated 

hy 497 

filling,  estimated  by -124 

information  furnished  by 384,422 

study  of  the  movement  of  water  iu  Lake  Michi- 
gan by 455-456 

Cool  Spring  jmstoflico.  ridge  near 72 

Cook  CfMiiity,  III.,  altitude  of 9 

situalion  ami  general  ff-aturoa  of 581-583 


Page. 

Cook  County,  111.,  wells  in 581-591 

Coon  Creek,  well  near 574 

Cooper,  HI.,  wells  at 692 

Copperas  Creek,  watershed  of 516 

Coppock,  Iowa,  old  channel  of  the  Mississippi  Eiver 

at 92.93 

Cordilleran,  ice  field,  extent  of 22 

Cornell,  111.,  wells  at 666 

Cortland,  topography  near 248 

Cottonwood,  HI.,  wells  near 784 

Conlterville,  111.,  wells  at 769 

Covel  Creek,  watershed  of 510-511 

Covel  Ridge,  description  of 288-289 

Covert,  wells  near 400-401 

Covert  Ridge,  altitade  of 391 

beach  near 433 

bowlders  on 393-394 

course  or 388-3S9 

sand  ridge  on 433 

.«!ection  of 394 

topography  of 380-390 

wave  action  at 436 

wells  and  borings  on , 400,401.402,403 

Cowden.IU  .wells  at 739 

Crab  Orchard  Creek,  watershed  of 527 

Crawfish  Flats,  111.,  wells  at 776 

Crawford  County,  HI.,  altitude  of 11 

general  features  of 755 

wells  in 755-756 

Crescent,  111.,  wells  near 659 

Crescent  City,  drift  sheets  at 142 

Creslon,  111.,  wells  at 608 

Crooked  Creek,  watershed  of 520 

Cropsey  Ridge,  topography  near 253-259 

Crossville,  HI.,  wells  near 777 

Crystal  Lake,  111 .,  wells  at 577-578 

Cullom.  111.,  wells  at 607 

Cumberland  County,  111.,  altitude  of 10 

exposures  of  Sangamon  soil  in 127 

general  features  of 736-737 

.soil  analysis 162 

wells  in 736-7.t7 

Gumming,  Thomas,  information,  furnished  by 647 

Curran,  HI.,  wells  at 725 

Curtis,  G.  C,  and  J.  E.  "WoodwortU  cited  on  Nan- 
tucket as  a  mttrainal  island 272 

Curtis,  L.  R.,  acknowledgments  to 641 

T>. 

Dakota,  Stephenson  County,  transported  rock  ledges 

near 83 

Dall,  W.  K.,  examination  of  fossils  by 115 

fossils  identified  by 169-170 

Dallas,  III.,  wells  at 082 

Dalton.  111.,  wells  at 730 

Dalt on  City,  wells  at 217 

Danforth,  III.,  wells  at 657-658 

Dan  vers,  III.,  wells  at 695 

Danville,  III.,  well  at 699 

Danville  Junction.  HI.,  well  at 699 

Darling,  G.  "W.,  statement  by 071 

Davenport,  Iowa,  fossils  found  at 168, 17^ 

section  in  railway  cutting  near 128 

section  of  drift  at 45 

Dnvie.s8  County.  III.,  drift  border  iu 69 

Davis,  W.  M.,  cited  on  the  Chicago  Outlet 420 


INDEX. 


803 


Page. 

Davia  Juuction,  111.,  wells  at 607 

Dawsou,  George  M.,  cited  on  centers  of  ice  dispersion .  22 

cited  on  Cordilleran  ice  field 22 

Dean,  George,  actnowledgments  to 627 

Deans  Corners,  111.,  well  at 581 

»ecatur,  111. ,  sections  of  drift  at 203-204 

wells  at 729 

Decorra,  111.,  wells  near 680 

Deer  Creek,  gravel  deposits  in 274 

Deerfield,  till  ridge  near 381 

Deerfiold  post-office,  111.,  well  at 602 

Deep  Kiver,  exposures  of  clay  near 410 

Deep  Kiver  Basin,  old  bay  near 431 

Dekalb,  111.,  wells  at 602-603 

Dekalb  County,  111.,  altitude  of 9 

bowlders  in 268 

buried  soil  in 264 

general  features  of 599-600 

structure  of  drift  from  Bloomington  to 267-268 

wells  in 599-604 

Delavan,  111.,  wells  at 691 

Denmark,  Iowa,  section  in  wells  near 54,  55 

Densmore,  J.  E. ,  wells  of 63,  64 

Deselm  poat-ofQce,  111.,  wells  at 654 

Des  Moines  County,  Iowa,  wells  in 50 

Des  Plaines  Kiver,  beacb  on  west  side  of 430 

deposits  along 376-377 

erosion  in  valley  of 422-423 

strisB  in  valley  of 415 

terraces  on 321-322 

till  ridge  near 380 

topography  along 384 

topography  near 345 

watershed  ofthe 503-505 

Des  Plaines  Village,  111.,  wells  at 587 

Detroit,  Dl.,  wells  near 720 

"Devil's  Backbone,"  description  of 286-287 

Devonian  shale 14 

Dewey,  F.  "W.,  information  furnished  by .  649 

Dewitt  County,  111.,  altitude  of 10 

general  features  of 704-705 

wells  in 704-707 

Dickey,  111.,  wells  at 654 

Dickerson,  111.,  well  near 702 

Diona,  111.,  wells  at 736 

Displacement  of  the  Mississippi,  temporary 89-97 

Dixon,  111.,  exposures  of  lowan  till  in 138 

wells  at 609 

Dowagiac  Kiver,  course  of 540 

Downers  Grove,  HI.,  wells  near 593 

Donovan,  111.,  drift  sheets  at 143 

wells  near 659 

Dooley,  P.  T.,  information  furnished  by 580 

Douglas  County,  111.,  altitude  of 10 

general  features  of 731 

wells  in 236, 731 

Drainage,  changes  in  southwestern  Indiana  in 97-104 

from  the  ice  sheet  in  the  Mississippi  "Valley 71 

influence  of  the  drift  upon 460-461 

Drentbe,  wells  at 403 

Drift,  altitude  of 9-11 

average  thickness  of 544-546 

changes  in  central  Illinois  in 28 

methods  of  estimating  thickness  of 543 

relation  of  the  Illinoian  to  the  lowan 24-25 

outline  of  and  intervals  between  sheets  of 20-21 


Page. 
1-2 
33-34 
27-28 
8-9,  27 
26-27 
64 
37-38 
34-38 
43^4 
40-63 
3&-40 
183, 188 
9-11 
12 
73, 135 
35,69 
98, 102 
160, 164 
733 
756 
757 
595 
-208,  674 


Drift,  previous  investigations  of 

sections  of  the  Illinoian 

structure  of 

thickness  of 

topography  of 

Drift  border,  character  of  east  of  the  Dlinois  Kiver. . 

determination  of  the 

distribution  of  the 

structure  of,  in  southern  "Wisconsin 

structure  of,  in  southeastern  Iowa 

topographic  character  of  the 

Driftless  area,  features  of 34, 144, 152. 153, 154. 

Drift  surface,  Illinois,  table  of  altitudes  of 

Michigan,  Indiana,  andlowa,  average  altitudeof. 

Drumlina,  occurrence  of 

Dubois  County,  Ind.,  drift  border  in 

changes  in  drainage  in 

Dubuq^ue,  Iowa,  analyses  of  soil  at 

Dudley,  111.,  wells  at 

Duncanville,  111.,  wells  near 

Dundas,  HI.,  wells  at 

Dundee,  111.,  wells  at 

Dunlap,  wells  near 207- 

Dunning,  111.,  well  near 

Dupage  County,  111.,  altitude  of 

area  and  general  features  of 

wells  in 

Dupage  Kiver,  deposits  on 

watershed  of 

Duquoin,  III.,  wells  near 

Dustin  post-office,  111.,  wells  at 

D wight.  111.,  wells  at 

Dyer,  Ind.,  beach  near 

section  of  beach  at 439 

Eagle  Lake,  welle  near 364 

Earlville,  111.,  wells  near 636 

Early  Wisconsin  drift 20 

East  Carondelet,  111.,  wells  at 762 

East  Crow  Creek,  watershed  of 513 

East  DubucLue,  Iowa,  soil  analyses  at 161 

well  at 565 

East  Lynn,  111.,  wells  at 699 

East  St.  Louis,  Dl .,  analyses  of  gumbo  at 160, 163 

drift  below 65 

wells  at 762 

Eden  Station,  111.,  wells  near 769 

Edgar  County,  111.,  altitude  of 10 

general  features  of 732 

outwash  in  northern 238 

wells  in 217,  732-733 

Edgewood,  111.,  wells  near 754 

Edwards  County,  111.,  altitude  of 11 

general  features  of 775 

wells  in 775-776 

Edwards  Kiver,  description  of  course  of 478-479 

well  near 622 

Edwardsville,  111.,  wells  at 749 

Eel  Kiver,  strise  along 414-415 

Effingham,  lU.,  wells  near 754 

Effingham  County,  111.,  altitude  of li 

general  features  of 753 

wells  in 753-754 

Eldorado,  111.,  wells  at 782 

Elida,  111.,  wells  at 572-573 


591 
591-594 
376 
505 
771 
601 
665 
431 


804 


INDEX. 


Elgin,  m.,  Trells  at  and  near 585, 

Elkhart,  III.,  wells  at 

Elkliart  Mound,  description  of 

Elkhorn  Creek  Basin 18,79, 

Elkville,  nl.,  wells  at 

EUery,  111.,  wells  near 

Elmhurst,  111.,  wells  at 

Elm  wood,  HI.,  wells  near 

Elpasn,  lU.,  wells  at 

ElvastoD,  m.,  wells  at 

Elwood,  Iowa,  drift  border  near 

Embarras  Eiver,  course  and  watershed  of 

outwashin  valley  of --■  209- 

wells  along 

Emden,  111.,  well  at 

English,  J.  G.,  well  section  reported  by 

English  Prairie  post-oifice,  wells  at 

Eolian  loess  dposits 

Erie,  111.,  wells  near 

Ester,  Haaelhnrst 

Garden  Plain 

Leaf  Kiver  or  Adeline 

Esker  ridges  of  northwestern  Illinois 

Esker  system,  Pecatouica 

Eubanks,  111.,  drift  border  near 

Eugene.  Ind.,  section  of  well  near 

Eureka,  111.,  wells  at 

Evanston,  111.,  sections  of  beach  at 

shells  found  on  beach  at 

structure  of  the  bar  near 

well  at 


Page. 

595-596 

709 

75 

132, 155 

780 

775 

592 

675 

671 

682 

145 

534-535 

-210, 238 

755 

708 

699 

577 

183-184 

617-618 

78 

79-80 

76-78 

76-82 

80-81 

58 

236 

671 

450, 451 

451 

445 

587-588 


Fairbury,  III.,  wells  at 

Fairfield,  111.,  wells  at 

Fairgrange,  111.,  wells  at 

Fair  Haven,  111.,  well  at 

Fairmount,  111.,  wells  at 

Farm  Creek,  gravel  deposits  on 

watershed  of 

Farmer  City,  111.,  section  in  boring  for  coal  at 

wells  at 

Farmington,  111.,  wells  at  and  near 686 

Farm  Eidge,  topography  near 

Fayette  County,  111.,  altitude  of 

general  features  of 

wells  in 

Fecnville.  Mich.,  wells  at 

Ferdinand,  Ind.,  col  near 

Ferruginous  conglomerate 

Fidelity.  111.,  wells  at : 

Fieldon.  Ill .,  well  at 

Findlay,  111.,  wells  at 

Fisher.  A.  J.,  infoi-mation  foruished  by 

Filbian,  111.,  wells  at 

Flint  River,  course  of 

Flora,  111.,  wells  at 

Florentia  lorniation 

Foggy,  Andrew,  well  section  of 

Ford  County,  111.,  altitude  of 

general  fi-atures  of 

table  of  deep  wells  in 

topography  of 

wells  in 

Forest.  111. ,  wells  at 

Forester.  John,  iiifomintion  furnished  by 


666 

775 

735 

613 

700 

212. 274 

514 

215-216 

705 

-687,  736 

2G0-2G1 

11 

752 

752-753 

403 

101-102 

107, 109 

747 

747 

740 

629 

700 

479 

758 

167 

53 

10 

662 

603-664 

254-255 

662-664 

666 

772 


Page. 

Forreston,  111.,  classification  of  pebbles  near 78 

wells  at 605 

Fort  Branch,  Ind..  ridged  belt  near 67-68 

Fort  Madison,  Iowa,  drift  thickness  near 52, 56,  71, 156 

Fossils,  distribution  of 165 

names  in  Pilsbry  and  Johnson's  check  list 168-171 

list  of  loess  fossils 168-174 

Fosterburg,  111.,  wells  at 749 

Fountain  Bluflf,  111.,  deflection  of  Mississippi  River  at         474 

Fountain  County,  Ind.,  wells  in 237 

Fowler,  111.,  wells  at 715 

Fowler  and  Liberty,  HI.,  drift  between 60-61 

section  in  well  between -  -  61 

Fox  Kiver,  altitude  east  of 305-306 

altitude  west  of 297-298 

belt  of  gravel  along 313 

character  of  drainage  of 498 

correlations  of  the  morainic  belt  west  of 302-304 

morainic  belt  east  of 304-305 

outwash  on 375-376 

strife  along —  415 

structure  of  drift  east  of 306-307 

structure  of  drift  west  of 300-302 

thickness  of  drift  along 283 

thickness  of  drift  east  of 306 

topography  west  of 298-299 

watershed  of 509-510 

Francisco,  Ind.,  col  near 101-102 

Franklin,  111.,  wells  at 724 

Franklin  County,  111. ,  altitude  of 11 

general  features  of —  778 

wells  in 778 

Franklin  Grove,  111.,  wells  at 609 

Freeburg,  lU.,  wells  near 761 

Freeport,  111.,  fossils  found  at 169-170 

gorge  near 494 

section  showing  "Silveria  formation"  near 112 

"Silveria  formation"  near 113 

wellat 568 

1  Friendsville,  111.,  wells  at 776 

:  FuUersburg,  HI.,  wells  at 592 

Fulton,  111.,  deflection  of  the  Mississippi  Kiver  at. . .         462 

wellsat 615 

Fulton  County,  111.,  drift  ridge  of 76 

general  features  of 686 

wells  in 686-688 

Fultz,  F.  M.,  discovery  of  glacial  strise  by 85 

Funk,  Lafayette,  information  furnished  by 695 

Funks  Grove,  111.,  wells  at 695 

Furse  Creek,  deflection  by  glacial  boundary 102 

&. 

Gallatin  County,  III.,  general  features  of 783 

wells  in 783-784 

Galesburg,  111.,  wellsat 676-677 


Galena,  111.,  wells  at 

Galewood,  111.,  well  near 

Galien  River,  drainage  basin  of 

Galva,  111.,  exposure  at 

wells  at 

Gannett,  Henry,  cited  on  magnetic  variation 

cited  on  mean  elevation  of  Illinois 7 

Garden  City,  Ind.,  auillysis  of  clay  at 411 

Garden  Plain  esker '  ^-80 

Garden  Plain,  III.,  wella  at 015-816 

Gardner.  III.,  wellsat ^~ 


565 
588 
539 
130 
624 
412 


INDEX. 


805 


Page. 
Gaa  wells  in  Illinois 557 

Geikie,  James,  cited  on  naming  of  glacial  deposits. .  19 

Genesee,  111.,  well  at 623-624 

Geneva,  111.,  wells  at 597-598 

Genoa,  111.,  wells  at 601 

Gibson,  111.,  wells  at 663 

Gibson  County,  Ind.,  change  of  drainage  in 97,98 

drift  border  in 35,  39,  40 

Giflford,  111.,  wellsnear 702 

Gilbert,  G.  K.,  cited  on  uplift  of  Niagara  outlet 453 

reference  to 84 

Gilman,  111.,  drift  sheets  at 142 

wells  at 658 

Gilmer,  111.,  well  at 581 

Girard,  111.,  wells  at 743 

Glacial  boundary 34-37, 144 

Glacial  deposits,  Chamberlin  on  names  of 19,20 

geographic  names  applied  to 19-20 

in  St.  Louis  County,  Mo 64r-6o 

near  Flummer's  Creek 69-70 

Glacial  history,  outline  of 20-21 

Glacial  striae 84-88, 105, 140-141 

Glacial  waters,  extent  on  the  borders  of  the  Missis- 
sippi River 181 

Gladstone,  111.,  soil  analysis  at 161 

Glasgow,  111.,  wells  near 722, 766 

Glavin, ,  elevations  determined  by.  -  - 433 

measurements  of  erosion  of  Lake  Michigan  fur- 
nished by 458 

Gleenwood  Beach,  description  of 428-442 

Glen  wood.  111.,  wells  near 590 

Gobies,  Mich.,  altitude  near 350 

moraine  near,  description  of 350 

well  near 366 

Godfrey,  III.,  wells  at 749 

Golconda.  111.,  wells  at 787 

Golden  Gate  Station,  111.,  wells  near 775 

Good  Hope,  111.,  well  at 686 

Gooding,  "Williarn,  report  upon  the  survey  of  the 

Illinois  River,  mentioned 418 

Goose  Lake  Channel 145 

Gordon,  C.  H.,  cited  on  preglacial  channel  of  the 

Mississippi  River 469 

cited  on  the  bowlder  bed  at  Keokuk 95 

cited  on  "Yellow  banks"  section 94 

Gossert,  S.D.,  information  furnished  by 616 

Grand  Detour.  111.,  wells  at 606 

Grand  Fork,  111.,  wells  at e 750 

Grand  Junction,   Mich.,   altitude  of  rock  surface 

near 350 

moraine  near 349 

well  at 364 

Grand  Ridge,  topography  near 260-261 

Grand  Tower,  111.,  barrier  ridge  near 14 

Gray  ville,  111.,  wells  at 777 

Great  Bear  Lake,  topography  near 348 

wells  near 355 

Greene  County,  111.,  altitude  of n 

change  of  drainage  in 102, 103 

general  features  of 744 

wells  in 744-755 

Greene  County,  Ind.,  drift  border  in 36 

striae  in 37 

Greenfield,  1 11.,  wells  at 745 

Greenleaf,  J.L.,  cited  on  descent  in  the  lower  rapids 

of  the  Mississippi  River 470 


Page. 
Greenleaf,  J.  L.,  cited  on  the  area  of  the  watersheds 

of  the  Illinois  River 496-497 

estimate  of  discharge  through  Rock  River  "Val- 
ley    489 

Green  River,  age  of  the  channel  of 493 

course  of 492-493 

Green  River  Basin,  erosion  in 492 

gravel  plain  at  head  of 277 

loess  in 793 

sand  deposits  near 277 

Greenup,  111.,  wells  at 737 

Green  Valley  Village,  111.,  wells  at 692 

Greenville,  111.,  soil  analysis  at ]62 

wells  at 75]^ 

Griggsville,  111.,  wells  at  and  near 63, 720 

Griswold,  111.,  wells  at 667 

Grundy  County,  HI.,  altitude  of 10 

genei  al  features  of 645-646 

■^ellsin 645-648 

Gumbo,  extent  of 28-33 

origin  of 29-30 

time  relations  of 30 

Hainesville,  HI.,  wells  at 531 

Hallsville,  111.,  wells  at 706 

Hamilton ,  HI.,  drift  above 53 

section  in  well  south  of 57 

strisB  near J05 

wells  at 683 

Hamilton  County,  111.,  altitude  of n 

general  features  of 777-778 

wells  in 777-778 

Hammond,  Ind.,  thickness  of  drift  at 392 

Hampshire,  111.,  wells  near 594 

Hancock  Conn  ty,  111.,  altitude  of 10 

general  features  of 681-682 

table  of  wells  in 683-684 

■^ellsin 681-684 

Hansel,  Charles,  information  furnished  by 204 

Hardin  County,  HI.,  altitude  of n 

Harman,  J.  H.,  information  furnished  by 675 

Harrington,  Mark  W.,  cited  on  the  currents  of  Lake 

Michigan 455 

Harrison  Harlan 's,  well  at 2O8 

Harristown,  III.,  wells  near 728 

Hartsbnrg,  111.,  well  at 703 

Harvard.  111.,  well  at 576 

Harvey,  III.,  well  at 590 

Haubstadt,  wells  near 67 

Havana,  111,,  wells  at 539 

Hazelhurst.  111.,  wells  at 605-606 

Hazelhurst  esker,  description  of 73 

drift  ct 79 

knolls  near 79 

Hecker,  111.,  wells  near 766 

Henderson  County,  111.,  altitude  of 10 

general  features  of 679 

wells  in 679-681 

Henderson  River,  course  of 479 

Hennepin,  111.,  well  at 634 

Henry,  111.,  wells  at 669 

Henry  County,  111.,  altitude  of 9 

general  features  of 623 

table  of  wells  in ' 625 

"wellsin 623-625 


806 


INDEX. 


Page. 

Hershey, Oscar H., aid  by 147-148,567 

cited  on  basin-like  expansion  of  the  Talley  of 

Pecatonica  River 18 

cited  on  Cedarville  gorge 495 

cited  on  Freeport  fossils 167 

cited  on  Leaf  River  or  Adeline  esker 76,77 

cited  on  rock  gorges  of  northwestern  Illinois 491,  494 

cited  on  silts  in  northwestern  Illinois Ill 

cited  on  the  physiographic  development  of  the 

Upper  Mississippi  Valley 461,462 

cited  on  transported  rock  ledges 82,  84 

cited  on  water-bedded  silt 181-182 

exposures  of  lowan  drift  noted  by 138 

fossils  collected  by 169-170 

on  eskers  in  Stephenson  and  Ogle  counties 80,82 

reference  to 552,  568 

ridge  observed  by 136 

■work  on  ■western   border   of  the  lowan   drift 

sheet 131 

Heyworth,  HI.,  section  of  well  near 215 

wells  at 695-696 

Hickory  Creek,  course  of 540 

watershed  of 505,  535 

Highland,  HI.,  ridge  from  Pocahontas  to 72-73 

wells  at 750 

Highland  Park,  111.,  wells  at 580 

Hill,  A.,  well  section  of 63 

Hillsboro,  111.,  coal  boring  at 741 

Hinckley,  HI.,  wells  at 604 

Hinde,  George  J.,  cited  on  fossiliferons  beds  near 

Toronto 189 

Hinsdale,  HI.,  wells  at 592-593 

Hobart,Ind.,  analysis  of  clay  at 411 

t  bickness  of  drift  at 392 

Hoffman's,  F.  N.,  well  at 587 

Hagar,  ilich.,  section  near 395 

Hog  Run,  watershed  of 508-509 

HoUandsville,  HI.,  wells  at 749 

Homer,  HI.,  wells  near 703 

Hoopeston.  HI.,  wells  at 698-699 

Hopedale,  HI.,  well  at 214,692 

Houston,  HI.,  wells  near 768-769 

Hoyleton,  111.,  wells  near 770 

Humboldt,  wells  near 221 

Hutchinson's  Lake,  wells  near 402 

I- 

Ice  dispersion,  centers  of 21-22 

Ice  invasion,  efl«ct  of  the  Hlinoian,  on  the  outer  bor- 
der d  rainage 89-105 

Ice  sheet,  direction  of  retreat  of 427-428 

in  Mississippi  Talley,  drainage  of 71 

Ideal,  111.,  wells  near 613 

Hlinois,  altitudes  in 7-12 

area  of 12 

barrier  ridge  in  southern 14 

changes  in  drift  in  central 28 

bowlders  in  eastern 198 

composite  mor;iinic  belt  of  northern 290-307 

distribution  of  drift  in,  by  depths 548 

drift  in  southern 65 

elevated  liraestono  belt  in 16 

elevation  of  glacial  lobe  of 179 

esker  ridges  of  northwestern 76-82 

extent  of  gumbo  in 28-33 


Page. 

Illinois,  gravelly  soils  in 792-793 

knolls  in  the  vicinity  of  drift  border  in  southern.  39 

loess  in  northern 154 

measurements  of  rock  gorges  in  northwestern. .  494 

mounds  of  ^Niagara  limestone  in 16 

paha  in 134-135 

residuary  soils  in 791 

rock  gorges  of  northwestern 493-496 

rock  gorges  in  western 496 

sections  of  drift  in 33-34 

silt  deposit  insonthem 116 

silt  in  western 794 

soils  in  (table) 790-791 

sources  of  soil  material  in 788 

strife  in  northeastern 415 

structure  of  drift  in 27-28 

thickness  of  drift  in 27 

till  in 28 

till  in  Ohio  Valley  in 65-66 

topographic  character  of  the  drift  border  in 38-40 

topography  of  drift  in 26-27 

wells  in  unglaciated  counties  of 784-787 

white  clay  in  southern 795 

Hlinois  and  Iowa  ice  lobes,  relation  of  the 151-153 

Hlinois  River,  altitudes  near 15 

altitudes  of  rock  floor  and  present  lower 501 

composition  of  ridge  between  Mississippi  River 

and 60-61 

course  of  upper 501-502 

deposits  along 498 

deposits  at  the  head  of  the 423 

depression  north  from  Beardstown,  in  valley  of.  500-501 

divisions  of  valley  of 498-499 

drainage  area  of  the  tributaries  of 497 

drift  border  east  of 64 

drift  structure  along 284 

erosion  belowthe  Morris  Basin  in 423 

extent  of  the  watershed 496-497 

former  lake  at  the  bead  of 337 

gravel  deposits  in  the  valley  of 275, 276 

loess  in  valley  of 156 

preglacial  and  postglacial  condition  of 422 

Shelby  ville  moraine  east  of 214 

structure  of  drift  west  of 213-218 

topography  between  Mackinaw  River  and 251-252 

topography  west  of 250-251,  280-281 

variations  in  the  bed  of  Upper 502 

wells  west  of 207 

Hliopolis,  111."  wells  at 725 

Indian  Creek,  sand  ridge  near 329-330 

watershed  of 521 

Indiana,  altitudes  in 7.405 

change  in  drainage  in  southwestern 97-104 

drift  in  south  western 66-67 

elevated  tract  of  conglomerate  sandstone  in 16-17 

"bill  country"  of 16 

strife  in  northwestern 414 

till  in  southwestern 66-67 

western,  thickness  of  Shelby  ville  drift  in 199-200 

Indianola,  111.,  wells  at 700 

lola.  111.,  wells  near 758 

Iowa,  altitudo  of 7 

structure  of  drift  border  in  soulbeaatern 40-43 

Iowa  ice  lobes,  relation  of  the  Illinois  and 151-153 

Iowa  River,  section  of  well  in  valley  of 50 

lowan  drift  sheet  of  the  Illinois  lobe,  distribution  of.  131-134 


INDEX. 


807 


lowan  drift  sheet,  probable  extent  of  tbe  Iowa  por- 
tion of  tho 

probable  extent  of  Wisconsin  sheet  beneath 

soil  and  peat  between  Wisconsin  sheet  and 

structure  of 

thickuess  of 

topography  of 

lowan  loess,  character  and  occurrence  of 

distribution  of 

raineraloglcal  constitution  of 

size  of  the  grain  of. 

structure  of 

variations  in  thickness  of 

variations  in  structure  of 

lowan  outline  compared  with  succeeding  and  pre- 

cedi ng  glaciations 

Ipava,  111.,  well  at 

Irene,  111.,  wells  in 

Iroquois,  111.,  well  at 

Iroquois  Basin,  outwash  in 

sand  near,  coarseness  of 

Iroquois  County,  111.,  altitude  of 

drift  sheets  in 

general  features  of 

soil  horizons  in 

topography  in 

topography  of  moraine  in 

wells  in 

Iroquois  moraine  sand  deposits,  interpretation  of... 
Iroquois  Kiver,  outwash  along  basin  of 

sand  area  near 

watershed  of 

Irving,  R.  D.,  cited,  on  preglacial  basin  of    Lake 

Michigan 

Isabel,  111.,  wells  near 

Itasca,  111.,  wells  near 


Page. 

144-153 
141-144 
185-186 
137-140 
136-137 
134-136 
153-165 
153-155 

159 
158-159 
156-164 
155-156 

157 

188 

688 

575 

659 

323 

333-334 

11 

142-143 

654^656 

265-266 

282 

258 

654 

336-337 

314 

331 

507-508 

7 
733 
592 


Jackson  County,  111.,  altitude  of 11 

general  features  of 778-779 

atrins  in 87 

wells  in 778-780 

Jackson  and  Randolph  counties.  111.,  ridge  in 73-74 

Jackson  and  Williamson  counties,  111.,  strise  in 87 

wells  in 780-781 

Jackson  Creek,  watershed  of 505 

Jacksonville,  lU.,  wells  at 723 

JanesviUe,  Wis.,  preglacial  valley  near 483-484 

Jasper  County,  111.,  altitude  of 11 

general  features  of 754 

wells  in 754-755 

Jefferson  County,  111.,  altitude  of 11 

general  features  of 773-774 

wells  in 773-774 

Jenkins,  O.  P.,  information  furnished  by 412 

Jersey  County,  111.,  general  features  of 746-747 

wells  in 746-747 

Jersey  ville,  111.,  wells  at 747 

Jo  Daviess  County,  111.,  altitude  of 9 

area  of 564 

wells  in 564-567 

Johnson  Countj'",  111.,  altitude  of 11 

Johnson  Creek,  111.,  exposure  at 129-130 

Johufion's  Mound 299 

Joliet,  111.,  strige  at 415 

wells  at 649-650 


Joliet  Mount,  111.,  section  of 377 

Joy.  111.,  well  near 623 

Kalamazoo  River,  depth  of 441 

drainage  basin  of 541 

moraine  along,  description  of 349 

sand  plains  near 436-437 

wells  in  valley  of 359 

Kane  County,  111.,  altitude  of 9 

area  and  general  features  of 594 

bowlders  in 268 

wells  in 594-599 

Kane  and  Kendall  counties,  means  of  deposition  of 

gravelly  plain  in 323-324 

Kaneville,  111.,  wells  near 598-599 

Kaneville  esker,  description  of 284-286 

Kankakee  Ilk,  wells  at 653 

Kankakee  Basin,  character  of 498 

Kankakee  County,  111.,  altitude  of 10 

general  features  of 653 

wells  in 653-654 

Kankakee  Lake,  interpretations  of  the  sand  deposits 

known  as 334-338 

Kankakee  River,  bowlders  along 325-326 

deposits  along 378-379 

descent  of  the 506-507 

drainage  basin  of 505-507 

sand  deposits  along 322-323 

sand  near,  thickness  of 333 

topography  near 332-333,347 

till  plain  along  valley  of 324-325 

Kansan  drift  sheet,  erosion  of  the 121-123 

Kansan  till,  extent  of 105 

Kansas,  111.,  wells  at 217,733 

Kansas  City,  Mo.,  analyses  of  loess  at  (table) 164 

Kaskaskia  Basin,  origin  of  the  ridges  of  the 73-74 

ridged  drift  of  the 71-74 

topography  of  ridges  in 72-73 

Kaskaskia  River,  bluff  of,  section  of 739 

course  and  watershed  of 523-524 

drift  in  valley  of 202-203 

outwash  in  valley  of 210,  238 

Keithsburg,  111.,  wells  at 622 

Kendall  County,  111 .,  altitude  of 10 

general  features  of 643 

table  of  wells  along  the  Marseilles  moraine  in. . .  645 

wells  in 643-645 

Kendall  and  Kane  counties,  III.,  gravel  plain  in,  three 

means  of  deposition  of 323-324 

Kenney,  111.,  well  at 706 

Keokuk,  Iowa,  bowlder  bed  at 95-96 

"Yellow  banks,"  section  near 94 

Kee watin  ice  sheet,  limits  of 22 

Kent  Creek,  gorge  on 492 

Kent,  111.,  well  at 568 

Kewanee,  III.,  wells  at 624 

Kickapoo  Creek,  gravel  filling  along 271-272 

outwash  in  valley  of 276 

terraces  of  gravel  along 212 

watershed  of 513-514,  519 

Killbuck  Creek,  sand  and  gravel  deposits  along 278 

Kimball,  111.,  wells  near 755 

Kingsley,  Robert,  information  furnished  by 372 

Kings  Station,  111.,  wells  near '. 607 

Kingston,  111.,  wells  at 60 


808 


INDEX. 


Page. 

Einmnndy,  HI.,  wells  at "59 

Kisb wankee  River,  effect  of  glaciation  on 485 

baried  soil  in  Tallev  of 293 

gravel  plain  in  valley  of 294 

wells  along 600 

Kite  River,  coorse  of iS6 

preglacial  excavation  in  valley  of 4S9 

preglacial  excavation  sooth  of 489 

sand  and  gravel  deposits  along 278 

Kite  and  Leaf  preglacial  rivers,  excavation  on  di- 
vide between - 489 

Knolls  in  Logan  Coonty,  HI 75 

in  the  vicinity  of  drift  border  in  sontbem  niinois  39 

near  Hazelhurst  esfeer 79 

Knowlton.  F.  H.,  on  plant  remains 31 

Knox  County.  HI.,  altitude  of 10 

general  features  of.. 676 

views  in  cuttings  along  Santa  Fe  Railway  in 

eastern 126 

wells  in 676-678 

Knoxville,  HI.,  wells  at 677 

Labradorian  ice  field,  limits  of 23 

Lacon,  HI.,  wells  at 669 

Lagrange,  HI.,  gravel  pit  between  Salt  Creek  and. . .         438 

wells  at - 589 

Laharpe.Hl.,  wells  at ^ 682 

Lahogue,  HI.,  wells  at 658 

Lake  Chicago,  discussion  of  the  emergence  of  the 

beaches  of 442 

elevation  of 435 

elevation  of  upper  beach  of 437-43S 

outlets  of,  at  the  time  third  beach  was  forming. .  452 

Lake  County.  HI.,  altitude  of 10 

general  character  of 579 

wells  in 579-581 

Late  Forest,  111.,  weUs  at 580 

Lake  Hennepin 152,153 

Lake  Michigan,  bulk  of  the  beach  of 454 

depths  of  lakes  tribniarj-  to 441 

drainage  basin  of 538 

erosion  of  the  shore  of 456-459 

estimated  age  of 459 

evidence  of  emergence  along  east  shore  of 441 

marl  beds  along 797 

present  beach  of 453-459 

present  movement  of  the  border  of 453-454 

profiles  across 12-13 

section  of  bluff  of 395 

structure  of  drift  around  the  head  of 356 

water  movements  in 455-456 

Lake  Richland 103 

Lake  St.  Clair,  deposits  along  the  head  of. 425 

Lake  Znrich.  HI.,  wells  near 531 

Lakeside  Station,  Mich.,  beach  near 433 

Lamoille,  111.,  wells  at 627 

Lanark,  dl..  wells  at 612 

"Lanes  Island,"  HI.,  wells  on ^0 

Lasalle,  HI.,  wells  at 637 

Xasalle  County.  111.,  altitade  of 10 

buried  soil  in 264 

general  features  of 635-636 

table  of  wells  al  on  glfarseillea  moraine  in  eastern .  6:t9-.641 
table  of  wclU  in.  outside  of  Marseilles  moraine. .  641-647 
wells  in 635-^2 


Page. 

Lawndale,  HI,  wells  at 708 

Lawrence.  Mich.,  generalized  section  of  wells  at 371 

Lawrence  Cotmty,  HI.,  altitude  of 11 

general  features  of 756 

wells  in 756 

Lawrenceville,  111.,  wells  at 756 

Leaf  River,  course  of 4fi5 

cuttingalong  preglacial  valley  of 486 

excavation  on  the  divide  between  the  preglacial 

Kite  Riverand... 459 

preglacial   excavation    along    soath   tributary 

of 489 

Leaf  River  or  Adeline  esker,  description  of 76-78 

Lebanon,  HI.,  wells  at 763 

Leclaire.  deflection  of  the  Mississippi  Rivw  at 463-464 

drift  at 464 

Lee  County.  HL,  altitude  of 9 

bowlders  in 268 

buried  soil  in 264 

general  features  of 608 

table  of  deep  wells  in  eastern  and  southern 610 

wells  in 608-611 

Lee  County,  Iowa,  drift  in 52 

old  channel  of  the  Mississippi  River  in 93-94 

red  jaspery  in 24 

Lee  Station,  well  at 364 

Lementon,  III.,  coal  boring  at 764 

Lemmon,  FUa.  acknowledgments  to 627 

Lemont,  glaciated  surface  near 416-417 

Lfpus  siflraticug 42 

Lena,  HI.,  well  at '. 568 

Lema,  wells  at 202.736 

Leroy.Hl.  wells  at 215.695 

Letts.  Iowa,  wells  near 49 

Leverett.  Frank,  cited  on  beaches  of  Lake  Michigan .  419 

cited  on  glacial  history 21 

cited  on  interglacial  interval. ..'. 41 

cited  on  low  altitude  at  St.  Paul 475 

cited  on  rock  borings  at  Princeton 500 

cited  ou  the  deflection  of  Big  Cedar  Creek 90 

cited  on  the  lower  rapids  of  the  Mississippi 

River 470 

cited  on  the  relation  between  the  Hlinoian  till 

sheet  and  the  lowan  loess 25 

cited  on  soil  horizon  in  eastern  Illinois 186 

cited  on  wells  of  northern  Indiana 359 

fossils  collected  by 169 

quoted  on  the  naming  of  "Lake  Chicago" 427 

reference  to 24.88,125 

Lewistown.  HI.,  wells  at 688 

Lexington,  gravel  deposits  at 279 

Liberty.  111.,  drift  between  Fowler  and GO-61 

section  in  well  between  Fowler  and 61 

wells  at 716-717 

Lily  Lake,  HI.,  section  of  boring  near 294 

Limestone  mounds 16 

Limestone  ridges 14-16 

Lincoln.  111.,  well  at 708 

Lindcrwood.  HI.,  wells  near 607 

Lisbon,  HI.,  wells  near 644-645 

Lis'.e.  HI.,  wells  near 593 

Litchfield,  111.,  wells  at 741 

Uttle  Rock  esker  description  of 286-288 

Little  VemiilioD  River,  watershed  of 519 

Little  Wabash  River,  course  and  watershed  of 530-531 

section  of  bluff  of 758 


INDEX. 


809 


Page. 

Livingston  County,  111.,  altitude  of 10 

general  features  of 664^665 

table  of  wells  in 667-668 

wellaiu 664-668 

Lobes,  relation  of  the  Illinois  and  loAva  ioL' 151-153 

Lockport  limestone,  mounds  of 16 

Loda,  111.,  -wells  at 662 

Loess,  PEolian 183-184 

analyses  of 158-164 

discussion  of 32 

leached,  beneath  the  Wisconsin  drift 187-188 

mode  of  deposition  of 176-184 

Ustof  fossils  of  the 168-17'i 

relation  of  blaff  to  upland 182-183 

relation  of  gummy  clay  to 31 

Logan  County,  111.,  altitude  of 10 

general  features  of 707 

knolls  in 75 

wells  in 707-709 

Lombard,  111.,  wells  at 593 

Long  Grove,  Iowa,  bowlders  near 147-148 

Logootee,  Ind.,  drift  border  at 36, 69 

Lost  Creek,  effect  of  glaciation  on 480 

Louisville,  111.,  well  at 758 

Loveless,  James,  well  section  of 61 

Lowder,  111.,  wells  near 725 

Ludlow,  111.,  wells  near 702 

Lynn  Center,  111.,  wells  near 625 

Mackinaw,  111.,  wells  at 692 

Mackinaw  Kiver,  gravel  deposit  on 273 

terrace  on 211-212 

terrace  in  valley  of 273-274 

topography  between  Illinois  Kiver  and 251-252 

topography  east  of 252-254 

topography  near 282 

watershed  of 5]  4 

Macomb,  111.,  well  at 685-686 

Macon,  111.,  drift  at 203 

well  at 729 

Macon  County,  111.,  altitude  of 10 

general  features  of 727 

wells  in 727-729 

Macoupin  County,  general  features  of 742 

wells  in 742-744 

Macoupin  Creek,  watershed  of 522 

Madison  County,  111.,  altitude  of 10 

general  features  of 748-749 

till  in 64 

wells  in 748-750 

Mahomet,  111.,  outwash  at 237 

wells  and  exposures  at  and  near 216-217, 703 

Manchester,  111.,  wells  near 722 

Manistee,  Mich.,  drift  at 13 

Mansfield,  111. ,  well  at 704 

Manvaise  Terre  Creek,  watershed  of 521-522 

Marcy,  Oliver,  section  of  beach  taken  by 450 

shells  collected  by 451 

Marengo,  HI.,  wells  at 577. 

Marengo  Kidge,  gravel  plain  on  inner  border  of 295 

iLarengo  Ridge  moraine,  correlations  of 295-296 

distribution  of 290-291 

relief  of 291 

structure  of  the  drift  in 293-294 

thickness  of  the  drift  in 29^293 


Page. 

Marengo  Ridge  moraine,  topography  of 291-292 

Marion,  111.,  wells  near 781 

Marion  County,  111.,  altitude  of ll 

general  features  of 758-759 

wells  in 758-760 

Maroa,  111.,  wells  at 729 

Marseilles,  HI. ,  wells  at 638 

Marseilles  moraine,  altitude  of 309 

distribution  of 307-308 

structuro  of  drift  of 312-313 

thickness  of  drift  along 311-312 

topo^iraphyof 309-311 

Marsh,  G.  C,  Information  furnished  by 397 

Marshall,  W.  L.,  report  on  Chicago  Outlet  mentioned  419 

Marshall,  111.,  exposure  of  Sangamon  soil  at 129 

wells  at 734 

Marshall  County,  111.,  altitude  of 10 

bowlders  in 269 

general  features  of 668-669 

wells  in 668-669 

Martin  County,  Ind.,  changes  of  drainage  in 102 

drift  border  in 36 

Martinton,  111.,  wells  at 656 

Mascoutah,IU.,  coal  shaft  at 764 

Mason,  111.,  wells  at  and  near 689,754 

Mason  County,  111.,  altitude  of 10 

general  features  of 688 

wells  in 688-689 

Material  in  the  abandoned  channel  of  the  Mississippi       93-94 

Matteson,  III.,  wells  near 590 

Mattoon,  111.,  section  of  drift  in  coal  shaft  at 202 

wells  at 735 

Mayview,  111.,  wells  near 702 

Maywood,  111.,  wells  near 588-589 

Mazon,  111.,  wells  at 647 

Mazon  Creek,  watershed  of 508 

McCuen,  W".,  well  section  of 57 

McDunougli  County,  III. ,  altitude  of 10 

general  features  of 685 

wells  in 685-686 

McGee,  W  J,  cited  on  border  of  lowan  drift 144,146 

cited  on  gum  bo 31 

cited  on  the  draiuage  systems  of  eastern  Iowa. .  91 

cited  on  the  relation  of  the  lllinoiau  to  the 

lowan  drift 25 

cited  on  the  relation  of  the  Illinois  and  Iowa  ice 

lobes 151-152 

McGee,  W  J,  and  Calvin,  S.,  cited  on  lowan  and 

Kansan  sheet  of  northeastern  Iowa 139 

McGee,  W  J,  and  Udden,  J.  A.,  cited  on  the  displace- 
ment of  the  Mississippi 90 

McHenry  County,  111.,  a] titude  of 9,  575 

situation  and  area  of 575 

wells  in 575-579 

McKee's  Creek,  watershed  of 521 

McLean  County,  Hi. ,  altitude  of 10 

buried  soil  in 265 

general  features  of 692-693 

ridge  in 244 

table  of  wells  in 696 

wells  in 214-215, 692-697 

McLeansboro,  111.,  wells  at 778 

McWendle,  William,  information  furnished  by 386 

Mead,  Daniel  W.,  information  furnished  by 572 

well  records  from  report  of 556 

Medora,  III.,  coal  boring  at 743 


810 


INDEX. 


Page. 

Meaard  County,  111.,  altitude  of 10 

general  features  of 709 

wellain 709-710 

Mendon.IU.,  -wells  at 715 

Mendota,  m, -wella  at 636-637 

Mephiticus  tncphitica 42 

Mercer  County,  111.,  altitude  of --  9 

general  features  of 622 

wells  in 622-623 

ileriam,  111.,  wells  near 775 

Metaniora,  111.,  wells  at 672 

Metropolis  City.IU.,  wells  3iear 785 

Michigan,  drift  in  southwestern 353 

Michigan  City.  Ind.,  analysis  of  clay  at 411 

depth  of  gravel  at 430 

section  of  boring  at 397 

section  of  well  at 398 

thickness  of  drift  at 392 

Milan,  111.,  fossils  found  near 174 

well  at 621 

Milburu,  111.,  wells  at 580 

Miles,  Iowa,  drift  at 146 

Milford,  111.,  drift  sheets  at 143 

wells  near 660 

Mill  Creek,  fossils  found  at 174 

Milledgeville,  111  ,  well  at 613 

Miller,  Jacob,  information  furnished  by 628 

Millington,ni.,  wells  at 644 

Millstadt,  111.,  wells  at 762 

Milton,  111.,  wells  near 720 

Milwaukee,  Wis.,  profile  across  Lake  Michigan  at. . .  13 

Minonk.m.,  wells  at 670-671 

Minooka,  HI.,  wells  at 647 

Minooka  till  ridge,  distribution  of 319 

probable  line  of  continuation  of 319-320 

structure  of  drift  on 321 

thickness  of  drift  near 320-321 

topography  near 320 

Mississippi  bluff,  section  at  Muscatine,  Iowa 47-48 

Mississippi  Eiver,  altitude  of  rock  bottom  and  pres- 
ent river 474-476 

composition  of  ridge  between  Illinois  River  and .      60-61 

deflection  at  Leclaire 463-464 

deflections  of,  south  of  glacial  boundary 474 

determination  of  the  date  of  excavation  of  lower 

rapids 470-473 

elevation  of  the  abandoned  channel  of  the 93 

limestone  belt  along 14 

material  in  the  abandoned  channel  of  the 93-94 

preglacial  course  of,  below  Clinton 466-467 

reestablishment  of,  below  the  lower  rapids 473-474 

temporary  displacement  of  the 89-97 

Mississippi  Valley,  artesian  wells  in  the 56 

drainage  for  the  ice  sheet  in  the - 71 

relative  sizes  of  the  present  and  preglacial 468-469 

wells  in 565 

Missouri,  glacial  deposits  in  St.  Louis  County 64 

Mitchell.  Joseph,  information  furnished  by 125 

Moccasin,  111.,  wells  mnxr 754 

Modesto,  111.,  wells  at 743 

Molino,  111.,  fossils  found  at 170-171 

Momence,  III.,  limestone  at 506 

wells  at 653 

Monmouth,  111.,  wells  at 678 

Monon  Creek,  sand  ridge  near 330 

Mouro(\  HI.,  wells  at 607 


Page. 

Monroe  County,  III.,  altitude  of 16 

general  features  of 765 

wells  in 765-766 

Mont  Clare,  artesian  well  at 56 

Monroe  County,  Ind.,  changes  in  drainage  in 104 

drift  border  in 36,  70 

Montgomery  County,  111.,  altitude  of 11 

general  features  of 740-741 

wells  in 740-742 

Montgomery  County,  Ind.,  wells  in 237 

Monticello,  HI.,  section  of  well  at 220 

wells  at 704 

Morgan.  County,  111.,  altitude  of 11 

general  features  of 722 

wells  in 722-724 

Morgau  County,  Ind.,  drift  border  in 70 

Morgan  Park,  ill.,  well  at 589-590 

Morris,  111.,  wells  at 647 

Morris  Basin,  deposits  at  the 423 

till  plain  near  the ^^15 

Morrison,  HI.,  exposure  of  till  at 140 

loess  at 149 

ridges  near 134, 150 

wells  near 617 

Morrisonville,  HI.,  wells  at 727 

Morton,  HI.,  wells  at 214, 583, 691 

Moweaqua,  111.,  well  at 738 

Moultrie  County,  III. .  altitude  of 10 

general  features  of 729-730 

wells  in 729-730 

Mound  Station ,111.,  wells  at 713 

Mount,  J- H..  information  furnished  by 206,207 

Mount  Auburn,  111.,  wells  at 726 

Mount  Carmel,  111.,  wells  at 611-612,776 

Mount  Carroll,  III.,  exposures  at 129-130 

Mount  Morris,  111.,  wells  at 605 

Mount  Pleasant,  Tnd.,  drift  border  near 36,69 

MountPulaski,  111.,  wells  at 709 

Mount  Sterling.  III.,  wells  at 713 

Moweaqua,  HI.,  soil  analysis  at 162 

Muck,  buried,  at  Belleville,  111 763 

at  Bethany,  III 730 

atHalton  City,  111 217 

atBelavan.Hl 206-207,691 

at  Hopedale,  HI 214.692 

at  Leroy.  Ill 695 

at  Mahomet,  111 703 

at  iletamora.Ill 672 

at  Mount  Carroll,  111 139-130 

atPana.Ill 726 

at  Rock  Island,  HI 114 

at  Windsor,  111 202,739-740 

in  Christian  County,  111 725 

in  Hewitt  County,  III 705 

iuFord  County.  Ill 663 

in  Lasalle  County,  111 641,642 

in  Lee  County,  Iowa 41 

in  McLean  County,  111 265,696,097 

in  northern  Illinois 185-186 

in  Rock  Island  County,  HI 620,621 

in  Vermilion  County,  111 698 

in  Verniilinn  County,  Ind 233 

near  Areola.  Ill 731 

near  Alta,  HI 207,674 

near  Danville  Junction,  111 699 

near  Garden  Plain,  111 61.'S 


INDEX. 


811 


Muck,  buried,  near  Hamilton,  HI. 

near  Hey  worth,  111 

near  Letts,  Iowa 

near  Marengo,  111 

near  New  London,  Iowa 

near  Omaba,  111 

near  Reynolds,  Ind 

near  Springfield,  111 


57 

215 

49 

577 

52 

783 

335 

125 

near  Time,  111 63-64,  721 

near  Wapella,  111 215 

near  Yariuoutli,  Iowa 51 

{See  Peat,  buried;  Silt,  buried;  Soil,  buried.) 

Murphy sville,  111.,  wells  at 780 

Muscatiue,  Iowa,  exposures  at 46-48 

foasils  found  at 168-169, 174 

section  of  Mississippi  bluff  at 47^8 

Muscatine  County,  Iowa,  character  of  wells  in 49 

drift  border  in 34, 144 

di  ift  sections  in 46-49 

Muskegon,  Mich.,  drift  at 13 

Muskegon  Lake,  depth  of 441 

isr. 

Nachusa,  111.,  wells  at 609 

Names  of  fossils  in  Pilsbry  andJohnson's  checklist.  168-171 

IS'aperville,  111.,  wells  at 593-594 

Nashville,  111. ,  wells  at 770 

Nauvoo,  111.,  wells  at 682 

Nebo,  111.,  wells  at 721 

Neoga,  111.,  wells  at ...  737 

Neponset,  drift  beds  in  coal  shaft  at 629 

Nettle  Creek,  watershed  of 508 

Nevada,  111.,  wells  at 666 

Newark  limestone 36,  70, 102 

New  Athens,  111.,  wells  at 765 

New  Berlin,  111.,  wells  at 725 

New  Bremen,  111.,  wells  near 590 

New  Buffalo,  Mich.,  beach  at 432-433 

depth  of  gravel  at 439 

sheets  found  near 440 

thickness  of  drift  at 392 

New  Haven,  111.,  knoils  near 39 

New  Lebanon,  111.,  well  at 601 

New  London,  Iowa,  sections  of  wells  near 51,  52 

New  Salem,  III.,  wells  at 63,720 

Newton,  Adams  County,  111.,  section  in  well  south- 
east of 59 

Newton,  Jasper  County,  111.,  wells  near 754 

Newtown,  111.,  wells  near 717 

New  Troy,  Mich.,  thickness  of  drift  at 392 

till  at 399 

Niagara  limestone,  mounds  of iq 

Niagara  outlet,  uplift  of 453 

Niantic,  111.,  coal  shaft  at 728 

Nicklea,  J.  M.,  cited  on  Pleistocene  deposits  near 

Sparta,  HI 117 

reference  to 769 

Niles  Center,  111.,  wells  at 588 

Nil  wood,  111 ,  wells  at 743 

Nokomis,  111.,  wells  at 741 

Noyes,  W.  A.,  analyses  made  by 164,411 

O. 

Oak  Glen,  111.,  wells  at 587 

Oakland,  111.,  wells  at 735 

Oak  Park,  111.,  section  in  gravel  pit  near 438 

sheets  found  near 439-440 


Page. 

Oblong,  111.,  wells  near 750 

Odell,  HI.,  wells  at 666 

Odin,  HI.,  coal  boring  at 759 

Ogle  County,  111.,  altitude  of 9 

bowlders  in 268 

general  features 604-605 

sand  and  gravel  in  eastern 278 

wells  in 604-608 

Ohio,  111.,  well  at 629 

Ohio  Corners,  well  near 361 

Ohio  Valley,  HI.,  tillin : 65-66 

Old  Ripley,  111.,  wells  at 751 

Olmstead,  111.,  wells  at 787 

Olney,  HI.,  wells  at : 757 

Omaha,  111.,  wells  near 783 

Onarga,  111.,  drift  sheets  at 142 

wells  at 658 

Onarga  Ridge,  description  of 289-290 

Onslow,  Iowa,  drift  at 145 

Outarioville,  lU.,  well  at 585 

Oquawka,  111.,  wells  at 680 

Orangeville,  HI.,  belt  of  gravelly  drift  near 81 

wells  near 568 

Oregon,  111., drift  bordernear 132 

wells  at 606 

Organic  remains 123-124 

Orion,  111.,  wells  near 625 

Orr,  John,  information  furnished  by 397 

Oswego,  HI.,  wells  at 644 

Ottawa,  111.,  topography  near 281-282 

wells  at 638 

Otter  Creek,  watershed  of 523 

Otterville,  111.,  wells  at 747 

Otwell,  111.,  borings  at 68,  99 

Overhall,  D.,  well  secticn 749, 750 

O verisel,  wells  at 439 

Owen  County,  Ind.,  drift  border  in 36, 70 

strije  in  Oreene  County  and 87 

Owens  Creek,  sand  and  gravel  deposits  along 278 

Palatine  Township,  HI.,  wells  in 585-586 

Palmer,  111.,  coal  shaft  at 727 

Pana,  111.,  section  of  well  at 107 

wells  at 726 

Papineau,  111.,  wells  at 656 

Paris,  111.,  classification  of  pebbles  at 221 

wells  at 732-733 

well  at 201 

Parke  County ,  Ind.,  drift  in  western 200 

wells  in 237 

Park  Ridge,  HI.,  wells  at 587 

Parnell,  111.,  well  near 705 

Patoka,  111.,  wells  at - 759 

Patoka,  Ind.,  change  in  drainage  near 100, 101 

Patoka  River,  preglacial  and  present  course  of 99-1 02 

watershed  of 532 

Pawpaw,  111.,  well  at 611 

Pawpaw  Lake,  ^ell  near 370 

Pawpaw  River,  bay  in.  the  valley  of 435 

course  of 540-541 

moraine  near,  descriptitm  of 350-351 

sandy  belt  near 369 

Pawpaw  Swamp,  moraine  near 341-342 

Paxton,  111.,  wells  at 662-663 

Payson,  III.,  wells  near 59,717 


812 


INDEX. 


Page. 

Peat,  buried,  at  Ashland,  111 127 

at  Champaign,  111 2i4 

atEvanston.Ill 450,588 

at  Muscatine,  Iowa -18 

at  Neponsct,  111 629 

at  Virginia,  111 711 

in  Christian  County,  111 725 

in  Des  Moines  County,  Iowa 50 

ill  Iroquoia  County,  111 141.655.  656 

in  Lee  County,  Io\ra 41 

in  northern  Illinois 185-186 

in  southeastern  Iowa -  - .  120-121 

near  Chel)anse,  111 657 

near  Clayton,  111 141-U2.661 

near  Da ven  port,  Iowa 128 

near  Edwards  River 622 

near  Letts,  Iowa 49 

near  Mahomet,  III 216 

near  New  London,  Iowa 52 

near  Reynolds,  Ind 335 

near  Washington,  111 32 

near  Wyom  ing,  111 672 

(See  Mucl;,  buried;  Silt,  buried;  Soil,  buried.) 

Pecatonica,  111.,  wells  at 572 

Pecatoniea  Easin,  structure  of  drift  in 137-138 

Pecatonica  esker  system 80-81 

Pecatonica  River,  basin-like  expansion  of  valley  of.  18 

effect  of  glaciation  on 484-485 

Peet,  S.  Conformation  furnished  by 686 

Pekin,  111.,  wells  at 691 

Penhallow,  D.  P.,  cited  on  Toronto  formation 189 

Pentwater  Lake,  depth  of 441 

Peoria,  111.,  exposures  near 128,207 

glacial  deposits  near 499 

width  of  the  Illinois  Valley  at 499-500 

Peoria  County,  111.,  altitude  of 10 

bowlders  in 269 

general  features  of 673 

wells  in 073-676 

Peorian  stage,  length  of 188-189 

Pere  Marquette  Lake,  depth  of 441 

Perry  County,  111.,  altitude  of 10 

general  features  of 771 

wells  in ■ 771-773 

Peru,  111.,  altitude  of  rock  bottom  at 500 

wells  at 637 

Petersburg,  111.,  wells  at 709 

Philipstown,  111.,  \\ells  near 777 

Philo,  111.,  section  of  well  at. 235-236 

wells  at 703 

Phinney,  A.  J.,  cited  on  geologic  formations  in  west- 
ern Indiana 552 

Piatt  County,  111.,  altitude  of 10 

general  features  of 703-704 

well  in 234,  703, 704 

Pigeon  Creek  drainage  basin,  changes  in 98 

Pike  County,  111.,  altitude  of 11 

dril't  border  in 34 

general  features  of 718-719 

till  in 62 

wells  in 718-721 

Pike  County,  Ind.,  changes  in  drainage  in 98,  99 

drift  border  in 35, 37, 40 

drift  in 68 

till  in 68-ti9 

Pillsbry  and  Johnson's  check  list,  cited 168-171 

PincUni-yvillo,  111.,  wells  at 771 


Pine  Creek,  preglacial  excavations  along  Rock  River 

near 

Pipestone  Creek,  course  of 

topography  near 

wells  near 

Pipestone  River,  moraine  near,  description  of 

Pittstield,  111.,  wells  at 

Pitt  wood.  111.,  wells  at 

Plainville,  III.,  drift  near 

wells  at 

Piano,  111. ,  wells  at 

Plattville,  111.,  wells  near 

Pleasant  Mound,  111.,  wells  at 

Pleasant  Plain,  111.,  wells  at 

Pleasant  Valley,  preglacial  stream  in 

Pleasant  View,  III.,  wells  at 

Pleistocene  beds  near  Sparta,  111.,  section  of 

Pleistocene  deposits  beneath  thelllinoian  till  sheet. 

Plunimers  Creek,  glacial  deposits  near 

Plum  River,  preglacial  and  present  course  of 

Pocahontas,  111.,  ridge  from  Highland  to 

Polo,  111.,  exposures  of  lowan  drift  east  of 132, 

wells  at 

Pontiac,  111.,  wells  at 

Pope  County,  111.,  altitude  of 

Porter  County,  Ind.,  section  of  artesian  well  in 

thickness  of  drift  in 

Posey  County,  Ind.,  changes  of  drainage  in  

drift  in 

Potomac,  111.,  wells  near 

Prairie  City.  111.,  wells  at 

Prairie  Creek,  HI.,  wells  near 

Pratt,  W.  H.,  cited  on  animal  remains  in  Davenport, 
Iowa 

cited  on  fossils 

Prentice,  111.,  coal  shaft  at 

Princeton,  111.,  altitude  of  rock  bottom,  at 

wells  at 

Princeville,  111.,  wells  near 

Prophetstown,  111.,  wells  near 

Prospect  Park,  111.,  wells  at 

Pula.ski  County,  111.,  altitude  of 

I'urdue,  A.  H.,  aid  by 

■  work  on  sand  areas 

Purviance,  A.  T.,  information  furnished  by 

Putnam  City,  111.,  well  at 

Putnam  County,  111.,  altitude  of 

genenil  features  of 

wells  in 


Q. 


Qnincy,  HI.,  wells  at 

Quiver  Creek,  watershed  of  , 


189 
540 
348 

372-373 
352 
721 

(i56-057 
59 

717-718 

643-61+ 
644 
752 
725 

465-466 
712 
117 

105-118 

69-70 

478 

72-73 

138-139 

606 

G66 

11 

397 

392 

97 

35,67 

698,  700 
685 
657 

127-128 

166, 168 

723 

500 

627-628 

674 

617 

593 

11 

329,412 

333 

633 

634 

10 

633-634 

633-634 


714 
615 


R. 

Rabbit  fossils 42,124 

104 
13 

489 
782 
753 

11 
767 

73 
768 


IJaccoon  Creek,  detlectioD  by  glacial  bouiulary 

Kacine,  Wis.,  piolile  across  Lake  Micbipni  near 

Kue,  E.  C  and  Greenli-af,  J.  L.,  estimate  of  discliarge 

tlirough  Kock  River  Valley,  miule  by 

Kaleigb,  111.,  wells  at '. 

Ramsey.  III.,  wells  near 

Kanilolpli  County,  III.,  altitude  of 

yener.nl  features  of 

ridgo  in  Jackson  County  and 

tal)le  of  well  sections  in 


welts  iu 767-769 


INDEX. 


813 


Page. 

Rantoal,  111.,  wells  at 702 

Eavinia,  111.,  section  at 386 

well  at 581 

Kead,  W,  T.  B.,  referred  to 584 

EedBna.Ill.,w6ll3at 768 

Eentchler,  Dl.,  wells  at - 764 

Kicliardson,IU.,'"^ells  near 597 

Richland  County,  111.,  altitude  of 11 

general  features  of 756-757 

wells  in 756-757 

Kichland  Creek,  deflection  of,  by  glacial Tjoundary. . .  102-103 

drift  at 70 

Eidgway,  111.,  knolls  near 39 

wells  near 65,  783-784 

Eiggs,  E.  B.,  analyses  of  loess  by 164 

Eisk.m.,  wells  at 667 

Riverdale,  111 .,  well  at '. 590 

Eiver  Park.  111.,  well  near 588 

Riverside,  111.,  wells  at 589 

Robinson,  111.,  wells  at 755 

Rochelle,  111.,  wells  at 607-608 

Rock  Creek,  belt  of  loess  in 150 

Eockfalls,  m.,  wells  at 616-617 

Eock  floor,  table  of  altitudes  of 9-11 

Eockford,  HI.,  analyses  of  sand  near 16r^ 

gorge  near 492 

well  at 572 

Rock    gorges,    measurements    of,   in    northwestern 

Illinois 494 

Rock  Island,  111.,  analyses  of  loess  at 161 

exposures  of  silt  near 114 

section  of  well  at 114 

Eock  Island  County,  111.,  altitude  of 9 

general  features  of 619-620 

table  of  wells  in 620-621 

wells  in 619-621 

Eockport,  Ind  ,  loess  near 156 

Eock  Eiver,  course  of 485,  486^87 

descent  of  the  lower  portion  of 492 

drainage  basin  of 483-493 

excavation  along,  near  Pine  Creek 489 

gravel  plain  in  valley  of 490-491 

preglacial  valley  of 483-484 

rock  excavation  in  the  new  course  of 487 

table  of  well  sections  east  of,   in  "Winnebago 

County,  111 570-572 

time  of  deflection  of 491-492 

Rock  surface,  Michigan,  Indiana,  and  Iowa,  average 

altitude  of 12 

Rockville,  drift  near 200 

Rolfe,  C.T7.,  aidby 7 

cited  on  altitudes  in  Illinois 7,12 

maps  of  Chicago  Outlet  by,  mentioned 421 

records  of  wells  collected  by 223 

referred  to 375, 701 

sections  of  boring  reported  by 235,236 

Rome,  Iowa,  abandoned  channel  of  the  Mississippi 

River  near 90,  92,  93 

Roodhouse,  HI.,  wells  at 745 

Rosebud,  111.,  wells  near 78? 

EoseUe,  HI.,  wells  near 592 

Rossville,  111.,  bowlders  at 269 

wells  at 699 

Round  Grove,  111.,  exposure  of  till  at 140 

ridge  at 135 

section  of  well  at ]  39 


Page. 

Ruma,  HI.,  wells  near 768 

EushviUe,  111.,  wells  at 712 

Eussell,  I.  C,  cited  on  Leaf  Eiver  or  Adeline  esker.  77 

Rynear,  knolls  near 230 

S. 

Saginaw  lobe,  extent  of 

St.  Anne,  111.,  wells  at 

St.  Charles,  111.,  wells  near. . 

St.  Clair  County,  HI.,  altitude  of.. 


341 

654 

597 

11 

general  features  of 761-762 

wells  in 761-765 

St.  Francisville,  HI.,  wells  at 756 

St.  George,  111.,  wells  near 654 

St.  Jacobs,  111.,  wells  at 750 

St.  Johns,  111.,  borings  at 772-773 

St.  Joseph,  Mich.,  thickness  of  drift  at 13, 392 

well  at 400 

St.  Joseph  Eiver,  drainage  basin  of 540 

gravelly  plain  on 434-4?5 

moraine  near 342,  352-353 

structure  of  drift  along 399-400 

St.  Louis,  Mo.,  deposits  near 64, 71 

drift  border  near 35,  37,  39 

limestone  belt  near 14, 15 

St.  Louis  County,  Mo.,  glacial  deposits  in 64-65 

St.  Marie,  111.,  well  at 755 

St.  Mary's,  111.,  wells  at 656 

St.  Mary's,  Ind.,  drift  at 201 

silt  near 208 

Salem,  111.,  coal  boring  at 759 

Saline  County,  111.,  general  features  of. 781-782 

wells  i  n 78 1-782 

Saline  Eiver,  course  of , 527-528 

Salisbury,  E.  D.,  cited  on  drift  in  southeastern  Illinois 

and  southwestern  Indiana 109 

cited  on  glaciation  of  limestone  ridges 15 

cited  on  mineralogical  constitution  and  size  of 

lowan  loess 158-159 

cited  on  the  drift  border 37 

fossils  collected  by 168 

glacial  work  of 3 

reference  to 43, 160, 166, 543, 547,  714, 745 

Salisbury,  R.D.,  and  Chamberlin,  T.  C,  cited  on  the 

drift  border  in  southern  "Wisconsin 43-44 

Salt  Creek,  course  of 504 

gravel  pit  between  Lagrange  and 438 

old  bay  in  basin  of 431-432 

outwash  in  valley  of 211 

topography  near 345 

Sandoval,  111.,  wells  at 759 

Sand  wich.  111.,  wells  at 604 

Sandy  Creek,  watershed  of 513 

Sanford,  111.,  section  of  drift  at .'...  201 

Sangamon,  analyses  of  bowlder  clays  at 163 

width  of  the  Illinois  Valley  near 499 

Sangamon  County,  111.,  altitude  of 10 

general  features  of 724 

wells  in 724^725 

Sangamon  Eiver,  exposures  near  Mahomet,  on 21G 

drift  in  the  valley  of 214 

outwash  in  valley  of 210-211 

topography  near 227 

watershed  of 517-520 

San  Jose,  111.,  wells  at 089 

Saunemin,  111.,  wells  at 667 


814 


INDEX. 


Page. 

Savanna,  IlL,  fosaila  found  at 166, 168 

well  at 611 

Sawyer,  Mich.,  section  at 399 

well  at 439 

Sawyer  Station,  Mich,  thickness  of  drilt  at 392 

Saybrook,  Til.,  wells  at 695 

Schererville,  depth  of  sand  at 439 

Schernierville,  111.,  wells  near 587 

Scblemming;J.,  information  furnished  by 613 

Scotland,  Ind.,  till  at 69 

Scottville,  111.,  wells  at 743 

Scovell,  J.  T.,  on  striae  in  Wabash  Valley 87 

Schuyler  County,  HI.,  altitude  of 10 

general  features  of 71 1-712 

wells  in 711-712 

Scott  County,  111.,  altitude  of U 

general  features  of 721-722 

weUsin 721-722 

Scott  County,  Iowa,  exposures  in 46 

Senachwine  Creek,  watershed  of 513 

Seneca,  111.,  wells  at 638 

Shannon,  111.,  wells  near 613 

Shaw,  .J;imes,  cited  on  Leaf  Eiver  or  Adeline  esker. .  76 

cited  on  well  at  Princeton,  111 628 

information  furnished  by 612 

Shawnee  Township,  Ind.,  outwash  in 239 

Sliawneetowu,  111.,  boring  at 65-66 

wells  at 784 

Shelby  County,  111.,  altitude  of 10 

general  features  of 737-738 

wollftin 737-740 

Shelbyville,  111.,  silt  near 198-199 

wells  at 739 

Shelbyville  drift  sheet,  extent  of 192 

Shelbyville  moraine,  character  and  extent  of 192-  213 

character  of  the  outwash  from 208 

distribution  of 193-194 

range  in  altitude  of 194-195 

relief  of 194 

structure  and  thickness  of  the  drift  of 197-208 

table  of  striae  within  limit  of 412-414 

topography  of 395-197 

topography  of  the  inner-border  tract 213 

ShelbjTille  till  sheet,  thickness  of  the  inner-border 

tract 213 

Sheldon,  111.,  analyses  of  bowlder  clays  at 163 

wells  near 659-660 

Sherbuniville,  111.,  wells  at 654 

Shiloh  Hill,  111.,  wells  at 769 

Shimek,  B.,  cited  on  distribution,  of  fossils 165 

cited  on  Limnaia 172 

list  of  fossils  revised  by 168-169 

notes  on  fossils 171-176 

quoted  on  loess  foaails 175-176 

Shi rley,  111.,  wells  at 695 

Shoal  Creek,  watershed  of 524-525 

well  in  valley  of 751 

Shovotail  Slough,  111.,  wells  at 661 

Shufeldt,  George  A.,  jr.,  referred  to 584 

Sidney,  111.,  section  in  boring  at 2.36 

wells  at 702-703 

Siebenthal,  C.  E.,  cited    on    deflections   of    White 

River .".33 

cited  on  deflections  of  small  streams  by  glacial 

boundary 102-103 

cited  on  drift  in  Morgan  County 70 


Page. 

Siebenthal,  C,  E.,  cited  on  drift  in  Owen  County 70 

cited  on  the  glacial  boundary 36-37 

reference  to 38, 88, 104 

Silt,  buried,  at  Atlanta,  III 206 

at  Monticello,  III 220 

at  Muscatine,  Iowa 47 

at  Stratford,  III 138,606 

in  Adams  County,  111 61,  62 

in  Muscatine  County,  Iowa 40 

in  northwestern  Illinois 111-118 

in  Rock  Island  County,  III 621 

on  east  bluff  of  Mississippi  River 115 

near  Keokuk,  Iowa 94 

near  Mahomet,  111 237 

near  Washington,  111 32 

near  Yarmouth,  Iowa 51 

Silver  Creek,  watershed  of 525-526 

Silveria  formation 112-118 

Simpson.  C.  T.,  fossils  identified  by . .  115, 1G8, 169, 170-171,  451 

Skunk  River,  interglacial  course  of 122-123 

Sloat,  William,  well  section  of 51 

Smith,  F. ,  well  section  of 51 

Smithboro,  111. ,  coal  boring  at 751 

Snyder,  J.  F.,  fossils  collected  and  identified  by 171 

information  furnished  by 711 

quoted  on  section  at  Virginia,  HI 108 

Soil,  buried,  at  and  near  Coatsburg,  111 62, 109,  716 

at  and  near  Davenport,  Iowa 45, 128 

at  and  near  Keokuk,  Iowa 94,  95,  96 

at  Arlington  Heights 587 

at  Ash  Grove,  111 661 

at  Atlanta.  Ill 206,708 

at  Clayton,  111 660 

atDalton,  111 730 

at  Decatur,  111 204 

at  Elkhart,  111 709 

atGalva,Ill 130,624 

at  Iroquois.  Ill 659 

at  Kansas,  111 217 

at  Marengo,  111 293 

at  Muscatine,  Iowa 47 

at  Pana,  111 107 

at  Piano,  111 644 

at  Rockville,  111 200 

at  Roundgrove,  111 139 

at  St.  Charles,  111 597 

at  Salem.  Ill 759 

at  Shavetail  Slough 661 

atlJrbana,  111 235 

at  Virginia,  III 108,711 

at  Woodstock,  111 577 

between  Dudley  and  Kansas,  HI 733 

between  Oregon  and  Mount  Morris.  Ill 606 

depth  of.  in  Illinois 263-266 

elevation  where  it  occurs 29 

exposures  of,  near  Henton,  111 59 

in  Adams  County,  HI 61 

in  Alden,  111 576 

in  Bureau  County,  HI 264,627 

in  Champaign  County,  111 240.701 

in  Clark  County,  111 733 

iuCook  County,  111 583,586 

in  Dokulb  County,  III 264 

in  Donniiirk,  Iowa 55 

in  Dowitt  County,  111 705 

in  Ford  County,  111 664 


INDEX. 


815 


Soil,  buried,  in  Hancock  and  Adams  conntiea,  111 

in  Iroquois  County,  111 141. 

in  Kane  County,  111 263-264,301, 

in  Kankakee  County,  111 

in  Kendall  County,  111 

in  Lasalle  County,  111 264, 

in  Lee  Countj',  111 

in  Lee  County,  Iowa 

in  McLean  County,  111 265, 

in  Ogle  County,  111 

in  Parke  County,  Ind 

in  southeastern  Iowa 

in  Vermilion  County,  111 

in  "SVill  County,  111 

on  east  bluff  of  the  Mississippi  Eiver 

near  Baylis,  111 

near  Belvidere,  111 

near  Clinton,  111 

near  Crescent,  111 

near  Denmark,  Iowa 

near  Elgin  ,111 

near  Greenup,  HI 

near  Hamilton,  111 

near  Lily  Lake,  111 

near  Mabomet,  111 

near  Marshall,  111 

near  Milton,  111  

near  Mount  Carroll,  111 

near  Mount  Pulaski,  HI 

near  Newton,  111 

near  Tbawville.  Ill 

near  W  apella.  Ill 

near  Washington,  111 

near  West  Point,  Iowa 

Somonauk  Creek,  knolls  along 

Sorento,  111.,  wells  near 

South  Fork,  watershed  of 

South  Haven,  Mich.,  section  of  boring  in 

thickness  of  drift  at 

South  Kisbwaukee  Kiver,  sand  and  gravel  deposits 
on 

topography  near 

South  Riley,  111.,  wells  at 

Sparta,  HI.,  section  of  Pleistocene  beds  near 

wells  at 

Spaulding  Station, HI.,  well  near 

Spencer,  J.  W.,  cited  on  uplift  of  Niagara  outlet 

Spoon  Eiver,  watershed  of 

gravel  deposits  near  valley  of 

Springfield,  111.,  generalized  section  of  wells  north- 
west of 

wells  at 

Spring  Hill,  HI.,  exposures  near  

paha  near  . 

wells  near 

Spring  Lake,  depth  of 

Stark,  HI.,  wells  near 

dtark  County,  111.,  altitude  of 

general  features  of 

wells  in 

Staunton,  HI.,  wells  at 

Steeleville,  111.,  wells  at 

Stephenson  County,  111.,  altitude  Of 

area  of 

silt  deposit  in 

table  of  well  sections  in 


Page. 

105, 106 

265,  657 

597,  598 

325,  654 
645 

641,  642 

264 

40,52 

693,  696 
607 
200 

120-121 
698 
651 
U5 
720 
139 
205 
659 
54 

585, 596 
127 
57 
294 
216 
129 
720 
612 
709 
717 
661 

706-707 

32 

53,70 

287-288 
751 
519 
401 
392 

278 

246-247 

578 

117 

769 

585 

453 

516-517 

276-277 

125 
725 

133, 140 
135 
618 
441 
672 
10 
672 
672 

743-744 

769 

9 

567 

113 

568-569 


Stephenson  County,   HI.,  transported  rock  ledges 

near  Dakota 83 

wells  in 567-569 

Sterling,  HI. ,  wells  at 616-617 

Sterling,  Iowa,  glacial  deposits  near 146 

Stillman  Valley,  HI .,  wells  near 606 

Stillwell,  111.,  filled  valley  near 51 

Stilter,  William,  well  section  of 42 

Stockton,  wells  in  preglacial  valley  north  of 566 

Strata,  altitude  of,  in  Illinois 553-554 

Stratford,  exposure  of  fossiliferous  silt  at 138 

wells  at 606 

Strawn,  111. ,  wells  at 667 

Streator,  111.,  wells  at 639 

Strife,  glacial 84-88 

at  Burlington 85-86 

near  Hamilton  ,111 105 

outside  the  Shelbyville  moraine  (table) 88 

Stronghurst,  111.,  wells  at 680 

Structure  of  drift  border  in  southeastern  Iowa 40-43 

Sugar  Creek,  belt  of  gravel  on 272-273 

course  of 536 

gravel  terraces  in  valley  of 239 

watershed  of 519,  536 

Sugar  Grove  Township,  111.,  wells  in 599 

Sullivan,  IlL,  depth  of  drift  at 217 

wells  at 730 

Summerfieldjll.,  wells  at 763 

Summit,  111.,  wells  at 589 

Sumner,  HI.,  wells  near 756 

Swan  wick,  111.,  wells  at 771 

Sweet,  T,  0..  information  furnished  by 371 

Sweetwater,  111.,  wells  at 710 

Sycamore,  HI.,  wells  at 603 

Sykes,  J.,  well  section  of 60 

T. 

Taylor.  F.  B.,  ci  ted  on  the  beaches  of  Lake  Michigan .  420 

suggestion  by 356 

Taylorville,  lU .,  wells  near 726 

Tazewell  County,  111.,  altitude  of 10 

general  features  of 689-690 

thickness  of  drift  in 265 

wells  in 689-692 

Terre  Haute,  Ind.,  analyses  of  loess  near 164 

Texas  City,  III.,  wells  at 782 

Thawville,  111.,  wells  at 661 

Thebes.  111.,  deflection  of  the  Mississippi  River  at. . .  474 

well  at 786 

Thomasville,  111.,  wells  at 741 

Time,  HI.,  exposures  and  wells  at 63 

wells  at 721 

Timpe.  F.,  well  section  of 53 

Tippecanoe  River,  altitude  near 331-332 

sand  ridge  along 329 

Todd,  J.  E..  cited  on  drift  deposits 37 

cited  on  strite  at  Alton,  111 86 

Toledo,  111.,  wells  at 737 

ToUeston  beach,  altitude  of 452 

composition  of,  in  Illinois 450 

composition  of,  in  Indiana 450 

course  of 447-450 

Tolono,  drift  at 233 

Toluca,  111.,  wells  at 669 

Toronto  formation 20, 185, 189-190 

Totemeir,  Anton,  information  furnished  by 51 


816 


INDEX. 


Page. 

Touluo.Ill.,  weilaat 672 

Tower  Hill,  III.,  wells  at 739 

Townsliips,  method  of  numberiDg 4-6 

Trail  Creek,  drainage  basin  of 539 

old  bay  in  valley  of 432 

Troy,  111.,  wells  at 750 

Tme,  F.  W.,  cited  on  bones  found  in  peat 42 

examination  of  animal  remains  by 124 

Turkey  Creek,  ridge  along 387 

Turner  Junction,  111.,  wells  at 593 

Turner  Park,  111.,  wells  near 588 

Tuscola,  111.,  well  s  at  and  near 222, 731 

Tyrrell,  J.  P.,  cited  on  separation  of  Albertan  and 

sub-Aftonian  drift  sheets 21 

TJ. 

Udden.  J.  A.,  aid  by 114, 147, 148, 187 

analysis  of  loess  by 159 

cited  on  loess  deposition 177, 179 

cited  on  old   lake  bed  in   Muscatine  County, 

Iowa 96 

cited  on  the  rock  constituents  of  the  drifts  of 

Muscatine  County 44 

cited  on  wells  in  Rock  Island  County 621 

fossils  collected  by 115, 168, 1 70-171, 173-174 

information  furnished  by 412, 

616.  618,  620,  624,  625,  630,  634 
investigation  of   the  preglacial    course  of  the 

Mississippi 463,465,466 

trip  with 145-146 

well  record  obtained  by 615 

TJdden,  J.  A.,  Calvin,  Samuel,  and  Baiu,  H.Foster, 

w  ork  on  drifts 44-45 

Udden,  J.  A.,  and  ^McGee,  W  J,  cited  on  the  displace- 
ment of  the  Mississippi 90 

Underground  waters,  classification  of 550-55 

Unio  fossils 167 

Union  County.  HI.,  altitude  of 11 

Union  Grove,  111.,  wells  near 616 

Union  Hill,  111.,  wells  at 654 

Urbana,  111.,  section  of  boring  at 235 

wells  at 702 

Ustick,  111.,  wells  near 615 

Utica.ni.,  wellsat 638 

Valleys,  preglacial 17,18 

Valparaiso  morain ic  system,  altitude  of,  range  in . . .  343-344 

distribution  of 339-340 

drainage  of  the 379 

drift,  thickness  of 353-355 

eastern  border  of 340-341 

topography  of 345-348 

Van  lluren  County,  Mich.,  thickneaa  of  drift  in 355 

wells  ill 366,367,368,370,371,372 

Vandaha.  111.,  wells  near 752-753 

Vanderburg  County,  Ind.,  change  of  drainage  in  . . .  97 

drift  border  lu 35 

wells  in 67 

Van  Tnyl,  S.,  well  section  of 54 

Vclpen,  Inil.,  col  near 100 

Vermilion  County,  111.,  altitude  of 10 

drift  structure  in 267 

general  features  of 697-608 

till  idain  in 239-240 

wolla  in 697-700 


Page. 
Vermilion  Kiver,  course  and  watershed  of  the  "Wa- 
bash    53&-537 

Vermilion  River,  drift  structnre  along 283 

moraine  near 279 

sand  ridge  near 330 

topography  near 311 

watershed  of 511 

Vermilion  ville,  HI.,  well  at 6:19 

Vermont,  111.,  wells  at 68« 

Verona,  111.,  wells  at 647 

Versailles,  111.,  wells  at 713 

Vicksburg,  Miss.,  analysis  of  loess  at 164 

Vienna,  HI.,  wells  at 786 

Virden,  wells  at 743 

Virginia,  111.,  analysis  of  bluff  loess  at 160,161 

fossils  found  at 171 

section  at 108 

weUsat 127,711 

Wabash  County,  111.,  altitxide  of 11 

general  features  of 775 

wells  in 775-776 

"Wabash  River,  deflections  of 530 

drainage  basin  of 528-529 

gravel  terraces  in  valley  of 238 

knolls  east  of 228-229 

outwash  in  valley  of 208-209 

preglacial  valley  of 529-530 

strife  in  valley  of 87 

"Wallace,  S.  J.,  relerence  to 95 

"Wapella,  111.,  wells  at 215,706 

Warren,  G.  K.,  cited  on  preglacial  channel  of  the 

Mississippi  River 469 

"Warren,  altitude  of 566 

wells  near 566 

Warren  County,  III.,  altitude  of 10 

general  features  of 678 

'  wellsin 678-679 

Warrick  County,  Ind .,  changes  of  drainage  in 98 

Warsaw,  HI.,  analysis  of  soil  at 163 

exposures  at 94-95 

wells  at 683 

Washbrrns  Mound 299 

Washington,  111.,  section  of  a  cutting  near 32 

wells  at 690-691 

Washington  County,  111.,  altitude  of 11 

general  features  of 770 

wells  in 770 

Washington  Heights,  111.,  well  at 589 

Waleiliio,  111.,  wfUsat 766 

Waterloo  quartzite,  movement  of 110-111 

Water  supply,  sources  of,  for  towns  in  lUiuois 558-564 

Watseka,  HI.,  wells  at 659 

Wancond,  111.,  wells  near 580 

Waukegan,  111.,  beach  near 429 

wells  at 5811 

Waupecan  Creek,  watershed  of 508-501) 

Waverly.  HI.,  wells  at 724 

Wayne,  111.,  wells  near 592 

Wayne  County,  111.,  altitude  of U 

general  features  of 774 

wellsin 774-775 

Waynesville.  111.,  wells  at 706 

Wellington,  HI.,  wella  at 660 


INDEX. 


817 


Tagr. 

W^ls,  artesian,  conditions  for 555-556 

"SVenona,  111.,  weUs  at 669 

"West  Point,  Iowa,  exposure  of  Sangamon  soil  at 129 

sections  near 5:-J,  70 

West  Salem,  111.,  wells  near 776 

Wheaton,  111.,  wells  at --■  593 

"Wheeler,  H.  A.,  cited  on  drift  deposits 37 

Wheeler,  Ind.,  section  of  ridge  north  of 396 

"White,  C.  A.,  cited  on  animal  remains  at  Davenport, 

Iowa 127, 128 

cited  on  peat  bed  at  Davenport,  Iowa 128 

reference  to :-  88 

White  County,  111.,  altitude  ot H 

general  features  of 776-777 

wells  in 776-777 

"Whitehall,  111.,  wells  at 745 

"White  Lake,  depth  of *41 

"White  Eiver,  course  and  watershed  of 532-534 

pregliicial  and  present  course 10-1 

preglacial  valley  of 534 

"Whitney,  Milton,  aniilyses  of  loess  by 159, 160 

quoted  on  analyses  of  white  clay 796 

quoted  on  hluft'  loess 794 

quoted  on  howlder-clay  soils  of  Illinois 792 

quoted  on  soils 789-790 

"Whiteside  County,  111.,  altitude  of 11 

general  features  of 148,  614^615 

loess  deposit  in 154 

table  of  wells  in -         617 

wells  in 614-619 

"Will  County,  ni.,  altitude  of 10 

general  features  of :  -  -  648-649 

table  of  wells  on  Valparaiso  morainio  system  id.  650-651 
table  of  wells  outside  the  Valparaiso  raorainic 

system 652 

wells  in 648-652 

"Williams,  L.,  wells  drilled  by 49-50 

Willliamstield,  111,  wells  at 677 

"William-son  County,  111.,  altitude  of 11 

general  features  of 780-781 

"Wilmette,  lll.,wellat 587 

"Wilmington,  111.,  wells  at 650 

"Wilson,  James  H.,  report  upon  the  survey  of  the 

Illinois  Eiver  mentioned 418 

"Winchell,  Alexander,  cited  on  bowlders  in  Van  Buren 

County 358 

cited  on  deep  channels  along  east  shore  of  Lake 

Michigan  441 

"Winchester,  111.,  wells  near 722 

"Windsor,  111.,  wells  at 202,739 

"Wine  Hill,  111.,  wells  at 769 

"Winfleld,  Iowa,  abandoned  valley  near 90, 91,  92, 93 

"Winnebago  County,  altitude  of 9 

gravel  knolls  in 136 

situation  and  area  of 569-570 

table  of  well  sections  in 570-572 

till  ridges  in 135 

wells  in 569-573 


Page. 

Wmiietkrt,  Ill.,driltnear 385 

till  ridge  near 381-382 

well  at 587 

"Wisconsin,  altitude  of 7 

"Wisconsin  and  lowan  drift  sheets,  soil  and  peat  be- 
tween    185-186 

"Wisconsin  drift,  character  of 141-143 

beached  loess  beneath  the 187-188 

limits  of 262-263 

"Wisconsin  drift  sheets,  extent  of  early 191. 

Wisconsin,  structure  of  drift  border  in  southern  ....      43-44 

Witter,  F.  M.,  fossils  identified  by 168-169 

cited  on  mammalian  remains  in  loess 166,167 

cited  on  wells  in  Louisa  County,  Iowa 49 

"Woburn.ni.,  wells  at., 752 

Woodford  County,  111.,  altitude  of 10 

general  features  of .- 670 

wells  in 264,670-672 

Woodstock,  111.,  wells  at 577 

Woodworth,  J.  E.,  cited  on  !N"antucket  as  a  morainal 

island,  S.C.Curtis  and 272 

Woolridge,  C.  W.,  cited  on  the  deep  channels  along 

east  shore  of  Lake  Michigan 441 

Wooster,  L.  C,  geologic  work  of 3, 339 

Worth,  III.,  bowlders  near 426 

wells  at 690 

Worthen,  A.  H.,  cited  on  drift  deposits 37 

cited  on  drift  phenomena  of  northwestern  Illi- 
nois   76 

cited  on  changes  in  drift  structure  at  Clinton..  205 

cited  on  mammalian  remains  in  loess 166 

cited  on  Niagara  limestone  areas 16 

cited  on  section  at  Virginia,  111 108 

cited  on  section  of  well  at  Paua,  111 107 

cited  on  the  interval  of  degluciation 125 

reference  to 2,157,526,714,726 

AVright,  G.  F.,  cited  on  drift  deposits 37 

cited  on  strife  in  Williamson  and  Jackson  coun- 
ties, Illinois 87 

Wyoming,  111.,  analysis  of  soil  at 102 

wells  near 672 

X. 

Xenia,  111.,  wells  at 758 

Y. 

Yarmouth.  Iowa,  bones  found  in  peat  near 42 

sections  of  wells  near 42,51 

Yarmouth  soil  near  DenmarK,  Iowa 54 

Yates,  111.,  wells  at 677-678 

"Yellow  banks  "  section  near  Keokuk, Iowa 94 

Yellow  River,  watershed  of  the 507 

Yorkville,  111.,  wells  at 644 

Z. 

Zeeland  Ridge,  altitude  of 391 

course  of 390-391 


MON   XXXVIII- 


-52 


A.D  ^^  E  R  T I S  EM:E  INT  T. 

[Monograph  XXXVIII.] 


The  statute  approved  March  3,  1879,  establishing  the  United  States  Geological  Survey,  contains 
the  following  provisions : 

"The  publications  of  the  Geological  Survey  shall  consist  of  the  annual  report  of  operations,  geo- 
logical and  economic  maps  illustrating  the  resources  and  classification  of  the  lands,  and  reports  upon 
general  and  economic  geology  and  paleontology.  The  annual  report  of  operations  of  the  Geological 
Survey  shall  accompany  the  annual  report  of  the  Secretary  of  the  Interior.  All  special  memoirs  and 
reports  of  said  Survey  shall  be  issued  in  uniform  quarto  series  if  deemed  necessary  by  the  Director,  but 
othervf  iseiu  ordinary  octavos.  Three  thousand  copies  of  each  shall  be  published  for  scientific  exchanges 
and  for  sale  at  theprice  of  publication ;  and  all  literary  and  cartographic  materials  received  in  exchange 
shall  be  the  property  of  the  United  States  and  form  a  part  of  the  library  of  the  organization :  And  the 
money  resulting  from  the  sale  of  such  publications  shall  be  covered  into  the  Treasury  of  the  United 
States." 

Except  in  those  cases  in  which  an  extra  number  of  any  special  memoir  or  report  has  been  sup- 
plied to  the  Survey  by  special  resolution  of  Congress  or  has  been  ordered  by  the  Secretary  of  the 
Interior,  this  office  has  no  copies  for  gratuitous  distribution. 

ANNUAL  REPORTS. 

.  I.  First  Annual  Report  of  the  United  States  Geological  Survey,  by  Clarence  King.  1880.  8°.  79 
pp.     i  map. — A  preliminary  report  describing  plan  of  organization  and  publications. 

II.  Second  Annual  Report  of  the  United  States  Geological  Survey,  1880-81,  by  J.  W.  Powell. 

1882.  8°.     Iv,  588  pp.     62  pi.     1  map. 

III.  Third  Annual  Report  of  the  United  States  Geological  Survey,  1881-'82,  by  J.  W.  Powell. 

1883.  8°.     xviii,  564  pp.     67  pi.  and  maps. 

IV.  Fourth  Annual  Report  of  the  United  States  Geological  Survey,  1882-'83,  by  J.  W.  Powell. 

1884.  8°.     xxxii,  473  pp.     85  pi.  and  maps. 

V.  Fifth  Annual  Report  of  the  United   States   Geological  Survey,  1883-'84,  by  ,J.  W.  Powell. 

1885.  8"^.     xxxvi,  469  pp.     58  pi.  and  maps. 

VI.  Sixth  Annual  Report  of  the  United  States  Geological  Survey,  1884-85,  by  J.  W.  Powell. 
1885.     8°.     sxix,  570  pp.     65  pi.  and  maps. 

VII.  Seventh  Annual  Report  of  the  United  States  Geological  Survey,  1885-'86,  by  .J.  W.  Powell. 

1888.  8°.     XX,  656  pp.     71  pi.  and  maps. 

VIII.  Eighth  Annual  Report  of  the  United  .States  Geological  Survey,  1886-'87,  by  J.  W.  Powell. 

1889.  8°.     2  pt.     xix,  474,  xii  pp.,  53  pi.  and  maps;  Iprel.  leaf,  475-1063  pp.,  54-76  pi.  and  maps. 

IX.  Ninth  Annual  Report  of  the  United  States  Geological  Survey,  1887-'88,  by  J.  W.  Powell. 

1889.  8^.     xiii,  717  pp.     88  pi.  and  maps. 

X.  Tenth  Annual  Report  of  the  United  States  Geological   Survey,  1888-89,  by  J.  W.  Powell. 

1890.  8^.     2  pt.     XV,  774  pp.,  98  pi.  and  maps;  viii,  123  pp. 

XI.  Eleventh  Annual  Report  of  the  United  States  Geological  Survey,  1889-'90,  by  J.  W.  Powell. 

1891.  8".     2  pt.     XV,  757  pp.,  66  pi.  and  maps;  ix,  351  pp.,  30  pi.  and  maps. 

XII.  Twelfth  Annual  Report  of  the  United  States  Geological  Survey,  1890-'91,  by  J.  W.  Powell. 
1891.     8°.    2  pt.,  xiii,  675  pp.,  53  pi.  and  maps;  xviii,  576  pp.,  146  pi.  and  maps. 

■  XIII.  Thirteenth  Annual  Report  of  the  United  States  Geological  Survey,  1891-'92,  by  J.  W. 
Powell.  1893.  8°.  3  pt.  vii,  240  pp.,  2  maps;  x,  372  pp.,  105  pi.  and  maps;  xi,  486  pp.,  77  pi.  and 
maps. 

XIV.  Fourteenth  Annual  Report  of  the  United  States  Geological  Survey,  1892-'93,  by  J.  W. 
Powell.    1893.     8°.     2  pt.     vi,  321  pp.,  1  pi. ;  xx,  597  pp.,  74  pi.  and  maps. 

XV.  Fifteenth  Annual  Report  of  the  United  States  Geological  Survey,  1893-'94,  by  J.  W.  Powell. 
1895.     8°.     xiv,  755  pp.,  48  jil.  and  maps. 

XVI.  Sixteenth  Annual  Report  of  the  United  States  Geological  Survey,  1894-95,  Charles  D. 
Walcott,  Director.  1895.  (Part  I,  1896.)  8°.  4  pt.  xxii,  910  pp.,  117  pi.  and  maps;  xix,  598  pp.,  43 
pi.  and  maps;  xv,  646  pp.,  23  pi. ;  xix,  735  pp.,  6  pi. 

XVII.  Seventeenth  Annual  Report  of  the  United  States  Geological  Survey,  1895-'96,  Charles 
D.  Walcott,  Director.  1896.  »\  3  pt.  in  4  vol.  xxii,  1076  pp.,  67  pi.  and  maps;  xxv,  864  pp.,  113  pi. 
and  maps;  xxiii,  542  pp.,  8  pi.  and  maps;  iii,  .543-1058  pp.,  9-13  pi. 

XVIII.  Eighteenth  Annual  Report  of  the  United  States  Geological  Survey,  1896-'97,  Charles  D. 
Walcott,  Director.     1897.    (Parts  II  and  III,  1898.)     8°.    opt.  in  6  vol.     1-440  pp.,  4  pi.  and  maps;  i-v, 

I 


II  ADVERTISEMENT. 

1-653  pp.,  105  pi.  anil  maps;  i-v,  1-8H1  pp.,  US  pi.  and  iiia|is:   i-x,  1-7511  pp.,  102  dI.  .'inil   maps:  i-xii, 
1-1)12  pp.,  1  pi. ;  043-1100  pi>. 

XI.\.  Niuetnenth  Aii'ual  Report  of  the  United  .States  Geological  Snrvi-y,  18y7-"9S,  Cliarles  D. 
Walcott,  Directoi-.     1808.     8.     0  pt.  iu  7  vol. 

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X.  Dinocerata.  A  Monograph  of  .in  Extinct  Order  of  Gigantic  Mammals,  by  Othniel  Charles 
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XI.  Geological  History  of  Lake  Lahontaii,  a  yuaternary  Lake  of  Northwestern  Nevada,  by 
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XII.  Geology  and  Mining  Industry  of  Leadville,  Colorado,  with  Atlas,  by  Samuel  Franklin 
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XIV.  Fossil  Fishes  and  Fossil  Plants  of  the  Triassic  Rocks  of  New  Jersey  and  the  Connecticut 
Valley,  by  ,Iohn  S.  Newberry.     1888.     4-'.     xiv,  152  pp.     26  pi.     Price  $1.00. 

XV.  The  Potomac  or  Younger  Mesozoic  Flora,  by  William  Morris  Fontaine.  1889.  4'^.  xiv, 
377  pp.     180  pi.     Text  and  plates  bound  separately.     Price  $2.50. 

XVI.  The  Paleozoic  Pishes  of  North  America,  by  John  Strong  Newberry.  1889.  4°.  340  pp. 
53  pi.     Price  $1.00. 

XVII.  The  Flora  of  the  Dakota  Group,  a  Posthumous  Work,  by  Leo  Lesquereux.  Edited  by 
F.  H.  Knowltrtu.     1891.     4^\     400  i>p.     66  pi.     Price  $1.10. 

XVIII.  Gasteropoda  and  Cephalo])oda  of  the  Raritan  Clays  and  Greeusand  Marls  of  New  .Jersey, 
by  Robert  P.  Whitfield.     1891.     4-.     402  pp.     50  pi.     Price  $1.00. 

XIX.  The  Penokee  Iron-Bearing  Series  of  Northern  Wisconsin  and  Michigan,  by  Roland  D. 
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XX.  Geology  of  the  Eureka  District,  Nevada,  with  an  Atlas,  by  Arnold  Hague.  1892.  4".  xvii, 
419  pp.     8 1)1.     Price  $5.25. 

XXI.  The  Tertiarv  Rhynchophorous  Coleoptera  of  the  United  States,  by  Samuel  Hubbard  Scud- 
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XXII.  A  Manual  of  Topographic  Methods,  by  Henry  Gannett,  Chief  Topographer.  1893.  4°. 
xiv,  300  pp.     18  pi.    Price  $1.00. 

XXIII.  Geology  of  the  Green  Mountains  in  Massachusetts,  by  Raphael  Piimpelly,  T.  Nelson  Dale, 
andJ.E.  Wolff.     1894.     4^.     xiv,  206  pp.     23  pi.     Price  $1.30. 

XXIV.  Mollusca  and  Crustacea  of  the  Miocene  Formations  of  New  Jersey,  by  Robert  Parr  Whit- 
field.    1894.    4".     193  pp.     24  pi.     Price  90  cents. 

XXV.  The  Glacial  Lake  Agassiz,  by  Warren  Upham.    189.5.   4-.  xxiv,  658  pp.   38  pi.    Price  $1.70. 

XXVI.  Flora  of  the  Aniboy  Clays,  by  John  Strong  Newberry;  a  P.  sthumous  Work,  edited  by 
Arthur  Hollick.     1895.     4^.     260  pp.     58  pi.     Price  $1.00. 

XXVII.  Geology  of  the  Denver  Basin  in  Colorado,  by  Samuel  Frauklin  Emmons,  Whitman  Cross, 
and  George  Homans  Eldridge.     1896.     4^^.     556  pp.     31  pi.     Price  $1..50. 

XXVIII.  The  Manjuette  Iron-Bearing  District  of  Michigan,  with  Atlas,  by  C.  R.  Van  Hise  and 
W.  S.  Bayley,  including  a  Chapter  on  the  Republic  Trough,  by  H.  L.  Smyth.  1895.  4".  608  pp.  35 
pi.  and  atlas  of  39  sheets  folio.     Price  $5.75. 

XXIX.  Gecdogy  of  Old  Hampshire  County,  Massachusetts,  comprising  Franklin,  Hampshire,  and 
Hampden  Counties,  by  Benjamin  Kendall  Emerson.     1898.     4''.     xxi,  790  pp.     35  pi.     Price  $1.90. 

XXX.  Fossil  Medusa',  by  Charles  Doolittle  Walcott.     1898.    4^'.     ix,201pp.     47  pi.     Price  $1.50. 

XXXI.  (ieology  of  the  Aspen  Mining  District,  Colorado,  with  Atlas,  by  .Josiah  Edward  Spurr. 
1898.     4''.     XXXV,  260  pp.     43  pi.  and  atlas  of  30  sheets  folio.     Price  $3.60. 

XXXII.  (ieology  of  the  Yellowstone  National  Park,  Part  II,  Descriptive  Geology,  Petrography,  ' 
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T.  W.  Stanton,  and  F.  II.  Kiiowlton.     1899.     4\     xvii,  893  pp.     121  pi.     Price . 

XXXIII.  Gecdogy  of  the  Narragaiisett  Basin,  bv  N.  S.  Slialer,  .).  B  Woodwnrth,  and  August  F. 
Foerste.     1899.     4".     xx,  402  pp.     31  pi.     Price . ' 


ADVERTISEMENT.  Ill 

XXXIV.  The  rUnoinl  Grnvels  of  Jlaiiic  auil  their  Associated  Deposits,  by  George  H.  Stono.  1899. 
4^'.     xiii,  1.  9  pp      ."iJ  ji-.     i'li^o . 

XXXV.  i'he  Later  Extinct  Floras  of  North  America.  ])j  John  Strong  Newberry;  edited  bv 
Arthur  Hollick.     1898.     4^~.     xviii,  295  pp.     68  pi.     Price  $1.2.5. 

XXXVI.  The  Crystal  Falls  Iron-Bearing  District  of  Michigan,  by  J.  Morgan  Clements  and 
Henry  Lloyd  Smyth;  with  a  Chapter  on  the  Sturgeon  River  Tougue,  by  William  Shirley  Bayley,  and  an 
introduction  by  Charles  Richard  Van  Hise.    1899.     4°.     xxxvi,  512  pp.     53  pi.     Price . 

XXXVII.  Fossil  flora  of  the  Lower  Coal  Measures  of  Missouri,  by  David  White.  1899,  4-. 
xi,  167  pp.     73  pi.     Price . 

XXXVIII.  The  Illinois  Glaciiil  Lobe,  by  Frank  Leverett.  1899.  4^.  xxi,  817  pp.  24  pi. 
Price . 

Jnprcpaialion: 

— Flora  of  the  Laramie  and  Allied  Formations,  by  Frank  Hall  Fnowlton. 

BULLETINS. 

1.  On  Hypersthene-Andesite  anil  on  Triclinic  Pyroxene  in  Augitic  Rocks,  by  Whitman  Cross. 
with  a  Geological  Sketch  of  Buft'alo  Peaks,  Colorado,  by  S.  F.  Emnious.  1S83.  8^.  42  jip.  2  pi. 
Price  10  cents. 

2.  Gold  and  Silver  Cimversion  Tables,  giving  the  Coining  Vahies  of  Troy  Ounces  of  Fine  Metal, 
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3.  On  the  Fossil  Faunas  of  the  Upper  Devonian,  along  the  Meridian  of  76^'  30',  from  Tompkins 
County,  N.  Y.,  to  Bradford  County,  Pa.,  by  Henry  S.  Williams.     1884.     8'-.     36  pp.     Price  5  cents. 

4.  On  Mesozoic  Fossils,  by  Charles  A.  White.     1884.     8-.     36  pp.     9  pi.     Price  5  cents. 

5.  A  Dictionary  of  Altitudes  in  the  United  States,  compiled  by  Henry  Gannett.  1884.  8°.  325 
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6.  Elevations  in  the  Dominion  of  Canada,  by  J.  W.  Spencer.     1884.     8°.     43  pp.     Price  5  ceiits. 

7.  Mapoteea  Geologica  AmeTicana.  A  Catalogue  of  Geological  Maps  of  America  (North  and 
South),  1752-1881,  in  Geographic  and  Chronologic  Order,  bv  Jules'Mai-eou  and  John  Belknap  Marcon. 

1884.  8'-.     184  pp.     Price  10  cents. 

8.  On  Seeoudaiy  Enlargements  of  Mineral  Fragments  in  Certain  Rocks,  by  R.  D.  Irving  and 
C.  R.  A^an  Hise.     1884.     8-.     56  pp.      6  pi.     Price  10  cents. 

9.  A  Report  of  Work  <lone  in  the  Washingtim  Laboratory  during  the  Fiscal  Year  1883-'84.  F.  W. 
Clarke,  Chief  Chemist;  T.M.  Chatard,  Assistant  Chemist.      1884.      8^.      40  pp.      Price  5  cents. 

10.  On  the  Cambrian  Faunas  of  North  America.  Preliminarv  Studies,  by  Charles  Di  olittle 
Walcott.      1884.     8"^.      74  pp.      10  pi.      Price  5  cents. 

11.  On  the  Quaternary  and  Recent  Mollusca  of  the  Great  Basin;  with  Description  of  New 
Forms,  by  R.  Ellsworth  Call.  Introduced  by  a  Sketch  of  the  Quaternary  Lakes  of  the  Great  Basin, 
by  G.  K.  Gilbert.     1884.     8°.     66  pp.     6  pi.     Price  5  cents. 

12.  ACrystallographicStudy  of  the  Thiuolite  of  Lake  Lahontan,  by  Edward  S.Dana.  1884.  8". 
34  pp.     3  pi.     Priieocents. 

13.  Boundaries  of  the  United  States  and  of  the  Several  States  and  Territories,  with  a  Historical 
Sketch  of  the  Territorial  Changes,  by  Henry  Gannett.     1885.    8°.     135  pp.     Price  10  cents. 

14.  The  Electrical  and  Magnetic  Properties  of  the  Iron-Carburets,  by  Carl  Barns  and  Vincent 
Strouhal.     1885.     8°.    238  pp.     Price  15  cents^ 

15.  On  the  Mesozoic  and  Cenozoic  Paleontology  of  California,  by  Charles  A.  White.  1885.  8^. 
33  pp.     Price  5  cents. 

16.  On  theHigherDevonianFaunasofOntarioCounty,  New  York,  by  John  M.Clarke.  1885.  8^. 
86  pp.     3  pi.     Price  5  cents. 

17.  On  the  Development  of  Crystallization  in  the  Igneous  Rocks  of  Washoe,  Nevada,  with  Notes  on 
the  Geology  of  the  District,  by  Arnold  Hague  and  Joseph  P.  Iddings.    1885.    8°.    44  pp.     Price  5  cents. 

18.  On  Marine  Eocene,  Fresh-Water  Miocene,  and  other  Fossil  Mollusca  of  Western  North 
America,  by  Charles  A.  White.     1885.    8'^.     26  pp.     3  pi.     Price  5  cents. 

19.  Notes  on  the  Stratigraphy  of  California,  by  George  F.Becker.    1885.    8".    28  pp.    Price  5  cents. 

20.  Contributions  to  the  Mineralogv  of  the  Rockv  Mountains,  by  Whitman  Cross  and  W.  F.  Hille- 
brand.     1885.     8".     114  pp.     1  pi.     Price' 10  cents. 

21.  The  Lignites  of  the  Great  Sioux  Reservation;  a  Report  on  the  Region  between  the  Grand 
and  Morean  Rivers,  Dakota,  by  Bailey  Willis.     18f5.     8'^.     16  ])p.     5  pi.     Price  5  cents. 

22.  On  New  Cretaceous  Fossils  from  California,  by  Charles  A.  White.  1885.  8°.  25  pp.  5  pi. 
Price  5  cents. 

23.  Ob.servations  on  the  Junction  between  the  Eastern  Sandstone  and  the  Keweenaw  Series  on 
Keweenaw  Point,  Lake  Superior,  by  R.  D.  Irving  and  T.  C.  Chamberlin.  1885.  8*-".  124  pp.  17  pi. 
Price  15  cents. 

24.  Listof  Marine  Mollusca,  comprising  the  Quaternary  Fossils  andRecent  Forms  fromAmerieau 
Localities  between  Cape  Hatteras  and  Cape  Roque,  including  the  Bermudas,  by  William  Healey  Dall. 

1885.  8".     336  pp.     Price  25  cents. 

25.  The  Present  Technical  Condition  of  the  Steel  Ihdustry  of  the  United  States,  by  Phineas 
Barnes.     1885.     8^.     85  pp.     Price  10  cents. 

26.  Copper  .Smelting,  by  Henry  M.  Howe.     1885.     8'-.     107  pp.     Price  10  cents. 

27.  Report  of  Work  done  in  the  Division  of  Chemistry  and  Phvsies,mainlv  during  the  Fiscal  Year 
1884-'8o.     1886.     8^.     80  pp.     Price  10  cents. 

28.  The  Gabbros  and  Associated  Hornblende  Rocks  occurring  in  the  Neighborhood  of  Baltimore, 
Maryland,  by  George  Huntington  Williams.     1886.     8*^.     78  pp.     4  pi.    Price  10  cents. 


IV  '  ADVERTISEMENT. 

29.  On  the  Fresh- Water luvertebrates  of  the  North  Aiuerican  Jurassic,  byCh-irles  A.  AVhite.  1886. 
8^.     41  PI).      4  pi.     Price  5  cents. 

30.  Second  Coutribntiou  to  the  Studies  on  the  Cambrian  Faunas  of  North  America,  by  Charles 
Doolittle  Walcott.     1886.     8-^.     369  pp.      33  pi.     Price  2,5  cents. 

31.  Systematic  Review  of  our  Present  Knowledge  of  Fossil  Insects,  including  Myriapods  and 
Arachnids,  by  Samuel  Hubbard  Seudder.     1886.     8°.     128  pp.     Price  15  cents. 

32.  Lists  and  Analyses  of  the  Mineral  Springs  of  the  United  States;  a  Prelimiuarv  Study,  by 
Albert  C.  Peale.     1886.     8-\     23.5  pp.     Price  20  cents. 

33.  Notes  on  the  Geolo.iiy  of  Northern  California,  by  J.  S.Diller.     1886.    8°.    23  pp.     Price  5  cents. 

34.  On  the  Relation  of  the  Laramie  Molluscau  Fauna  to  that  of  the  Succeeding  Fresh-Water  Eocene 
and  Other  Groups,  by  Charles  A.  White.     1886.     8'-.     54  pp.     5  pi.     Price  10  cents. 

35.  Physical  Properties  of  the  Iron-Carburets,  by  Carl  Barus  and  Vincent  Strouhal.  1886.  8^. 
62  pp.     Price  10  cents. 

36.  Subsidenceof FineSolidParticlesiuLiquids,by CarlBarus.    1886.    8-.    58pp.    Price lOcents. 

37.  Types  of  the  Laramie  Flora,  by  Lester  F.  Ward.     1887.     8^.     354  pp.     57  pi.     Price  25  cents. 

38.  Peridotiteof  ElliottCouuty, Kentucky,  by  J.  S.  Diller.     1887.     8-^.    Sljip.     Ipl.    Price5cents. 

39.  The  Upper  Beaches  and  Deltas  of  the  Glacial  Lake  Agassiz,  by  Warren  Upham.  1887.  8-'. 
84  pp.     1  pi.     Price  10  cents. 

40.  Changes  in  Ri\er  Courses  in  Washington  Territory  due  to  Glaciation,  by  Bailey  Willis.  1887. 
8^.     10  pp.     4  pi.     Price  5  cents. 

41.  On  the  Fossil  Faunas  of  the  Upper  Devonian — the  Geivesee  Section,  New  York,  bv  Henry  .S. 
Williams.     1887.     8^.     121  pp.     4  pi.     Price  15  cents. 

42.  Reportof  Work  done  in  the  Division  of  Chemistry  and  Physics,  mainly  during  the  Fiscal  Year 
1885-'86.     F.W.  Clarke,  Chief  Chemist.     1887.     8-.     152  pp.     1  pi.'    Price  15  cents. 

43.  Tertiary  and  Cretaceous  Strata  of  the  Tuscaloosa,  Tombigbee.  and  Alabama  Rivers,  by  Eugene 
A.  Smith  and  Lawrence  C.  .Johnson.     1887.     8".     189  pp.     21  pi.     Price  15  cents. 

44.  Bibliography  of  North  American  Geology  lor  1886,  by  Nelson  H.  Darton.  1887.  8°.  35  pp. 
Price  5  cents. 

45.  The  Present  Condition  of  Knowledge  of  the  Geology  of  Texas,  by  Robert  T.  Hill.  1887.  8^. 
94  pp.     Price  10  cents. 

46.  Nature  and  Origin  of  Deposits  of  Phosphate  of  Lime,  by  R.  A.  F.  Penrose,  jr.,  with  an  Intro- 
duction by  N.  S.  Shnler.     1888.     8°.     143  pp.     Price  15  cents. 

47.  Analyses  of  Waters  of  the  Yellowstone  National  Park,  with  an  Account  of  the  Methods  of 
Analysis  employed,  by  Frank  .\ustin  Gooch  and  James  Edward  Whitfield.  1888.  8°.  84  pp.  Price 
10  cents. 

48.  On  the  Form  and  Position  of  the  Sea  Level,  by  Robert  Simpson  Woodward.  1888.  8*^.  88 
pp.     Price  10  cents. 

49.  Latitudes  and  Longitudes  of  Certain  Points  in  Missouri,  Kansas,  and  New  Mexico,  by  Robert 
Simpson  AVoodward.     1889.     8^^.     133  pp.     Price  15  cents. 

50.  Formulas  and  Tables  to  Facilitate  the  Construction  and  Use  of  Maps,  by  Robert  Simpson 
Woodward.     1889.     8*^.     124  pp.     Price  15  cents. 

51.  On  Invertebrate  Fossils  from  the  Pacific  Coast,  by  Charles  Abiathar  White.  1889.  8°.  102 
pp.     14  pi.     Price  15  cents. 

.52.  Subai-rial  Decay  of  Rocks  and  Origin  of  the  Red  Color  of  Certain  Formations,  by  Israel 
Cook  Russell.     1889.     8^.'    65  pp.     5  pi.     Price  10  cents. 

53.  The  Geology  of  Nantucket,  by  Nathaniel  Southgate  Shaler.  1889.  8^.  55  pp.  10  pi.  Price 
10  cents. 

54.  On  the  Thermo-Electric  Measurement  of  High  Temperatures,  l>y  Carl  Barus.  1889.  8°. 
313  pp.,  iucl.  1  pi.     11  pi.     Price  25  cents. 

55.  Rejiort  of  Work  done  in  the  Division  of  Chemistry  and  Physics,  mainly  during  the  Fiscal 
Year  1886-'87.     Frank  Wigglesworth  Clarke,  Chief  Chemist.     1889.     8".     96  pp.     Price  10  cents. 

56.  I'ossil  Wood  and  Lignite  of  the  Potomac  Formation,  by  Frank  Hall  Kuowlton.  1889.  8^. 
72  pp.     7  pi.     Price  10  cents. 

57.  A  Geological  Reoonnoissance  in  Southwesteru  Kansas,  by  Robert  Hay.     1890.     8"^.     49  pp. 
.  2  pi.     Price  5  lents. 

58.  The  Glacial  Boundary  in  Western  Pennsylvania,  Ohio,  Kentucky,  Indiana,  and  Illinois,  by 
George  Frederick  Wright,  with  an  Introduction  by  Thomas  Cbrowder  Chamberlin.  1890.  8-^.  112 
pp.,  incl.  1  pi.     8  pi.     Price  15  cents. 

59.  The  (ialibros  and  A.S80ciated  Rocks  in  Delaware,  by  Frederick  D.  Chester.  1890.  8".  45 
pp.     1  pi.     Price  10  cents. 

60.  Report  of  Work  done  in  the  Division  of  Chemistry  and  Physics,  mainly  during  the  Fiscal 
Year  1887-'88.     F.  \V.  Clarke,  Chief  Chemist.     1890.     8-.     174  i)p.     Price  15  cents. 

61.  Contributions  to  the  Mineralogy  of  the  Pacitic  Coast,  by  William  Harlow  Melville  and  Wal- 
demar  r>inilgren.     1890.     8°.     40  pp.     3  pi.     Price  5  cents. 

62.  The  Gn^enstone  Schist  .\reas  of  the  Menominee  .and  Marquette  Regions  of  Michigan,  a  Con- 
tribution to  the  Subject  of  Dyuaniic  Metamorphism  in  Eruptive  Rocks,  by  George  Huntington  Williams, 
with  an  Introduction  by  Roland  llucr  Irving.     1890.     8  .     241pp.     16  pi.     Price  30  cents. 

63.  A  Hibli(igra|)liy  of  Paleozoic  Crnstaci'a  from  1698  to  1889.  including  a  List  of  North  Amer- 
ican Species  and  a  Systcnuitic  .\rrangcment  of  (ieuera,  by  Anthony  \V.  Vogdes.  1890.  8*^.  177  pp. 
Pri<e  15  cents. 

64.  .V  Report  of  Work  done  in  the  Division  of  Chemistry  and  Plivsi<-s,  maiulv  during  the  Fiscal 
Year  18S8-'S9.     F.  \V.  Clarke,  Chief  Chemist.     1890.     8^^.     60  pp.     Price  10  cents.  ' 


ADVERTISEMENT.  V 

65.  Stratigraphy  of  tlie  Bituminous  Coal  Field  of  Penusvlvania,  Ohio,  and  West  Virginia,  by 
Israel  C.  White.     1891.     8°.     212  pp.     11  pi.     Price  20  cents. 

66.  On  a  Group  of  Volcanic  Rocks  from  the  Tewan  Mountains,  New  Mexico,  and  on  the  Occur- 
rence of  Primary  Quartz  in  Certain  Basalts,  by  Joseph  Paxson  Iddiugs.  1890.  8°.  34  pp.  Price  5 
cents. 

67.  The  Relations  of  the  Traps  of  the  Newark  System  in  the  New  Jersey  Region,  by  Nelson 
Horatio  Darton.     1890.     8°.     82  pp.     Price  10  cents. 

68.  Earthquakes  in  California  in  1889,  by  James  Edward  Keeler.  1890.  8^.  25  pp.  Price  5 
cents. 

69.  A  Classed  and  Annotated  Biography  of  Fossil  Insects,  by  Samuel  Howard  Scudder.  1890. 
8°.     101pp.     Price  15  cents. 

70.  A  Report  on  Astronomical  Work  of  1889  and  1890,  by  Robert  Simpson  Woodward.  1890.  8°. 
79  pp.     Price  10  cents. 

71.  Index  to  the  Known  Fossil  Insects  of  the  World,  including  Myriapods  and  Arachnids,  by 
Samuel  Hubbard  Scudder.     1891.     8°.     744  pp.     Price  50  cents. 

72.  Altitudes  between  Lake  Superior  and  the  Rocky  Mountains,  by  Warren  Upham.  1891.  8°. 
229  pp.     Price  20  cents. 

73.  The  Viscosity  of  Solids,  by  Carl  Earns.     1891.     8^.     xii,  139  pp.     6  pi.     Price  15  cents. 

74.  The  Minerals  of  North  Carolina,  by  Frederick  Augustus  Genth.     1891.     8°.     119  pp.     Price' 
15  cents. 

75.  Record  of  North  American  Geology  for  1887  to  1889,  inclusive,  by  Nelson  Horatio  Darton. 
1891.     8°.     173  pp.     Price  15  cents. 

76.  A  Dictionary  of  Altitudes  in  the  United  States  (Second  Edition),  compiled  by  Henry  Gannett, 
Chief  Topographer.     1891.     S''.     393  jip.     Price  25  cents. 

77.  The  Texan  Permian  and  its  Mesozoic  Types  of  Fossils,  by  Charles  A.  White.  1891.  8°.  51 
pji.     4  pi.     Price  10  cents. 

78.  A  Report  of  Work  done  in  the  Division  of  Chemistry  and  Physics,  mainly  during  the  Fiscal 
Year  1889-'90.     F.  W.  Clarke,  Chief  Chemist.     1891.     8".     131  pp.     Price  15  cents. 

79.  A  Late  A'olcanic  Eruption  in  Northern  California  and  its  Peculiar  Lava,  by  J.  S.  Diller. 

80.  Correlation  Papers — Devonian  and  Carboniferous,  by  Henry  Shaler  Williams.  1891.  8°. 
279  pp.     Price  20  cents. 

81.  Correlation  Papers — Cambrian,  by  Charles  Doolittle  Walcott.  1891.  8°.  .547  pp.  3  pi. 
Price  25  cents. 

82.  Correlation  Papers— Cretaceous,  by  Charles  A.  AVhite.  1891.  8*^.  273  pp.  3  pi.  Price  20 
cents. 

83.  Correlation  Papers— Eocene,  by  AVllllam  Bullock  Clark.  1891.  8°.  173  pp.  2  pi.  Price 
15  cents. 

84.  Correlation  Papers— Neocene,  by  W.  H.  Dall  and  6.  D.  Harris.  1892.  8^.  349  pp.  3  pi. 
Price  25  cents. 

85.  Correlation  Papers — The  Newark  System,  by  Israel  Cook  Russell.  1892.  8°.  344  pp.  13  pi. 
Price  25  cents. 

86.  Correlation  Papers — Archean  and  Algonkiau,  by  C.  R.  Van  Hise.  1892.  8^.  549  jip.  12  pi. 
Price  25  cents. 

87.  A  Synopsis  of  American  Fossil.  Brachiopoda,  including  Bibliographv  and  Synonymy,  by 
Charles  Schuchert.     1897.     8^.     464  pp.     Price  30  cents. 

88.  The  Cretaceous  Foraminifera  of  New  Jersey,  by  Rufus  Mather  Bagg,  Jr.  1898.  8<^'.  89  pp. 
6  pi.     Price  10  cents. 

89.  Some  Lava  Flows  of  the  Western  Slope  of  the  Sierra  Nevada,  California,  by  F.  Leslie 
Ransome.     1898.     8".     74  pp.     11  pi.     Price  15  cents. 

90.  A  Report  of  Work  done  in  the  Division  of  Chemistry  and  Physics,  mainly  during  the  Fiscal 
Year  1890--91.     F.  W.  Clarke,  Chief  Chemist.     1892.     8°.     77  pp.     Price  10  cents. 

91.  Record  of  North  American  Geology  for  1890,  by  Nelsou  Horatio  Darton.  1891.  8'^.  88  pp. 
Price  10  cents. 

92.  The  Compressibility  of  Liquids,  by  Carl  Barus.     1892.     8°.     96  pp.     29  pi.     Price  10  cents. 

93.  Some  Insects  of  Special  Interest  from  Florissant,  Colorado,  and  Other  Points  in  the  Tertiaries 
of  Colorado  and  Utah,  by  Samuel  Hubbard  Scudder.     1892.     8^.     35  pp.     3  pi.     Price  5  cents. 

94.  The  Mechanism  of  Solid  Viscosity,  by  Carl  Barus.     1892.     8^.     138  pp.     Price  15  cents. 

95.  Earthquakes  in  California  in  1890  and  1891,  by  Edward  Singleton  Holden.  1892.  8°.  31pp. 
Price  5  cents. 

96.  The  A^olume  Thermodynamics  of  Liquids,  by  Carl  Barus.     1892.     8'^.     100  pp.     Price  10  cents. 

97.  The  Mesozoic  Echiuodermata  of  the  United  States,  by  W.B.Clark.  1893.  8°.  207  pp.  50pl. 
Price  20  cents. 

98.  Flora  of  the  Outlying  Carboniferous  Basins  of  Southwestern  Missouri  bv  David  White. 
1893.     8^.     139  pp.     5  pi.  •  Price  15  cents. 

99.  Record  of  North  American  Geology  for  1891,  by  Nelson  Horatio  Darton.  1892.  8°.  73  pp. 
Price  10  cents. 

100.  Bibliography  and  Index  of  the  Publications  of  the  U.  S.  Geological  Survey,  1879-1892,  by 
Philip  Crevellng  Warman.     1893.     8°.     495  pp.     Price  25  cents. 

101.  Insect  Fauna  of  the  Rhode  Island  Coal  Field,  liy  Samuel  Hubbard  Scudder.  1893.  8°. 
27  pp.     2  pi.     Price  5  cents. 

102.  A  Catalogue  and  Bibliograpliy  of  North  American  Mesozoic  Invertebrata,  by  Cornelius 
Breckiuridgo  Bnyle.     1892.     8'^.     315  pp.     Price  25  cents. 


VI  ADA^ERTISEMENT. 

103.  High  Teraper;>tur(>  Work  in  I^iifoiis  I'lisicm  ami  Klnillition,  lUidly  in  Reliiti"ii  to  Pi-pssiire, 
ly  Carl  Ii.trns.     ]sn".     S\     57  pp.     9  pi.     I'licc  I.)  cuiits. 

104.  Gluciation  of  tbe  YeUowstone  Valley  iiortli  of  the  Park,  liy  Walter  Harvey  Weed.  18H3.  8^. 
41  pp.     4  pi.     Price  5  cents. 

105.  The' Laramie  aud  the  Overlyiiin-  Liirin^jstone  Forinatiou  in  Montana,  hy  Walter  Harvey 
AVeeil,  with  Report  on  Flora,  l)y  Frank  Hal!  Knowltoii.     1.S93.     8-.     68  pp.     6  ])1.     Price  10  cent.s. 

106.  The  t'olorado  Formation  and  its  Invertebrate  Fanna.  liy  'J'.  W.  Stanton.  1893.  8-.  i?88 
pp.     45  pi.     Price  20  cents. 

107.  Tlie  Traji  Dikes  of  the  Lake  Chamidain  Rcsjion,  by  .lames  Fiirman  Kemp  aud  Vennm 
Freeman  JIarsters.     1S93.     8-.     62  pp.     4  pi.     Price  10  cents. 

108.  A  Geological  Recounoissance  in  Central  Washington,  by  Israel  Cook  Russell.  1893.  8-. 
108  pp.     12  pi.     Price  15  cents. 

109.  The  Eruptive  and  Sedimentary  Rocks  on  Pigeon  Point,  Minnesota,  and  their  Contact  Phe- 
nomena, by  William  Shirley  Bayley.     1893.     8-^.     121pp.     16  pi.     Price  15  cents. 

110.  The  Paleozoic  Section  in  the  Viciuitv  of  Three  Forks,  M(mtaua,  bv  Albert  Charles  Peale. 
893.     8".     56  pp.     6  pi.     Price  10  cents. 

111.  (Jenlogy  of  the  Big  Stone  Gap  Coal  Fields  of  Virginia  aud  Keutuckv,  bv  ilarins  R.  Camp- 
bell.    18!";.     8.''lC6]ip.     6'pl.     Price  15  cents. 

112.  Earthquakes  in  California  in  1892,  by  Charles  D.  Perrine.    1893.    8-^.    57  pp.    Price  10  cents. 

113.  A  Report  of  Work  done  iu  the  Division  of  Cheniistrv  during  the  Fiscal  Years  1891-'92  and 
1892-'93.     F.  W.  Clarke,  Chief  Chemi.'it.     189.3.     8-'.     115  pp.     Price  15  cents. 

114.  Earthquakes  iu  California  iu  1893.  by  Charles  D.  Perrine.     1894.    8-.    1^3  jiu.    Price  5  cents. 

115.  A  Geographic  Dictionary  of  Rhode  Island,  by  Henry  Gaunett.  1894.  8-.  31pp.  Price 
5  cents. 

116.  A  Geographic  Dictionary  of  Massachusetts,  by  Henry  (Januett.  1894.  8-.  126  pp.  Price 
15  cents. 

117.  A  Geographic  Dictionary  of  Counecticut,  by  Henry  Gannett.  1894.  8-^.  67  pp.  Price  10 
cents. 

118.  A  Geographic  Dictionary  of  New  .Jersey,  by  Henry  Gannett.  1894.  8^.  131  pp.  Prii'c  lo 
cents. 

119.  A  Geological  Recounoissance  iu  Xorthwest  Wyoming,  by  George  Homans  Kldridge.  1894. 
8°.      72  pp.     Price  lo  cents. 

120.  The  Devonian  System  of  Eastern  Pennyslvania  ami  New  York,  by  Charles  .S  Prosser.  1894. 
8-.     81pp.     2  pi.     Price  10  cents. 

121.  A  Bil>liography  of  North  American  Paleontology,  by  Charles  Rollin  Keyes.  1894.  8-.  251 
pp.      Price  20  cents. 

122.  Results  of  Primary  Triangnlatiou,  by  Henry  Gaunett.  1894.  8^.  412  pp.  17  pi.  Price 
25  cents. 

123.  A  Dictionary  of  Geographic  Positions,  by  Henry  Gannett.  1895.  8-.  183  pji.  1  ]il.  Price 
15  cents. 

124.  Revision  of  North  American  Fossil  Cockroaches,  by  Samuel  Ilubbnrd  Scudder.  1895.  8^. 
176  pj).     12  pi.     I'rice  15  cents. 

125.  The  Constitution  of  the  Silicates,  by  Frank  AViggleswortb  Clarke.  1895.  8-=.  109  pp. 
Price  15  cents. 

126.  A  Mineralogical  Lexicon  of  Franklin,  Hampshire,  and  Hampden  counties.  Massachusetts, 
by  Beuiamin  Keudall  Emerson.     1895.     8^.     180  pp.     1  pi.     Price  15  cents. 

127.  Catalogue  and  Index  of  Contributions  to  North  .-Vmericau  Geologv,  1732-1891,  bv  Nelson 
Horatio  Dartou.     1896.     8-.     1045  pp.     Price  60  cents. 

128.  Tiie  Bear  River  Formation  and  its  Characteristic  Fauna,  by  Charles  A.  White.  1895.  8-^. 
108  pp.     11  pi.     Price  15  cents. 

129.  Earthquakes  iu  California  in  1894,  by  Charles  D.  Perrine.    1895.     8-^.     25  pp.     Price  5  cents. 

130.  Bibliography  and  Index  of  Nortli  American  Geology,  Paleoutologv,  Petrology,  and  Miner- 
alogy for  1892  and  1893,  by  Freil  I'.onghton  Weeks.     1896.     8.     210  pp.     Price  20  ceuts.' 

131.  Report  of  I'rogress  of  the  Division  of  Hydrography  for  the  Calendar  Years  1893  aud  1894, 
by  Frederick  Hayuea  Newell,  Topographer  in  Charge.     1895.     8^.     126  pp.     Price  15  cents. 

132.  The  Disseminated  Lead  Ores  of  Sontheastern  Jlissouri,  by  Arthur  Wiuslow.  1896.  S''. 
31  pp.     Price  5  cents. 

1.33.  Contributions  to  the  Cretaceous  Paleontology  of  the  Pacific  Coast:  The  Fauna  of  the 
Knoxville  Beds,  by  T.W.  Stanton.     1895.     8^.     132  pp.     20  pi.     Price  15  cents. 

131.  'i'he  Cambrian  Rocks  of  Pennsylvania,  by  Charles  Doolittle  Walcott.  1896.  8*^.  43  pp. 
15  pi.     Price  5  cents. 

135.  Bibliography  and  Index  of  North  American  Gecdog.y,  Paleontology,  Petrology,  and  Miner- 
alogy for  the  Year  1894,  by  F.  B.  Weeks.     1896.     8'='.     141  pp.     Price  15  cents. 

136.  \'olcaiiic  Rocks  of  South  Mountain,  Pennsylvania,  by  Florence  Bilscom.  1896.  S'-"..  121  ]i]i. 
28  pi.     Price  15  ( i-nts. 

137.  The  (ieologv  of  the  Fort  Riley  Military  Reservation  and  Vicinity.  Kansas,  bv  Robert  Hay. 
1896.     8^.     35  ]ip.     8  pi.     Price  5  cents. 

138.  Artesiau-Well  Prospects  iu  the  Atlantic  Coastal  Plain  Region,  by  N.  H.  Dartou.  1896.  8~' 
22X  pj).     19  id.      Price  20  cents. 

139.  Geology  of  the  Castle  Mountain  Mining  District,  Montaua,  by  W.  H.  Weed  and  L.  V.  Pirs- 
son.     1896.     8-.     lfit]ip.     17  pi.     Price  15  cents. 

140.  Ri'port  of  Progress  of  the  Divisiim  of  Hydrography  fur  the  Calendar  Year  1895,  by  Frederick 
Ilavncs  >'e'.>"i  11,  :  !ydnigr:nilicr  in  Cliar.'e.     l.S9i;.     H  .     iTi'l  n:'.     Pi  i'e  25  ceuts. 


ADVERTISEMENT.  VII 

"141.     The  Eocene  Deposits  of  the  Middle  Atlantic  Slope  in  DeliUTare,  Maryland,  and  Virginia, 
Ijy  William  Bullock  Clark.     isy6.     8-.     167  pp.     40  pi.     Price  15  cents. 

142.  A  Brief  Contribution  to  the  Geology  and  Paleontology  of  Xorthwestern  Louisiana,  liv 
T.  Wayland  Vaughan.     18i^6.     8^'.    C.>  jip.     4  pi.     Price  10  cents. 

143.  A  Bibliography  of  Clays  and  the  Ceramic  Ai'ts,  by  .John  C.  Branner.  1896.  8^'.  114  pp. 
Price  15  cents. 

144.  The  Moraines  of  the  Missouri  Coteau  and  their  Attendant  Deposits,  by  .James  Edward  Todd. 
1896.     8^.     71pp.     21  pi.     Price  10  cents. 

145.  The  Potomac  Formation  in  A'irginia,  by  W.  M.  Fontaine.  1896.  S'-'.  149  pp.  2  pi.  Price 
15  cents. 

146.  Bibliography  and  Index  of  North  American  Geology,  Paleontology,  Petrologr,  and  Miner- 
alogy for  the  Year  1895,  by  F.  B.  Weeks.     1896.     S-.     130  ]ip.  'Price  15  cents'. 

147.  Earthquakes  in  California  in  1895,  by  Charles  D.  Perrine,x\ssistant  Astronomer  iu  Ch.arge 
of  Earthquake  Observations  at  the  Lick  Observatory.     1896.     8'-.     23  pp.     Price  5  cents. 

148.  Analyses  of  Rocks,  with  a  Chapter  on  Analvtical  Methods,  Laboratory  of  the  United  States 
Geological  Survey,  1880  to  1896,  by  F.  "\V.  Clarke  and  W.  F.  Hillebrand.  1897".  8^\  306  pp.  Price 
:lV  ceuxs. 

149.  Bibliography  and  Index  of  North  American  Geology,  Paleontology,  Petrology,  and  Miner- 
alogy for  the  Ye.'ir  1!S96,  by  Fri-d  Bough  ton  Weeks.     1897.     8°.     152  pp.     Price  15  cents. 

1.50.  Tlie  Educational  Series  of  Rock  Specimens  collected  and  distributed  by  the  United  States 
Geological  Survey,  by  .'osepli  Silas  Diller.     1898.     8"^.     398  pp.     47  pi.     Price  25  cents. 

151.  The  Lo\v<-r  Cretaceous  Gryphieas  of  the  Texas  Region,  by  R.  T.  Hill  and  T.  Wayland 
Vaughan.     1898.     8-.     139  pp.     25  pi.     Price  15  cents. 

152.  A  Catalogue  of  the  Cretaceous  and  Tertiary  Plants  of  North  America,  by  F.  H.  Kuowlton. 
1898.     8=.     247  Tip.     Price  20  cents. 

153.  A  Bibliographic  Index  of  North  American  Carboniferous  Invertebrates,  by  Stuart  Weller. 
1898.     8^^.     6.53  pp.     Price  35  cents. 

154.  A  Gazetteer  of  Kansas,  by  Henry  Gannett.     1898.     8"^.     246  pp.     6  pi.     Price  20  cents. 

155.  Earthquakes  in  California  in  1896  and  1897,  by  Charles  D.  Perrine,  Assistant  Astronomer 
in  Charge  of  Earthquake  Observations  at  the  Lick  Observatory.     189>',     8-.     47  pp.     Price  5  cents. 

156.  Bibliogra|ihy  a'nd  Index  of  North  American  Geology,  Paleontology,  Petrology,  and  Miner- 
alogy for  the  Year  1897,  by  Fred  Houghton  Weeks.     1898.     8"-.     130  pp.     j-'rice  15  cents. 

160.  A  Dictionary  of  Altitudes  in  the  United  States  (Third  Edition),  compiled  by -Henry 
Gannett.     1899.     8-.     775  pp.     Price  40  cent?. 

161.  Earthquakes  in  California  in  1898,  by  Charles  D.  Perrine,  Assistant  Astronomer  in  Charge 
of  Earthquake  Observations  at  the  Lick  Observatorj-.     1899.     8°.     31pp.     1  pi.     Price  5  cents. 

Jn  2)repuraiioii: 

157.  The  Gneisses,  Gabbro-Schists,  and  Associated  Rocks  of  Southeastern  Minnesota,  by  C.  W. 
Hall. 

158.  The  Moraines  of  southeastern  South  Dakota  and  their  Atteu<lant  Deposits,  by  ,1,  E.  Todd. 

159.  The  Geologj'  of  Eastern  Berkshire  County,  Massach\isetts,  by  B.  K.  Emerson. 

WATER-SUPPLY  AND  IRRIGATION  PAPERS. 

By  act  of  Congress  approved  June  11,  1896,  the  following  provision  was  made: 
"Provided,  That  hereafter  the  reports  of  the  Geolo  ical  Survey  in  relation  to  the  gauging  oi 
streams  and  to  the  methods  of  utilizing  the  water  resources  maybe  priu  ed  in  octavo  form"  not  to 
exceed  one  hundred  pa  es  in  length  and  live  thousand  copies  in  number;  one  thousand  copies  of  which 
shall  be  for  the  oHicial  us,  of  the  Geological  Survey,  one  thousand  ti\'e  hundred  copies  shall  be  deliv- 
ered to  the  Senate,  and  two  thousand  five  hundred  copies  .shall  be  delivered  to  the  House  of  Repre- 
sentatives, for  distribution." 

Under  this  law  the  following  papers  have  been  issued: 

1.  Pumping  Water  for  Irrigation,  by  Herbert  M.  '    ilson.     1896.     8^.     57  pp.     9  pi. 

2.  Irrigation  near  Phcenix,  Arizona,  by  Arthur  P.  Davis.     1897.     8^.     97  pji.     31  pi. 

3.  Sewage  Irrigation,  by  George  W,  Rafter,     1897.     8".     100  pp.     4  pi. 

4.  AReconnoissance  in  southeastern  Washington,  by  Israel  Cook  Russell.    1897.    8°.    96  pp.    7  pi. 

5.  Irrigation  Practice  on  I  he  Great  Plains,  by  Elias' Branson  Cowgill.     1897.     8'^.     39  pp.     12  pi. 

6.  Underground  Waters  of  Southwestern  Kansas,  by  Erasmus  Haworth.    1897.    8'-.    65  pp.    12  pi. 

7.  Seepage  Waters  of  Northern  Utah,  by  Samuel  Fortier.     1897.     8"^.     50  pp.     3  pi. 

8.  Windmills  for  Irrigation,  by  Edward  Charles  Murphy.     1897.     8^^.     49  pp.     8  ill. 

9.  Irrigation  near  Greeley,  Colorado,  by  David  Boyd.     1897.     8*^.     90  pp.    21  pi. 

10.  Irrigation  in  Mesilla  Valley,  New  Mexico,  by  F.  C.  Barker.     1898.  8-\     51  jip.     11  pi. 

11.  River  Heights  for  1896,  by'Arthur  P.  Davis.'    i897.     8^\     100  pp. 

12.  AVater  Resources  of  Southeastern  Nebraska,  by  Nelson  H.  Darton.  1898.     8-.     55  pp.     21  pi. 

13.  Irrigation  Systems  in  Texas,  l)y  William  Ferguson  Hutson.     1898.  8^.     G7  pji.     10  pi. 

14.-  New  Tests  of  Certain  Pumps  and  Water-Lifts  used  in  Irrigation,  by  Ozni  P.  Hood.    1889.     8°. 
91  pp.     1  pi. 

15.  Operations  at  River  Stations,  1897,  Part  I.     1898.     8'^.     100  pp. 

16.  Operations  at  River  Stations,  1897,  Part  II.     1898.     8°.     101-200  pp. 

17.  Irrigation  near  BakersKeld,  California,  by  C.  E.  Grunsky.     1898^    8-.     96  pp.     16  pi. 

18.  Irrigation  near  Fresno,  California,  by  C.  E.  Grunsky.     1898.     8°.     94  pp.     14  pi. 

19.  Irrigation  near  Merced,  California,  by  C.  E.  Grunsky.     1899.     8-.     59  pp.     11  pi. 

20.  Experiments  with  Windmills,  by  T.  O.  Perry.     1899.'     8-.     97  pp.     12  pi. 


VIII 


ADVERTISEMKNT. 


21.  Wells  of  Northern  Indiana,  by  Frank  Leverett.      1899.     8^.     82  pp.     2  pi. 

22.  Sewage  Irrigation,  Part  II,  by  George  W.  Kalter.     1899.     8-.     100  pp.     7  pi. 

23.  Water-Right  Problems  of  Bighorn  Mountains,  by  Elwood  Mead.     1899.     8^.     62  pp.     7  pi. 

24.  Water  Resources  of  the  State  of  New  York,  Part  I,  by  George  W.  Rafter.  1899.  8°. 
99  pp.     13  pi. 

25.  Water  Resources  of  the  State  of  New  York,  Part  II,  by  George  W.  Rafter.  1899.  8-^. 
101-200  pp.     12  pi. 

26.  Wells  of  Southern  Indiana  (Continuation  of  No.  21),  by  Frank  Leverett.     1899.     8^.     64  pp. 

27.  Operations  at  River  Stations,  1898,  Part  I.     1899.     8°.     100  pp. 

28.  Operations  at  River  Stations,  1898,  Part  11.     1899.     8-.     101-200  pp. 

In  pre2>aration: 

29.  Wells  and  Windmills  in  Nebraska,  by  Edwin  H.  Barbour. 

30.  Water  Resources  of  the  Lower  Peninsula  of  Michigan,  by  Alfred  C.  Lane. 

TOPOGRAPHIC  MAP  OF  THE  UNITED  STATES. 

AVhen,  in  1882,  the  Geological  Survey  was  directed  by  law  to  make  a  geologic  map  of  the  United 
States  there  was  in  existence  no  suitable  topographic  map  to  serve  as  a  base  for  the  geologic  map. 
The  preparation  of  such  a  topographic  map  was  therefore  immediately  beguu.  About  one-fifth  of  the 
area  of  the  country,  excluding  Alaska,  has  now  been  thus  mapped.  The  map  is  published  in  atlas 
sheets,  each  sheet'  representing  a  small  quadrangular  district,  as  explained  under  the  next  head- 
ing. The  separate  sheets  are  sold  at  5  cents  each  when  fewer  than  100  copies  are  purchased,  but  when 
they  are  ordered  in  lots  of  100  or  more  copies,  whether  of  the  same  sheet  or  of  different  sheets,  the 
price  is  2  cents  each.  The  mapped  areas  are  widely  scattered,  nearly  every  State  being  represeuted. 
About  900  sheets  have  been  engraved  and  printed;  they  are  tabulated  by  States  in  the  Survey's 
•'List  of  Publications,"  a  pamphlet  which  may  be  had  on  application. 

The  map  sheets  represent  a  great  variety  of  topographic  features,  and  with  the  aid  of  descriptive 
text  they  can  be  used  to  illustrate  topographic  forms.  This  has  led  to  the  projection  ot  an  educational 
series  of  topographic  folios,  for  use  wherever  geography  is  taught  in  high  schools,  academies,  and 
colleges.     Of  this  series  the  first  folio  has  been  issued,  viz : 

1.  Physiographic  types,  by  Henry  Gannett,  1898,  folio,  consisting  of  the  following  sheets  and  4 
pages  of  descriptive  text:  Fargo(N.  Dak.-Minn.),  a  region  in  youth  ;  Charleston  (W.Va.),a  region  in 
maturity;  Caldwell  (Kans.),  aregion  in  old  age;  Palmyra  (Va.),  a  rejuvenated  region;  Mount  Shasta, 
(Cal.),  a  young  volcanic  mountain;  Eagle  (Wis.),  moraines;  Sun  Prairie  (Wis.),  drumlins;  Douald- 
sonville  (La.),  river  flood  plaius;  Boothbay  (Me.),  a  fiord  coast;  Atlantic  City  (N.  J.),  a  barrier-beach 

GEOLOGIC  ATLAS  OF  THE  UNITED  STATES. 

The  Geologic  Atlas  of  the  United  States  is  the  final  form  of  publication  of  the  topographic  and 
geologic  maps.  The  atlas  is  issued  in  parts,  progressively  as  the  surveys  are  extended,  and  is  designed 
ultimately  to  cover  the  entire  country. 

Under  the  plan  adopted  the  entire  area  of  the  country  is  divided  into  small  rectangular  districts 
(designated  qnadrangUs),  bounded  by  certain  meridians  and  parallels.  The  unit  of  survey  is  also  the 
unit  of  publication,  and  the  maps  and  descriptions  of  each  rectangular  district  are  issued  as  a  folio  of 
the  Geologic  Atlas. 

Each  folio  contains  topographic,  geologic,  economic,  and  structural  maps,  together  with  te.xtual 
descriptions  and  explanations,  and  is  designated  by  the  name  of  a  principal  town  or  of  a  prominent 
natural  feature  within  tlie  di.strict. 

Two  forms  of  issue  have  been  adopted,  a  "library  edition"  and  a  "field  edition."  In  both  the 
sheets  are  bound  between  heavy  paper  covers,  but  the  library  copies  are  jiermanently  bound,  while 
the  sheets  and  covers  of  the  field  copies  are  only  temporarily  wired  together. 

Under  tiie  law  a  copy  of  each  folio  is  sent  to  certain  public  liiiraries  and  educational  institu- 
tions. The  vciuainder  are  sold  at  25  cents  oacli,  except  such  as  contain  an  nuusual  amount  of  matter, 
which  are  priced  accordingly.  Prepayment  is  obligatory.  The  folios  ready  for  distribution  are  listed 
below. 


No. 


Nunie  of  shoot. 


State. 


Livingston Montana.. 

_,.  ,,  fdi'orgia-.- 

lt"'i'i!0''l ClViim-ssec 

Vlacorville 

Kingston 

Sacramento 

Clialtanooga 

I'ikes  Pcalt  (outot'stoclt). 

Sewanee 

AnHiracitc-Crcstcd  Butte 


Harpers  yerrj- . 


C'alil'oriiia. . 
Tennessci;  . 
California. . 
Tfancsseo  . 

Colorado 

Tennessee . 
Colorado. 


Limiting  meridians. 


(Virginia 
West  Virginii 
l^Iarylaud 


1100-111° 
850-85°  30' 

120°  30'-121° 
81°  31l'-85o 

1210-121°  30' 
85°-85°  30' 

1050-1050  30' 

85°  30'-8C° 

106°  45'-107o  13' 

770  30'-78° 


Limiting  parallels. 


45°-16o 
340  30'-3So 

38°  30'-30O 
33°  30' -360 
38°  30'-39' 
35°-35°  30' 
38°  30'-39° 
35°-350  30' 
38°  45'-390 

390-30°  30' 


Area,  in 

Price, 

sq  iiaro 

in 

miles. 

cents. 

3,354 

25 

980 

25 

932 

25 

969 

23 

932 

25 

975 

25 

932 

25 

975 

25 

465 

50 

925 

25 

ADVERTISEMENT. 


IX 


No. 


29 


30 


Name  of  sheet. 


Jackson  . . 
Estillville  . 


Fredericksburg. 

Staunton 

Lassen  Peak 

KnoxTille , 


Marysville.. 
Smartsville . 

Stevenson  . . 


Cleveland 

Pikeville 

McMiuDville. 

Nomini 

Three  Forks . 
Loudon 

Pocahontas . . . 

Morriatown... 

Piedmont 


Nevada  City. 


[Nevada  City .  ] 
<  Grass  Valley. } 
(Banner  Hill  .J 

fGallatin  . . 
Na-  ICiinyon-. . 

[Shoshone. 

[Lake 


/Tellowstone 
\    tional  Park. 

Pyramid  Teak . 

Franklin 

Briceville 

Buckhannon 

Gadsden 

Pueblo 

Downieville 

Butte  Special 

Truckee 

"Wartbnrg 

Sonora 

Nueces 

Bidwell  Bar 

Tazewell 

Boise 

Kichmond 

London 

Tenmile  District  Special. 
Roseburg 

Holyoke 


California. 

{Virginia  .. 
Kentucky. 
Tennessee 
f  Maryland . 
\Virginia  . . 
^Virginia .. 
(West  Virginia.. 

California 

J  Tennessee 

INorth  Carolina 

California 

California 

{Alabama 
Georgia 
Tennessee 

Tennessee 

Tennessee 

Tennessee 

/Maryland 

\Virginia 

Montana 

Tennessee 

(Virginia 

\West  Virginia . 
Tennessee 

{Virginia ... 
Maryland 
West  Virginia.. 

California  . 


Limiting  meridians. 


"Wyoming  . 


California 

/Virginia 

IWest  Virginia . 

Tennessee 

West  Virginia  . 

Alabama 

Colorado 

California 

Montana 

California 

Tennessee 

California 

Texas 

California 

/Virginia 

\West  Virginia.. 

Idaho 

Kentucky 

Kentucky 

Colorado 

Oregon  

/Massachusetts  . 
IConnecticut 


121°  00' 
121°  01' 
20°  57' 


(12 
12: 
(]2I 


120°  30'-121° 
82"  30'-8a° 
770.770  30' 

790-790  30' 

121°-1220 

83°  30'-84° 

121°  30'-122o 
121°-121o  30' 

35°  30'-86° 

84°  30'-85° 
85°-85as30' 
85°  30'-86° 

76°  30'-77° 

111°-112° 
84°-81°  30' 

810-81°  30' 

830-83°  30' 

790-790  30' 

25"-1210  03'  45" 
35"-121°  05'  04" 
05"-121o  00'  25" 


120°-120°  30' 

790-790  30' 

84°-84o  30' 

80°-80o  30' 

860-86°  30' 

104°  30'-105o 

120°  30'-121° 

30"-112°  36'  42" 

1200-120°  30' 

84°  30'-85o 

120°-120°  30' 

100°-100o  30' 

121°-121°  30' 

81°  30'-82° 

116°-1160  30' 

840-810  30' 

840-840  30' 

IO60  8'-106o  16' 

I230-I230  30' 

720  30'-73o 


Limiting  parallels. 


38°-38°  30' 
36°  30'-37° 

38''-38°  30' 

380-38°  30' 

40O-41O 

35°  30'-36° 

390-39°  30' 
390-390  30' 

340  30'-35° 

350-350  30' 
350  30'-36o 
350  30'-36o 

380-38°  30' 

45°-46° 
350  30'-36o 
370-370  30' 
360-360  30' 


390  13'  50"-39°  17'  16" 
39°  10'  22"-39°  13'  60" 
39°  13'  50"-39°  17'  16" 


450  59'  28' 


38°  30'-39° 
38°  30'-39o 

360-36°  30' 
380  30'-39° 
34°-340  30' 
380-380  30' 
390  SO'^Oo 
'-46°  02'  54," 
390-390  30' 
360-360  30' 
370  30'-38o 
29°  30'-30° 
39°  30'-40° 

370-370  30' 
430  30'^4o 
370  30'-38° 
37°-37°  30' 
-39°  30'  30" 
43°-430  30' 

420-42°  30' 


Area,  in 
square 
miles. 


933 
957 

938 

938 

3,634 

925 

925 
925 


975 
969 
969 


3,354 
969 

951 

963 


11.65 
12.09 
11.65 


932 

963 
932 
980 
938 
919 

22.80 
925 
963 
944 

1,035 
918 

950 

■  864 

944 

950 

55 

871 


Price, 

in 
cents. 


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STATISTICAL  PAPERS. 

MineralKesourcesof  the  United  States  [1882],  by  Albert  Williams,  jr.  1883.     8°.     xvii,813pp. 

i  riC6  OU  C611XS. 

,n, .    Mineral  Resources  of  the  United  States,  1883  and  1884,  by  Albert  Williams,  jr.     1885.     8°      siv 

101b  pp.     Price  60  cents.                                                                         '  ' 

IMC     MmeralResources  of  the  United  States,  1885.     Division  of  Mining  Statistics  and  Technology. 

1886.     8°.     VII,  o76pp.     Price  40  cents.  °'' 

Mineral  Resources  of  the  United  States,  1886,  by  David  T.  Day.     1887.  8°.     viii,  813  pp      Price 

60  cents.  '         ■^■■ 

Mineral  Resources  of  the  United  States,  1887,  by  David  T.  Day.     1888.  8°.     vii,  832  pp.     Price 

Mineral  Resources  of  the  United  States,  1888,  by  David  T.  Day.     1890.  8°.     vii,  652  vv      Price 

50  cents.  ?         1 1 

MiueralResourcesof  the  United  States,  1889  and  1890,  by  David  T.Day.  1892      8°      viii  671  nn 

Price  oO  cents.                                                                                           "  '           '         '^'^' 

Mineral  Resources  of  the  United  States,  1891,  by  David  T.  Day.     1893.  8°.     vii.  630  pp.    Price 

0\}  cents.  ' 


X  •  ADVERTISEMENT. 

Mineral  Resonrres  <if  tliu  riiite.l  States,  18tl2,  liy  l):i\  ill  T.  Pay.  ISnS.  .«!-.  vii,8.50pp.  Price 
50  cents. 

Mineral  Re-sonrces  of  the  United  States,  1893,  by  David  T.  Day.  1»94.  H  .  viii,  810  pp.  Price 
50  cents. 

On  March  2, 1895,  the  following  provision  was  Included  in  an  act  of  Congress: 

"I'l-ovided,  That  hereafter  the  report  of  the  mineral  resource.s  of  the  United  States  sh:ill  he 
issned  as  a  part  of  the  report  of  the  Director  of  the  Geological  Survey." 

In  compliance  with  this  legislation  the  following  reports  Ijavc  been  published: 

Mineral  Resources  of  the  United  States,  1894,  David  T.  Day,  Chief  of  Division.  1895.  8- .  xv, 
646  pp..  2;i  pi. ;  xix,  7:i."i  pp.,  6  pi.     Being  Parts  III  and  IV  of  the  Sixteentli  Annual  Report. 

Mineral  Resources  of  the  United  States,  1895,  David  T.  Day,  Chief  of  Division.  1896.  8  . 
xxiii,  512  pp.,  8  pi.  and  maps;  iii,  .543-1058  pp.,  9-13  pi.  Being  Part  III  (in  2  vols.)  of  the  Seventeenth 
Annual  Report. 

Mineral  Resources  of  the  United  St;ites,  1896.  David  T.  Day,  Chief  of  Division.  1897.  8  . 
xii,  642  pp.,  1  pi. :  643-1400  pp.     Being  Part  V  (in  2  vols.)  of  the  Niueteentli  Annual  Rep(ut. 

Mineral  Resources  of  the  United  States,  1.^97,  David  T.  Day,  Chief  of  Division.  1898.  8-. 
viii,  651  pp.,  11  pi. ;  viii,  706  pp.     Being  Part  VI  (in  2  vols.)  of  the  Nineteenth  Annual  Report. 

The  money  received  from  the  sfle  of  the  .Survey  ]>ublications  is  deposited  in  the  Treasury,  and 
the  Secretary  of  that  Department  declines  to  receive  bank  checks,  drafts,  or  postage  stamps ;  all  remit- 
tances, therefore,  nuist  be  by  money  order,  made  payable  to  the  Director  of  the  United  .States 
Geological  Survey,  or  in  currency — the  exact  amount.  Correspondence  relating  to  the  publications 
of  the  Survey  should  be  addresseil  to 

The  DiREciiii:. 

Uniteh  States  Geological  Scrvey, 
Washington,  1).  C,  June,  1S99.  "Washington,  D.  C. 


[Take  tliis  leaf  out  and  paste  the  separated  titles  upon  three  of  your  cata- 
logue cards.  TLe  lirst  and  second  titles  need  no  addition  ;  over  the  third  "write 
that  subject  under  which  you  would  place,  the  book  in  your  library.] 


LIBRARY  CATALOGUE  SLIPS. 

TJmted  States.     Vepartment  of  ilie  interior.     (  U.  S.  geological  survey,} 
Deiiartment  of  the  interior  |  —  |  Monographs  |  of  the  |  United 
States  geological  survey  |  Volume  XXXVIII  |  [Seal  of  the  depart- 
ment] I 
Washington  |  government  printing  office  |  1899 
Second    title:   United    States   geologiiJal   snrvej'   |   Charles   D. 
Walcott,  director   |  —  |   The   |   Illinois   glacial  lobe   |   hy  |  Frank 
Leverett  |  [Vignette]  | 

Washington  |  government  printing  olBce  |  1899 
4°.    ixi,  817  pp.    24  pi. 


Leverett  (Frank). 

United  States  geological  survey  |  Charles  T>.  Walcott,  di- 
rector I  —  I  The  I  Illinois  glacial  lohe  |  by  |  Frank  Leverett  | 
[Vignette]  | 

Washington  |  government  printing  office  |  1899 

4°.     xxl,  817  pp.    24  pi. 

[United  States.    DeparUnent  of   the  interior.     {U.   S.  geological  survey.} 
Monograph  SXXVIII.] 


United   States   geological    survey   |    Charles   D.   Walcott,   di- 
rector I  —  I  The  I   Illinois  glacial  lobe   |  by   |   Frank  Leverett   | 
[Vignette]  | 

Washington  |  government  printing  office  |  1899 

4°.     xxi,  817  pp.     24  pi. 

[United  States.    Departrnent  of  the  interior.     ( Vf.   S.  geological  survey.) 
Monograph  XXXVIII.] 


